Thursday, September 30, 2021

Sign Of Season: Lake Effect Showers - Then More Unsettled Weather

It's that time of year, as sunshine becomes more rare in
Vermont this time of year: Gray skies, a fading garden and
tree leaves turning color this morning in St. Albans, Vermont.
 It was kind of rainy overnight and early this morning in much of the Champlain Valley of Vermont.

Everyone in Vermont is a bit damp, but the rain focused along the shores of Lake Champlain. The reason: Lake effect showers. 

That's a sure sign of the season.  That rain formed exactly the way lake effect snows develop in the winter. 

There's a rather moist air flow from the north to begin with. That air then flows over the lake. 

 The lake water is warmer than the air, so it's able to add more moisture to the air - think steam rising from your morning cup of hot coffee in your chilly kitchen. 

What is essentially that steam from the lake adds more moisture to the air. The wind then has to rise up over the land and the hills east of Lake Champlain.  The wetness in that rising air gets wrung out as showers. 

This kind of thing can't happen in summer because to get these showers, the water has to be warmer than the air above, not vice versa.  Had this been winter, places from Burlington south into northwestern Rutland County would have gotten a couple inches of snow.

Speaking of which, I don't think the mountain tops of Vermont got any snow last night.  Forecasts indicated it would get possibly cold enough for that to happen. As of early this morning, it was 37 degrees atop Mount Mansfield.  That's cold enough for perhaps a few wet snowflakes, but I haven't see any observations saying that happened.

 I do see that over in New Hampshire, taller Mount Washington was down to 28 degrees with rime ice forming.

Going forward, the weather is going to remain in that term I hate - unsettled.  That word feels so wishy-washy. It implies boring, with no real certainty as to what will happen out there.

Unfortunately, that's the situation we're in.  The weather pattern is stuck, with that upper low just to our northeast pinwheeling little disturbances through here.  So there's always a chance of a shower, but you never know when.

Any showers that do hit don't look like they'll amount to much over the next couple of days.

On top of that, another storm from the southwest will take a run at us over the weekend and early next week, but it's unclear how much progress it will make toward us because of the gummed up weather pattern. 

It will probably be able to spread some showers our way Sunday or Monday but will eventually get pushed back southward by that pinwheeling, stalled upper level low to our northeast, and a high pressure system over Canada.

This all makes forecasting the weather over the next several days rather iffy, or if you want to use that word, unsettled.

Wednesday, September 29, 2021

Crunch Time In Western Drought: A Permanent Drought Could Become A Permanent National Crisis

"Bathtub Ring" in Lake Mead behind Hoover Dam shows how
low the water is, and how high it should be. If this keeps up
for a few more years, we have a national crisis.
 Here in Vermont, the drought we were enduring this spring and early summer is nearly gone. Northern areas still need quite a bit of rain, but at least it's better.  

Not much rain is in the forecast, but there is hope that autumn storms will come along and wet us down further. Our drought in northern Vermont is not the biggest possible crisis.  

Out west, meanwhile, the situation is turning more dire.  You might have heard about those wonderful monsoon thunderstorms that created some flash floods in the Southwest this summer.  That might have led some people to believe the drought is ending out there, too.

Not a chance.  The summer thunderstorms lessened, but did not eliminate the drought in a few sections of Arizona.  But most of the heavy rain consisted of local downpours that swept down mountain slopes and canyons but didn't create any widespread wetting.  The storms were a drop in the bucket. 

Extreme drought lives on.  The only hope for relief comes this winter.  Normally, large storms crank through the West over the colder months, causing widespread rain and mountain snow.  They'll need many, many such storms this winter to ease this long lasting drought.  One wet winter will not be nearly enough to solve the problem. You'll need a string of them. 

For what it's worth, long range seasonal outlooks from NOAA paint a grim picture in the Southwest. They call for persistent dry weather all winter out there. Worse, the forecasts call for above normal temperatures, which increase evaporation and can make droughts even more dire.

Granted, long range forecasts months in advance can easily be inaccurate, but the early thinking is bad.

Until now, real people have not been super affected by this southwestern drought, but that's changing. 

When Lake Mead, behind Hoover Dam, is totally full, the water is 1,225 feet deep. Now, it's down to 1,075 feet or even a little lower than that.  That means conservation orders are in effect in parts of Arizona and farmers are now starting to have to let fields go fallow for lack of irrigation.

That's bad enough. But if this slow-motion disaster goes on for a few more years, it turns into a national crisis.

The drought that is making Lakes Mead and Powell so low was not just a one or two year affair, like the relatively minor drought we've had in Vermont.

The western drought has been building for a decade or more Climate change might well have permanently made the West hotter and drier than it once was.  So the winter rains could very well continue to fail indefinitely.

Experts are saying that climate change is making the weather more extreme. You might get a brief super wet period in which torrential rains hit the West, causing some serious flooding and briefly interrupting the slow decline of western reservoirs. 

But if climate scientists are right, we'll have to stop wondering if the explosive population growth over the past several decades in the Southwest was really such a good idea.

According to the Arizona Republic, there's a 41 percent chance Lake Mead water will be so low by 2025 that big cities like Phoenix could see sharply curtailed water supplies. And, if current projections hold, there's a one in five chance that by 2025, Hoover Dam, which holds back Lake Mead, will have to stop producing hydropower.

If that happens, electricity for 1.3 million people gets cut off.  Upstream Lake Powell might have to shut off the electric turbines due to low water by 2023.  There goes another source of electricity for 1.5 million people. 

The shortages of water and electricity at the very least could make life more difficult for millions of people. Some might become "climate refugees,"  leaving the Southwest for wetter, more hospitable parts of the United States.

This is a sign that the crap is hitting the fan with climate change. You can imagine the social and political upheaval if western drought causes large scale population shifts and migrations. This would affect us all, so the western drought is not just "their problem."

Remember, one study I wrote about recently suggested Vermont is one of the so-called "safer" places as climate change takes hold.  Will we get an influx of climate refugees?

Sure, with labor shortages and and aging population, a small surge of young, industrious people to the Green Mountain State would probably be a good thing overall.  But what if we see thousands upon thousands of people moving here at once?

This won't happen immediately, of course. It'll be a generational thing.  But great minds will have to plan for both what to do to confront the likely permanent drought in the Southwest. And they''ll have to figure out what to do about the widespread societal impacts that the drought and other effects of disastrous climate change might bring. 

We are obviously an already deeply divided nation.  We've divvied ourselves into mutually hostile tribes. That's not a recipe for cooperation.

We failed as a nation handling the pandemic, as we resorted to political hackery and profiteering, with deadly results. So what are the chances we'll get our act together and figure out as one nation how to confront the societal effects of climate change? Societal effects that might make the pandemic seem like a blip on the radar?

I'm not optimistic.

Tuesday, September 28, 2021

Not THAT Cool; Lagging Northern Hemisphere Autumn Keeps Vermont Chilly Spell Manageable.

When you get a partly cloudy, cool spell of 
weather in the fall, which is anticipated over 
the next week or so, shadows and sunlight
make the foliage look that much better.
 The long-anticipated cool air has arrived in Vermont for an extended spell.  

The chill won't be breaking any records, but it will be the coldest weather since early May, so it is a shock to the system.  

The chilliest weather looks like it will arrive tomorrow and Thursday, and there's still a chance of snow flurries on the mountain summits. 

In the grand scheme of things, this cool spell really isn't all that chilly, at least by historical standards.  It's been a LOT worse this time of year.  As always, I have the receipts to prove it.  

The Burlington area banana belt has seen snow flurries as early as September 20 in 1956 and 1991. On October 3-5, 1965 temperatures stayed in the 30s continuously for two and half days. There are many more examples. So you see how awful it can be. 

This cool spell will be a piece of cake compared to all that.  A long lasting piece of cake, but a piece of cake nonetheless.

Vermont's Champlain Valley, at least,  will most likely continue a long growing season. The last time Burlington reached 32 degrees was on April 27, and it's unlikely it will get that cold around there during this spell.

Interior sections of Vermont outside the Champlain Valley had frost in late May, and stand to see the chance of scattered frost during this cool spell if we get any clear, calm nights. Again, that's nothing unusual for this time of year.

The coolness is happening because an immense ridge of high pressure is poking all the way from the central United States northward into the high Arctic.  Here in Vermont, we're on the east side of that ridge, so some of the air we're getting is from the Arctic, just east of where the center of the ridge is poking northward.  

It isn't that cold around here, because up in the Arctic, that ridge of high pressure is making it very warm by the standards of the Arctic. Since the source of our cool air isn't that cold, our weather isn't particularly icy, either.

Most of the chill Wednesday and Thursday will be because we'll be directly under an upper level low pressure system.  It has its own independent pool of cold air several thousand feet above us, which will help reinforce the chill down here on the ground.

Plus, since the temperature will fall very rapidly they higher you go due to that cold pool above us, that will make the air unstable, generate lots of clouds to block the sun's warmth, and create some light, but cold showers.

Those showers will act to bring some of the cold air down to the surface.  Temperatures might actually fall into the 40s in some northern areas during Wednesday afternoon.  

This overall weather pattern will persist, so it won't warm up dramatically after the rest of this week and the weekend.   At least that upper level low will move to our northeast a bit, so we won't be under the coldest air. 

However the wind from the warmish northern Quebec will continue, so our temperatures will remain slightly below normal through early next week. But not bad! Highs will poke up into the low 60s, which is great for fall foliage viewing. But not cold. By the way, with this cool air, fall foliage will rapidly progress in Vermont over the next week.  

This weekend should bring us some spectacular autumn colors, especially in the Northeast Kingdom and high elevations of northern and central Vermont. 

Little disturbances, I'd guess you'd call them mini cold fronts will rotate around that upper low to our northeast through the weekend, which will generate some clouds each day through the weekend, with some sprinkles here and there.

Frankly, I like that mix of clouds and sun with the foliage.  It can create some dramatic shadows and shafts of sunlight that enhance the autumn landscape. 

It's hard for this type of weather pattern to break down, so it might not be until the middle of next week until we see a substantial change in the weather. 

Monday, September 27, 2021

Out Of State To Experience The Last Summer Day Of 2021

View from my airplane window the other day as we descended
into Sioux Falls, Vermont last Thursday.  It's awfully hot
out here on the Great Plains for late September! 
 I've got another couple of days out here in Yankton, South Dakota, and as I watch Vermont slowly plunge into its first real autumnal cool spell, it's full on summer out here.  

It was 92 degrees out here in Yankton Sunday, so it was a truly summer day. It wasn't very humid, so the heat was manageable. Forecasts call for temperatures of near 90 degrees in Yankton today and tomorrow.

This all will make my impending return to Vermont feel even chillier than it will be. And it will be chilly enough, as many Vermont towns will stay below 60 degrees Wednesday and Thursday. 

Normal temperatures out here in Yankton are only a little warmer this time of year than in Vermont. But extremes are wider. Daily record highs are hotter than in Vermont, and daily record lows are lower.

The bottom line is, if you think Vermont weather bounces around a lot, try the Northern Plains. 

Back in Vermont, I'm pretty sure there won't be any true summer weather again until next, well, summer. Or maybe late spring.  That hot air in the Plains is not heading toward Vermont. Instead, an upper level low pressure system will direct Canadian air over us for the next few days.

It's a dry pattern, too, which is too bad because northern areas of Vermont still need the rain. A cold front and weather disturbance today will produce a tenth to three tenths of an inch of rain today, which is really not a whole lot. 

Very light, scattered showers could roam around Wednesday and Thursday in the chilly air but won't amount to much.

So far at least, frost during this cool spell looks like it will be limited to the normal cold spots. But keep watching the forecast daily. If any part of Vermont ends up getting several overnight hours of clear skies and light winds during this cool spell, frost could be more widespread.

Sure, there will be warm days ahead as we're still early in autumn.  But sustained summer weather is gone until next year. 

Sunday, September 26, 2021

Yes, The "S" Word Was Mentioned, But Don't Panic. But Chilly! Also, Sam Update

OK, it won't look anything remotely like this anywhere in 
Vermont this upcoming week, but there's a chance of the
season's first flurries on some Green Mountain summits.
 For the first time this autumn, the National Weather Service in South Burlington has mentioned the "S" word. Yeah, snow.  

Before you go into a tizzy, it wasn't as if they were forecasting a major blizzard that would annihilate Vermont.

Instead, in their Saturday evening forecast discussion, meteorologist at the NWS office speculated whether it would get cold enough on the tippy top of some of the Green Mountain peaks on Wednesday to support snow flurries.  

The answer is maybe, but doubtful.

This is to say, however, that we are going to have our first true spell to of autumn chill.  It is pretty amazing to me that we've gotten all the way through September 25 and the "coldest" day so far this month had a high of 68 degrees.

By now, we should have had a couple or even few days that failed to crack 60 degrees.  You won't have to wait much longer for such chill, as such days are coming this week.

The forecast is trending colder.   A huge blocking pattern is setting up in which the middle of the nation is expected to bake under unseasonable heat.  (I'm still out visiting relatives in Yankton, South Dakota today and the forecast high temperature here in Yankton today is a really, really toasty 90 degrees!)

But to the east of that big, hot ridge of high pressure in the middle of the nation, a big dip in the jet stream is shaping up. Exactly where it sets up will determine how chilly Vermont gets, but it will definitely turn cooler than normal.

If the center of the dip in the jet stream centers over New England, by Wednesday or Thursday it could get really raw. That would mean cloud cover, cold, light showers and highs barely creeping into the ow 50s.  That's why the National Weather Service was speculating about snow.

If the dip in the jet stream is centered a wee bit to our east, than it will still be cooler than normal, but not quite as nippy.

We're going to have to watch out for frost on several nights from midweek into next weekend.  If there's a lot of clouds around, and nighttime breezes, frost would be limited to just the coldest pockets.

If there's more clear skies and lighter winds, frost could be much more widespread.  We'd have to wait for the day before a potentially cold night to know for sure if frost is coming.

Tis the season for looking out for that kind of thing.  If you have sensitive plants you want to protect, pay attention to forecasts each day. If you hear a frost advisory or freeze warning for any night in your area, f take steps to protect those flowers or late season veggies. 

HURRICANE SAM

That chilly dip in the jet stream for us coming up is great news if you hate the idea of a powerful, dangerous category 4 hurricane hitting the East Coast. (And if you 'd love to see a huge hurricane hitting the East Coast, I hate you).  

Powerful Hurricane Sam way out in the Atlantic Ocean
on Sunday.

It's looking more and more likely that the dip in the jet stream that will lead to our upcoming cool spell in New England will steer powerful Hurricane Sam away from the United States. Bermuda and perhaps Newfoundland are still under threat. 

Weirdly, Newfoundland, way up north, has been smacked by Hurricane Larry and Tropical Storm Odette already this year.  

There's still a slight chance something weird could happen to change Sam's path, but for now, it looks prett safe in the U.S. with this one. 

As of this morning, Hurricane Sam was a monster with top winds of 145 mph.  It is expected to remain a major, scary hurricane for the next few days as it moves northwestward out in the open Atlantic.  

Sam's forward speed is slow, at least for now, so it won't be until next weekend until it will become a threat to Bermuda, if it does at all.  

Saturday, September 25, 2021

East Coast A Hot Spot For Severe Storms This Year; Vermont, Not So Much

A strong thunderstorm over Georgia, Vermont on August
11 that would go on to earn a severe thunderstorm warning
in eastern Franklin County.  It was one of a below 
average 45 severe thunderstorm warnings issued so far
this year from the Burlington, VT NWS office. 
You'd expect the place that has had the most severe thunderstorm warnings this year would be some place like tornado alley in Oklahoma or Texas, or maybe the Deep South, or the lightning capital of the nation, Florida.  

Nope. The 2021 hot spot for severe, damaging storms is in the Baltimore-Washington DC area, according to the Washington Post Capital Weather Gang. 

That wouldn't seem like the most likely place.  Sure, there is plenty hot, humid spring and summer air in that neck of the woods to fuel big storms.  But you wouldn't expect that area to be the king of severe.  

Maybe Ma Nature is fed up with the kookiness of Washington and is trying to send a message?  

A severe thunderstorm is defined as one with winds of at least 58 mph and/or hail the diameter of quarters or bigger.  A severe thunderstorm warning means a storm that likely contains those conditions was detected.  It usually, but not always means there really is a severe thunderstorm. Every once in awhile, no damage is reported with a storm that had been deemed severe.

In those cases, the storm really wasn't severe or it hit an area where nobody was around to report or even see damage.  Basically, though, if you receive a severe thunderstorm warning, you should expect such a storm and take shelter right away. A severe thunderstorm warning means trouble looms.

In the Mid-Atlantic, trouble loomed a LOT this  year.

The Washington Post says:

This map shows the number of severe thunderstorm warnings
issued by each National Weather Service local office in the 
nation. Click on the map to make it bigger and easier
to see. Image is from the Washington Post. 
"The National Weather Service office serving the Washington-Baltimore region has issued a whopping 528 severe thunderstorm warnings for its zone of responsibility from eastern West Virginia to the Chesapeake Bay.  That number even surpasses the warning count for the area around storm-prone Norman, Oklahoma, which has received a second-most 489 warnings."

The number of storm warnings in the Washington-Baltimore area is about 223 more than normal.

National Weather Service offices surrounding the Washington-Baltimore NWS district also had much more storm warnings that average.

In our neck of the woods in northern New England and northern New York, though, we've had a light storm season.  

 The National Weather Service Burlington office forecast area covers all of Vermont except our southernmost two counties and northern New York from about Whitehall on the Rutland County, Vermont border to northeast of Watertown, New York along the St. Lawrence River valley.

In this zone, there have been 45 severe thunderstorm warnings so far this year, which is 16 fewer than normal.  

Again, click on map to make it bigger and easier to see.
The departure above or below normal of severe thunderstorm
warnings issued so far this year. Image from the 
Washington Post. 
The rest of northern New England, covered by NWS offices headquartered in Gray, and Caribou, Maine have had a similarly light year.  A vast area of the Great Plains and Mid-South of the United States also had a very light severe storm year so far, relative to average, anyway. 

Up here in northern New England, severe thunderstorm warnings are usually few and far between from now until next spring, so I don't expect the number of severe storm warnings to go up much.  In general, the further south you go, the more likely there will be more severe thunderstorms before the close of 2021.  

Generally speaking, a persistent dip in the jet stream centered over the Great Lakes created this pattern.  The weather pattern favored dry, stable west to northwest winds over the Midwest that helped squelch storms.

This same pattern kept bringing storm systems, cold fronts and lots of humid air to the eastern United States, which encouraged storms. 

In northern New England, persistent ridges of high pressure over southeastern Canada often suppressed the rough weather to our south.  While this Canadian ridge mostly kept us warmer than average, it also kept those storm systems in the East from working their way far enough north to influence much. 

The cold fronts also ran into dry air associated with the southeastern Canadian high pressure, and that helped keep storms to a minimum. 

  

Friday, September 24, 2021

Hurricane Sam Really Impresses; Rapid Vermont Clearing After Rains

Clearing up super fast behind a slow  moving cold front
passing through Vermont this morning. 
 I'm watching the weather for the next few days from a temporary new perch in Yankton, South Dakota as I attend a family wedding. 

Conditions are clear sailing here, and I'm still watching the more interesting weather back home in Vermont.

A couple of really rapid things are going on in the weather today. One is completely benign, but interesting and affecting Vermont; the other is very dangerous, but no immediate threat to anyone.

The odd thing about Vermont weather today is the rapid changes in conditions are being caused by a very slow moving cold front. 

That front staggered into western Vermont in the wee hours of this morning, bringing a fairly soaking rain as expected.  Plattsburgh, just across the pond in New York got blasted by 1.4 inches of rain. Burlington got a decent three quarters of an inch.  It was  closer to a half inch around Montpelier. 

As of 9 a.m. today, that band of rain had only barely made it to the Northeast Kingdom,  and was pretty much over in the Champlain Valley. 

You know how skies ofter clear gradually in Vermont after a rainstorm ends. Not this time.  As of 10 a.m. there was a very sharp line over the Champlain Valley between thick overcast and practically clear skies.  That sharp clearing will slowly trudge east, in tandem with that cold front and rain. 

It won't be completely clear today.  Skies will be partly cloudy, and there still could be a few scattered, brief light showers popping up in the air behind this front.

I'm sure you're noticing another radical change with this weather front.  Humidity was still high as of late morning in eastern Vermont, as the front hasn't come through there yet, but that stickiness will ebb this afternoon. 

All this is a huge difference from Thursday. Temperatures soared to near record highs Thursday, and the humidity was up there, too. 

In Burlington, the high Thursday was 86 degrees, just one degree shy of the record set way back in 1895.  The low for the day was a toasty 72 degrees, adding to what has been a near record number this year of days that failed to get below 70 degrees. 

This is also unusually late for such a warm night.  It's probably safe to say that Thursday will be the warmest day until next May at least.

It'll stay on the relatively cool side through midweek at least.  It won't be frigid for the season, just coolish. Something we always see this time of year. 

HURRICANE SAM IMPRESSES

Hurricane Sam exploding into a powerhouse storm 
in the open Atlantic Ocean today. 
What was just a wannabe tropical storm yesterday morning is now Hurricane Sam way out in the Atlantic Ocean.

This storm really blossomed fast and is expected to  continue doing so. Top winds were 75 mph this morning and are expected to roar up to 130 mph or more within two days. 

This is a really fast pace for strengthening, and reflects a trend we've seen in hurricanes in recent years. Going from nothingburgers to monsters in just a very few days.   

There  has been a remarkable trend in rapidly intensifying hurricanes in the past three or four decades, researchers have concluded. The actual number of storms each year doesn't show a super clear trend, the busy seasons last year and this  year notwithstanding.

However, more and more of the hurricanes that do form turn into fast growing monsters.  Climate change seems to be behind this phenomenon. 

Rapidly growing hurricanes are a real danger if that process happens just prior to landfall, as they then hit areas not prepared for such a heavy blow. Think Michael in the Florida Panhandle in 2018 and Laura in Louisiana last year if you want examples. 

Luckily, Hurricane Sam is exploding into a power house of a storm nowhere close to land, so it can be safely monitored. At least for the moment. 

Hurricane Sam is no immediate threat to anybody's coastline, but it could at least sideswipe the northern Leeward Islands by the middle of next week.

Most current forecasts have Sam recurving northward and missing the United States late next week or next weekend.  Most forecasts, but not all.   

A meandering upper level low pressure system is expected to linger near the Mid-Atlantic states and steer Sam away from the U.S.  But if that upper low is weaker than expected, or in a different spot than forecast, then Sam could be a U.S. threat. Time will tell. 

Thursday, September 23, 2021

Tropical Start To Autumn And After Series Of Lame Tropical Storms, But Now One To Watch?

Photo taken just as astronomical autumn arrived in 
St. Albans, Vermont Wednesday afternoon.  Hints of
color in the trees, but high humidity and a tropical 
shower in the distance felt surely unseasonable.
You almost surely missed it, but there's been a good handful of tropical storms lately. It's another busy season.  

Luckily, the reason why you haven't heard of them is because the tropical storms have all been wimpy and haven't hit anything.  It's a welcome reprieve from another destructive hurricane season. That's not to say there won't be more trouble later this autumn. More on that in a minute. 

In the past week or so, Tropical Storm Odette sideswiped Newfoundland and its remnants are still meandering in the North Atlantic. Odette might briefly turn into a zombie tropical storm as it temporarily heads south into warmer water, but that won't last long.

Tropical Storms Peter and Rose also got going in the open Atlantic over the past week but strong upper level winds tore them apart. They were headed north toward oblivion anyway, so if the strong high level winds didn't kill them, cold northern waters would have eventually done the trick. 

Next up is Sam.  It's in the process of organizing itself and should be officially declared Tropical Storm Sam later today.  

Unlike the last few storms, wannabe Sam looks like it will be a powerhouse. The National Hurricane  Center forecasts Sam to be a major hurricane with top winds of 115 mph by Tuesday. 

At this point, wannabe Sam is expected to be northeast of the Leeward Islands, way out over the Atlantic Ocean. 

Most of the computer models at the moment anyway want eventually to re-curve Sam northward into the open Atlantic, well east of the U.S. Seaboard. That would be the ideal way to go. 

But not all those computer models are on board with those scenarios.  So this will be the first tropical storm or hurricane for people in the United States to really want to watch since Nicholas back on September 13-14.  

Even if Sam does become a threat to the United States, that won't happen for quite awhile.  It would take until the very end of this month or the first of October for Sam to become a real worry, if it does at all.

Of course, even if Sam avoids us, hurricane season ain't over.  It's been busy, and there's still a lot of potential for real tropical trouble in October.

There's lots of examples running through both distant and past history. Hurricane Hazel in 1954, which killed about 500 people in Haiti before crashing into the Carolinas as a Category 4 hurricane. It moved northwestward all the way to Ontario, Canada killing about 90 people in the U.S. and 80 people in and near Toronto. (Hazel managed to produce gusts to 70 mph in Burlington)

More recently, Hurricane Wilma in October, 2005 was a Category 5 storm over open waters in the northwest Caribbean. It "weakened" to a still nasty Category 3 with 120 miles winds when it eventually whipped through Florida. 

Hurricane Sandy, though technically not a hurricane when it made landfall in New Jersey in late October, 2012 was arguably that state's worst weather disaster on record. 

Hurricane Michael came ashore in the Florida Panhandle as a Category 5 storm in 2018 unleashing near total destruction in and near Mexico Beach, Florida. 

So October  an be rough.  We'll see if that happens this year. 

Meanwhile, back here in Vermont, astronomical autumn arrived Wednesday afternoon amid tropical-like humidity. It didn't really feel like autumn, did it?

It remains humid and warm today, but it IS autumn, so changes are afoot. A slow moving, wet cold front that's been lurking to our west will finally, slowly lumber through Vermont Friday.

It'll have a decent, but not extreme slug of rain with it.  We need the rain at this point, especially north, so that will be a good thing.

After that, we're down into average late September weather, with highs mostly in the 60s as we head into next week. 

Wednesday, September 22, 2021

Vermont TV Weather Viewing Changes Big Time With Retirements Of Messner, Meyer

WPTZ head meteorologist Tom Messner, an icon of 
Vermont's airwaves, announced his impending 
retirement on Tuesday. 
 WPTZ-TV on Tuesday announced the impending retirement of their long time meteorologist Tom Messner. 

The news comes just a few months after longtime WCAX-TV weather forecaster Sharon Meyer retired after 42 years. For the last 31 years she had been the WCAX lead forecaster.  

The two retirements are removing two of Vermont's most reliable weather forecasters from the airwaves. The pair are as iconic as Stuart Hall and Bird Berdan. and are both in the Vermont Association of Broadcasters Hall of Fame, for good reason.

Messner, who is expected to leave the airwaves in November, combines the expertise and institutional knowledge of legendary Alabama meteorologist James Spann, the youthful enthusiasm of Washington DC meteorologist and storm chaser Matthew Cappucchi and the warmth and good humor of Al Roker. 

He's long been called Smiling Town Messner because in every broadcast, he looks just so happy to be telling you what the weather will be like today. You can hear the smile on those occasions when he pops into radio station WIZN, often on Fridays to update you on the weekend forecast.

That happiness is infectious, and viewers know it.  As WPTZ points out, Messner was the winner in the annual Seven Days readers poll as the region's "Best Meteorologist" every year that category existed in that newspaper. 

In a statement released by WPTZ Tuesday, Messner said, in part, "I'm honored to have served my neighbors and our communities and to have the privilege to personally meet so many of our viewers throughout my 31 years at NBC5.  Your amazing support and trust have allowed my family to build a home and life in a place that we truly love. I'm forever thankful."

Unsurprisingly, tributes poured in Tuesday on the news of Messner's impending retirement.

"Tom's been a fixture in our homes and a patron to all that we love about our (Great) Lake Champlain. Tom, congrats on all that you have accomplished and on how you've done it.... with expertise, wit and class," U.S. Sen. Patrick Leahy D-VT tweeted. 

Messner will continue on at WPTZ as Chief Meteorologist until late November.  He'll also make guest appearances on the television station from time to time.  He's not moving away, and will continue his very active role at Feeding Chittenden. 

Another TV Vermont weather icon,
Sharon Meyer, retired from her 
duties at WCAX back in June.

"This isn't really goodbye, it's I'll see you around," Messner said on a Tuesday WPTZ broadcast.

As noted, Messner's announcement is the second high profile Vermont television weather departure this year.  Sharon Meyer's long reign as the lead forecaster at WCAX-TV.

On air, Meyer always exuded both warmth and unflappability. Except when there were close lightning strikes.  She didn't seem to like those, which made her a lot smarter than most weather geeks I know, including me. 

Watching a Meyer on WCAX was like a friendly chat about the weather over tea with a trusted friend.  

Another reason why Meyer is such a Vermont broadcasting gem is because she loved to take us with her as she traveled Vermont and the the world, and brought us outdoors with her in sunshine and ugly storms.  Meyer is always so inviting on air. 

The legendary Stuart Hall picked Meyer to do the 11 p.m. weather at WCAX in 1986.  When Hall retired in 1990, Meyer became the lead weather person at WCAX, a role she dutifully continued until this June.

Like Messner, Meyer never really disappeared, thank goodness. We still see her on WCAX gardening segments and in other appearances. 

The departures of Messner and Meyer fortunately do not leave Vermont lacking in talented TV meteorologist.  I don't want to list them all, for fear of leaving somebody out, but we do remain in excellent hands with the on-air meteorological talent on the Green Mountain State's airwaves. 

Television stations in the Vermont market would be wise to do everything they can to keep these meteorologists here. 

Tuesday, September 21, 2021

Does Climate Change Make Winter Cold Snaps Worse? More Evidence On That

Frozen Texas last February.  A new study indicates 
climate change might occasionally "stretch" the winter
Polar Vortex, increasing the chances of freeze 
disasters like this one. 
 It's a little early to be thinking about intense winter cold, but new information suggests that a warming Arctic puts us at risk of sharper, more dangerous cold snaps.  

This idea has been the subject of debate among climate scientists for years, and I've brought this up from time to time. But new information paints a weirder, darker picture of that horrible cold wave last February in Texas.

Remember that? Temperatures fell to record, sometimes unprecedented levels across much of Texas, and in  big sections of the Plains and South for that matter. That's the cold wave in which Texas Senator Ted Cruz briefly fled to Cancun to escape the cold until nationwide derision brought him back to frigid U.S soil.

Anyway, to review. You've heard of the Polar Vortex, right? It's that roughly circular pool of frigid air that roams the Arctic, especially in winter. If it moves closer to the United States, it gets cold here. If it moves closer to Europe, it gets cold there.

All that is perfectly normal is just the way the atmosphere works.  Except lately, the polar vortex seems not to be always working the way it is supposed to.

This brings us to a recent news about the Polar Vortex.  As the Washington Post reported early this month:

"In a study released (earlier this month) in the journal Science, the devastating Texas cold wave in February is linked to a stretching of the polar vortex in the stratosphere miles above ground. This stretching mode, only recently categorized, has become more common over the last 40 years, the paper finds, and the increase may be related to human-caused climate change."

When you stretch the polar vortex, or split it in two, it can rearrange the jet stream to direct frigid air from the Arctic right down well into the mid-latitudes, including the United States, including Texas.

Until now, scientists have looked more at how splitting the polar vortex into two or more pieces can cause severe mid-latitude frigid outbreaks, because often one of the pieces of the polar vortex in this scenario sinks south, bringing the gelid air with it. 

The new study indicates that a stretched polar vortex delivers icy air south more effectively than a vortex that has been split up. That stretched vortex is what happened in Texas and much of the rest of the middle United States last February.

The study also suggests that this stretching of the polar vortex has become more common since around 1980, the Washington Post reports. 

It appears that changes in Arctic sea ice and snow cover in far northern Europe and Asia,   seem to be contributing to this more frequent polar vortex stretching.  Scientist think this is related to climate change (of course!) but the view is not unanimous.  It could be just natural variability.   

However the early read on this is there might be some natural variability involved, but climate change seems to be screwing around with the polar vortex, too.

Which means we will probably be faced with the following scenario: Winters in general will continue to get warmer. But those more often than not warmer winters will be punctuated by periods of extreme record cold.

And you never know where these Arctic plunges will occur.  Last February's intense cold pretty much missed us here in Vermont.  We might not be so lucky next time.

Like everything else involving possible links to climate change, this messes up all kinds of things for us humans.

The obvious is the suffering and deadly consequences of these intense winter cold spells, as we saw in Texas last year. 

Another issue I thought of is this.  There are few bright sides to climate change, but maybe crops and other plants that used to be confined to the South can spread north a bit. Not if a super bad cold snap one every couple of few winters kills them off. 

The sad fact of the matter is climate change will continually provide unhappy, sometimes dangerous surprises.

Monday, September 20, 2021

Fog Season In Vermont; Fog Attacks Power Grid On West Coast

In this morning visible satellite photo, you can see
fog hugging the Connecticut River Valley, and parts 
of the Winooski and White River Valleys. You can 
also see fog running up the valleys that go along
the tributaries of these rivers.
 I'll get to the first part of the above headline first, because - huh???   

Usually, when electricity goes out for weather related reasons, it's because of high winds or lightning.

But in the San Francisco Bay Area on Sunday, 29,000 lost power because of a decidedly non-violent weather event: Fog and drizzle.

In the Bay Area, it generally doesn't rain in the summer.  According to television station KPIX, dust and debris settles on power lines and power equipment over the dry summer months.

  When dense fog and drizzle finally arrives with the first autumn storm, as it did Sunday, the moisture interacts with the debris and dirt to cause flashovers. And Voila! power failures.

I mention that weird Bay Area weather story in part because here in Vermont, we're in peak morning fog season. We don't have to worry about fog-related power failures, because it rains so frequently here in the summer that dust and debris don't accumulate on power equipment.  

Here's why we get so much morning fog this time of year:  The ground and the water are still warm from the summer. Nights are getting cooler, especially the nights with clear skies and light winds, like we had last night. 

Warmth and moisture rising from the ground and water hits the cold air and condenses into fog.  Often thick fog.  You really have to be careful driving early in the morning on days like this because of the patchy nature of the fog.

You're cruising along and you can see for miles and suddenly you're in a fog bank and you can't see a thing. If you're not paying attention and you're unlucky, you then crash into the invisible car in front of you in this pea soup. 

On the literally bright side, the sight of morning sun piercing the fog is gorgeous, and makes for some absolutely stunning photography.  So it's probably a good idea to have your camera with you on foggy mornings.

This morning was a classic Vermont fog morning. Last night, as noted, was clear and a bit chilly. Dense fog filled many of Vermont's river valleys. I noticed towns like Montpelier, Morrisville, Lyndonville and Springfield all reported dense fog this morning. 

Meanwhile, my place is perched on a hill in St. Albans. Nothing but blue sky out there for me. 

You can see the fog outlining river valleys in the satellite photo in this post. 

The next few nights will probably have less fog than this morning, because breezes will be picking up.  Overnight winds tend to disperse fog before it can get too dense.  The fog for the next few mornings will probably limited to the deepest valleys most protected from the wind.

However, we're likely to have more foggy mornings, at least until most of the leaves are off the trees.  Leaves emit moisture, and losing those means a source of water for the fog goes. Also, once we get into late autumn, it's more often than not too windy to sustain morning fog. 

 

Sunday, September 19, 2021

For Vermont Storm Addicts Out There, A Recent Video

Back on September 8, some strong to severe thunderstorms rolled across Vermont

As usual, I like to take videos of said storms. The video in this post is around South Burlington and Burlington of the storm and its aftermath. 

Bonus: Part of the storm's aftermath was absolutely gorgeous.

 I shot the storm with an iPhone and something is funky with the microphone, so sorry about the sound issues.

Snarky me often calls videos of big storms such as violent hurricanes, tornadoes and floods, "weather porn."  Although fun to watch, this particular video is probably more R rated. Sexy enough, but not weather porn.

By the way, word to the wise. Don't Google the phrase "weather porn."  It leads you to some really weird stuff. 

Anyway, back to my storm video.  Many mobile users have trouble seeing videos on this here blog thingy when I insert the video into the blog. If you have that trouble, just click right here on this hyperlink to view. 

If you see the video displayed click on the arrow, then the YouTube logo for best viewing.  And as those pesky YouTubers say, feel free to subscribe to my channel.

Here's the vid!



Saturday, September 18, 2021

Definite Cracks In That "Never Ending Summer" Regime

Weather patterns nationally and locally
are finally beginning to transition to
one more typical of autumn
Here in Vermont and across most of the nation, summer has continued unabated well into September, with no sign that the season is transitioning to autumn.  

Until now.

The pillars of summer's dominance are falling like dominoes, as rain and chilly air begin to make real inroads. And did somebody say snow?

Relax. There's no snow is in the Vermont forecast just yet. I'm talking about the western mountains. 

Normally, as we go into autumn, the jet stream gets more energetic and begins to slip south.  This allows larger storm systems to form and create widespread rains. It also increasingly lets cold air trapped in Canada loose,  sending it down on the United States.

During the first two weeks of September, t seemed like this transition was not showing the usual signs of starting.  Now, it has.

One welcome aspect of that shift happened in drought and wildfire stricken British Columbia, and Washington and Oregon in the United States.

As that jet stream sank south, it allowed an atmospheric river of moisture from the Pacific Ocean to smack into these areas. Some areas have seen up to four inches of rain. This will end or at least seriously reduce the risk of wildfires in these areas.

Some of the rain is brushing far northern California, but unfortunately most of that state will remain in drought and wildfire risk for some time yet.

It'll be cold enough behind that western storm to unleash a little snow by Monday in the high elevations of Idaho, Wyoming and Montana.  That's normal for this time of year, but still a sign of the season.

The first frost advisories of the season were up this morning in northern Minnesota, too. Again, normal, but still.

Here in Vermont, long range forecasts for summer warmth through the end of the month have fallen by the wayside.  Warm weather will not last as long as previous forecasts suggested. That's not to say we, or other parts of the nation won't have spells of warm weather between now and October.  It's just that it won't be consistently warm anymore. 

There's no sign of extreme cold coming up, but you will feel autumn's onset, especially toward the end of next week.

Before then, a brief intrusion of cooler air will drop temperatures into the mid and upper 30s Sunday night in the coldest hollows and the 40s elsewhere.  Once again, that's nothing unusual, but will still be the coldest weather since the end of May or very early June.

But at least it will be sunny and VERY pleasant Sunday and Monday, too.  But a big dip in the jet stream is coming, though there's a lot of argument about when later in the week that will happen.

When it does, you'll notice a transition to serious fall weather. Again, nothing wild for Vermont in September, but it sure won't be beach weather!  

Friday, September 17, 2021

Giant Sequoias Greatly Endangered By Forest Management, Climate Change And Current Fire

The famed General Sherman sequoia, probably
2,500 years old, wrapped in aluminum foil
in an attempt to save it from an oncoming
wildfire this week. Photo from National
Park Service.
It comes down to this now, apparently.

We're killing living things that are thousands of years old through climate change. Wildfires are closing in on California's giant sequoias as I write this. 

As the BBC reports:

"Officials fear the fire could reach the Giant Forest, a grove of some of the world's biggest trees, within hours. 

The forest hosts some 2,000 sequoias, including the 275-foot General Sherman, the biggest tree by volume on Earth and about 2,500 years old."

In desperation, crews have wrapped the base of the General Sherman and other giant sequoias in aluminum foil in a last ditch attempt to save them. 

Sequoias are actually pretty fire resistant.  Over the centuries, many wildfires have burned through sequoia groves. 

But those fires burned along the ground, perhaps scorching the lower trunks of these trees but leaving the mid and upper parts of the trees green.  Sequoias usually lack lower branches that can catch fire and then spread flames upward through the tree.

All this leaves sequoias pretty much intact in a wildfire.  

What's new is the and aggressive wildfires that have roared across California in recent years. These fires are so intense that an entire sequoia can go up in flames as flames shoot ridiculously skyward. Those flames burn entire sequoias, destroying them.

A combination of poor forest management that allowed dense, flammable undergrowth to flourish, and climate change, threatens the existence of sequoias.

Since sequoias have a storied relationship with Americans, that would be yet another big climate change tragedy on top of many others.

Last year, an intense wildfire killed more than 10,000 sequoias, representing nearly 14 percent of the world's population of these trees, noted NPR in a report aired this morning. The dead sequoias are now black, tragic, immense dead poles sticking high up into the air. 

With the new fire looming today, all we can do is hope that firefighters can keep the most destructive flames at bay and save the sequoias, including the beloved General Sherman. 

Perfect Weather: In The Eye Of The Beholder But Thursday Was A Good Candidate

I paused in under a sugar maple in my St. Albans, Vermont
yard yesterday to take note of the most perfect 
weather day of 2021, at least in my opinion
My bad.

Yesterday morning, I should have issued a Perfect Weather Warning for central and northern Vermont.

What wasn't to love about Thursday?  Deep blue skies decorated with just a few lovely clouds, wonderfully comfortable temperatures, a slight breeze, early hints of fall color glinting in the pristine air. 

Kinda why we live in Vermont, huh?

I declared yesterday the best weather day of 2021, at least in northern and central Vermont.  Sorry, far southern Vermont, you had a few extra clouds.

Perfect weather is in the eye of the beholder, of course. Some people think 95 degrees with high humidity is the best conditions possible. Others prefer winter cold and blizzards as their best weather.  There's a few crazy storm chasers out there who think perfect weather consists of powerful tornadoes marauding across the Great Plains landscape.

My definition of perfection was yesterday, though. Dawn broke with temperatures in the low 50s.  That meant it was comfortable for sleeping, but the air that got into the house through open windows wasn't too cold.

There was patchy ground fog around, and it's always wonderful to see the sun's rays pierce the fog brilliantly as it lifts.

The day went on to give us deep blue sky.  Air behind a cold front the day before came straight down from Quebec, shunting western wildfire smoke away from us.  Even from a distance, because there was no haze, Vermont's Green Mountains looked, well, green. 

The now lower sun angle of September made the light feel warm, but not hot. Temperatures climbed into the mid 70s by afternoon. I spend some time working rather hard digging in the garden.  I had plenty of energy because there was no heat or humidity to drain me. 

We have so many gloomy days over the course of a year in Vermont that a day like Thursday was one to savor. 

Delightful weather can treat us any time of year, of course.  But September is a prime great weather month here in New England. 

The summer heat has relaxed, so temperatures are often comfortable.   You can get weather like thi sin the spring, too. But spring is more volatile than September.  Spring storm systems, still energized by a just ended winter, tend to give us more extremes in the spring.

Which is why you need to brace for late season snows, severe thunderstorms and bouts of heavy rain in the spring. 

In September, storm systems in general are weaker because they haven't ramped up from the summer doldrums yet. Sure a cold front can still sometimes stir up some nasty thunderstorms every once in a great while. Wednesday was an example of that.   

Those days are exceptions, though.

The only extremes we get in September are when hurricanes venture north into New England, which is fairly rare. Of course when a hurricane does happen, things go from unpleasant to disastrous in a hurry.  Nobody wants a repeat of the Great Hurricane of September, 1938, for instance.

Overall, though, September is a moment on the weather timeline to pause and enjoy.  The sky is still blue the gardens are still providing a wonderful harvest. The air is often soft and bright and clean.

While we might not have the perfection of Thursday coming up every day for the next couple of weeks, there's plenty of wonderful weather in the cards.

The clouds you saw in the sky this morning should at least partly clear by this afternoon, giving us another bright, comfortable day. 

Though Saturday will features scattered showers and maybe a rumble of thunder, especially north, it will by no means become a washout. Sunday looks absolutely delightful and could rival Thursday for awesomeness.

The first half of next week looks nice, too.

Enjoy it.  Soon enough, you'll be shoveling snow, scraping ice off your windshield while you desperately try to warm up the car.  You'll be blasted by icy winds, and you'll fall and hurt your hip on your slippery driveway. Your heating bills will skyrocket, and cabin fever will inspire murderous thoughts about your loving significant other. 

Put that out of your mind. When the sun comes out today, put on your sunglasses, a little sunscreen and bathe in that wonderful early autumn air.  

Thursday, September 16, 2021

Vermont Storms Behaved As Expected; Summer In Autumn Resumes

As we've seen several times this month, a generally stormy
Vermont day ends with a big sunset. View from St.
Albans, Vermont last evening.
 Well, it could have been worse.

Severe thunderstorms developed pretty much as expected across the southeastern half of Vermont Wednesday, doing the usual damage to trees and power lines in some towns throughout the region. 

The strongest cluster of storms at least in Vermont, started in western Rutland County and moved east-northeast and crossed the border into New Hampshire part way between White River Junction and St. Johnsbury. 

Trees and branches came down along this line in Middletown Springs, then heading over the Green Mountains to Bridgewater (near Killington), then up toward Ryegate and Newbury in the Connecticut River Valley.  

Though forecasts called for a low risk of tornadoes with Wednesday's storms, there's so far no evidence anything of the sort happened, at least in Vermont.   Preliminary indications are that it was all straight-line winds. There was briefly a tornado warning in southern Maine, but it's unknown if one actually touched down.

Northwestern Vermont, as expected, missed out on the "fun" on Wednesday.  Thunderstorms rolled through early in the morning, and a few brief downpours zipped on through in the early afternoon.  My rain gauge in St. Albans caught right around a half inch of rain Wednesday.

That's pretty much it for rain for at least a week, aside from some hit and miss stuff that might come along Saturday afternoon and evening.  

The front that caused the storms was producing heavy rain in southern New England this morning. There were even a few severe thunderstorms on and near Cape Cod. That bad weather is slow to move on  in part because a big, fat ridge of high pressure is building over the northeastern United States and southeastern Canada.

Hibiscus plant still thriving out on my St. Albans, Vermont
deck as warm September weather continues. 

The front will wash out eventually as a tropical system moves by offshore, not bothering with  us at all.

This big, fat high pressure will ensure that summer in September continues on for at least a week, if not more.  

Aside from those pesky Saturday showers,  expect a fair amount of sunshine for quite awhile.  It'll be just sort of warm for this time of year at first. Highs each day through Sunday will be in the 70s, which is a little above normal. 

It'll get even toastier by the middle of next week.  Highs have a shot of reaching the mid-80s, at a time of year when barely 70 degrees just about does it for daytime highs. 

I'm not sure how all this warm weather will affect the fall foliage season.  The best colors come after sunny Septembers that have plenty of chilly nights. We are more or less getting the sun, but certainly not the chill. It STILL hasn't been below 50 yet this month in Burlington, and it doesn't look like it will get that chilly in the foreseeable future.

We'll get slapped in the face by cold weather eventually, but it isn't going to happen any time soon. Your garden is safe from frost.

Wednesday, September 15, 2021

UPDATE: Severe Storms Sweeping Southern Central Vermont; Will Continue Rest Of Afternoon

Best chance of severe thunderstorms 
today is in yellow shaded area.
UPDATE 5:30 p.m. Wednesday

It's just about over for Vermont, anyway, as of 5:30 p.m.

Most if not all the severe storms have moved east of Vermont, though a few strong ones are still possible in far southern Vermont.

The only thing we really have to watch out for now is the possibility of flooding in Bennington County.

Just over the border into New York State from Bennington County, up to four inches of rain has fallen and more is coming down. Flash flooding, some fairly serious, is ongoing there.

One last batch of heavy rain is headed toward Bennington County, and that could be enough to set off some local flash flooding in that area. Iffy, but possible.

A pretty good slug of rain seems to be headed toward central Vermont, too, but it won't be enough to cause flooding. 

As usual, far northwestern Vermont, pretty much the only part of the state that needs rain, kinda missed out. My rain gauge in St. Albans collected a half inch of rain today.

No substantial rain is in the forecast for the next week. 

Several towns in southern and eastern Vermont have reported tree damage from severe thunderstorms today. 

UPDATE: 2:30 p.m. Wednesday 

As of 2:30 p.m., the expected severe storms have developed as expected.

They seemed to have formed into two lines.

The stronger of the two was further south, from near Rutland northeastward to east of Montpelier.

Many of these storms in this southern line so far have remained somewhat separate from one another, giving rise to the risk that they could more easily spin, and potentially drop a quick tornado.

So far there's no evidence of this, but severe thunderstorm warnings have been flying down in that neck of the woods.

This line of storms will slowly sink southward while strong to severe storms race northeastward along that line. 

The second line ran from Chittenden County to the Northeast Kingdom and was following roughly the same pattern as the one further south.

Although not as strong as the southern line, some of the storms in the northern line are quite strong, and could become severe as the line slowly sinks south and east.

Far northwestern Vermont is escaping this with showers, and possibly a rumble of thunder for the next couple of hours.

I won't be chasing these storms today because I got out of work a little to late to catch up with them. 

PREVIOUS DISCUSSION
 
 Up here in St. Albans, Vermont dawn came with thunder, lightning and downpours, part of that set up for a stormy Wednesday. 

The morning storms up here hinted at today's set up, which has been consistently forecast for days now. Southern Vermont is the storm target.

I know that sounds a bit strange, since all the activity early this morning was up north and the south stayed dry. 

However, when thunderstorms go through a particular spot early in the morning,  more stable air is usually left in their wake.  That's the case here, and will help to squelch storms later this morning and afternoon. Lingering clouds from the storms will hold temperatures down a bit.

Plus, the morning storms were an indication that northwestern Vermont is closer to the cold front that will cause today's problems. The cold front will come through here early enough in the afternoon so that storms won't have a great chance to develop much in the heat of the day.

Still, the north could see a few gusty, rainy storms later today, and non-thunderstorm southerly winds could gust to 40 mph in the Champlain Valley before the cold front arrives, but let's not focus so much on that.

Roughly the southeastern third of Vermont is the target, along with much of New Hampshire, southwestern Maine and the Hudson Valley of New York.

In these areas, some sun will continue to shine into the afternoon.  It has turned humid.  Temperatures will pop up into the low 80s.  Those are many of the ingredients you need to set things off.

Also, on the check list is that approaching cold front to create lift in the atmosphere that would aid and abet storms. And strong winds aloft to help maintain the storms.  The winds high above will also change direction with height, so most of the ingredients are there. 

Strong straight line winds are the main threat, but we'll have to watch for hail and even a brief spin up tornado. A quick twister is possible, though rather unlikely. 

The low chance of tornadoes will come if supercells develop.  These are rotating thunderstorms, not attached to each other like the lines of storms we usually see.  If that happens, there could be a few spin ups.

Today's set up, though, suggests that any individual supercells that form will fairly quickly merge into a line of storms.  That reduces the already low tornado risk somewhat more, but also increases the chances of strong, damaging straight line winds.

I do think some wind damage reports are inevitable today in the areas I talked about.

It looks mid afternoon to early evening is the hot time for the storms today in southern Vermont. They probably will go later than that once you get into New Hampshire and Maine. 

Low but not zero chance of tornadoes today in
green and especially brown shaded area.
Let's insert the usual caveat here:  While most everyone in Vermont, especially southern Vermont, will see showers and storms, not everyone will be "lucky" enough to be hit with a dangerous, damaging storm. The actual scary ones will be hit and miss. 

Torrential downpours are likely with the storms. Though there might be some street flooding and local minor washouts, the storms should be moving along just fast enough to prevent severe flash flooding.

For those under the risk of severe storms today, you know the drill.  Just do your normal stuff, but have a way to get storm warnings, like a weather radio or a reputable source like major local news media like TV and radio stations. 

If you get a severe thunderstorm or God forbid a tornado warning, head indoors immediately.  In the unlikely event of a tornado warning, the basement is your best bet. Failing that, a windowless interior room on the first floor of a sturdy building is best. 

It's kind of late in the season for this type of severe weather outbreak, but these things can and do occur in September every once in awhile.

This will all be out of our hair by tonight, and the forecasts still calls for several days of warm, mostly dry weather. (Could be a few light showers Saturday, we'll see).

Weather geeks out there might have heard of one run of the American computer model known as the GFS that has a strong hurricane racing northward through New England around September 27.  That run of the computer model depicts a hurricane similar to the Great Storm of 1938.

Before you get your panties in a bunch with panic, I wouldn't worry about that just yet. Let's listen to famous tornado chaser Josh Morgerman (icyclone on Twitter), who does have a way with words. "You New Englanders need to cool it with your 1938 fantasies, ya here? Put the nudie magazine (00Z GFS) away."

Chances are there will be some sort of tropical system off the East Coast sometime toward the end of the month, but first, we don't know for sure there will actually be such a system, and two, if there is a storm the forecast is so long range as to be almost meaningless. For the record, a subsequent run of the GFS six hours after the above mentioned one showed a hurricane passing well east of New England.

I'd give it another 10 days.  If the models are still advertising a New England hurricane then, that's the time to worry. But right now I'm really betting against such a scenario.


Tuesday, September 14, 2021

Wednesday Vermont Storm Update And Nicholas

Best chances of severe storms Wednesday look to be in
the yellow zone. Marginal risk in dark green. Graphic
is from the National Weather Service in South 
Burlington, using data from NOAA's Storm
Prediction Center.
We're still looking at just one day over the next week or more in which we here in Vermont could have some tricky weather.  

That's tomorrow.  

The forecast still calls for the risk of some strong to severe storms, especially in southern and eastern Vermont. 

You know the drill: Some storms might have damaging winds, torrential downpours could set off a local flash flood or two, and the lightning will be dangerous.

You know this part of the drill, too: Southern Vermont will be the real target, while northern Vermont, especially the northwest, escapes the weather to an extent. 

The best chance of severe storms for now looks to be south and east of a roughly Rutland to St. Johnsbury line. Still, there could be a few isolated instances of strong winds in central and even northern Vermont. In this area. NOAA"s Storm Prediction Center has at least a slight risk of severe storms Wednesday afternoon and evening.

The Storm Prediction Center has been toying with the idea of boosting the risk level of severe weather to "enhanced," which is level 3 in a 5 point risk scale. But due to some uncertainty in the forecast, they're keeping it at slight risk for now. That's level 2 in the 5 point risk scale.

As a warm front comes through tonight, you might be awakened by the sound of rain on the roof and maybe a few rumbles of thunder. Nothing severe with that batch of showers and storms, though. 

When you get up tomorrow morning, the air will have a more humid feel to it. That'll set us up for the storms as a cold front slowly comes in from northern New York.

Up in northwest Vermont, lots of clouds will hold down instability, and the best upper air support for strong storms will be to the south. So, there could be some downpours, some lightning, maybe just a little wind up in the that neck of woods.

The morning and early afternoon will feature at least some sun in southern Vermont, which will help to make the atmosphere more unstable.  That means it'll be easier to form strong updrafts that give rise to those towering thunderstorm clouds. 

Stronger winds aloft will help maintain the storms.  When the upper level winds aren't very strong, the towering thunderstorm clouds remain more or less vertical.  That means the warm moist updraft with thunderstorms gets mixed up with the cold downdraft with the storm's rain, and the overall storm falls apart. It's too disorganized.

If there's strong wind aloft, the big towers of the thunderstorms are tilted. That means the warm, wet updraft that sustains the thunderstorm stays on one side of big towering cloud, while the cold, gusty downpours stay out ahead of the updraft, and doesn't interfere with it.   The updrafts and downdrafts don't get mixed up with each other, so the storm can sustain itself and get stronger.  

That's the kind of deal southern Vermont faces tomorrow. It's a pretty typical setup for strong to severe thunderstorms. 

Those strong upper level winds will also change direction with height. That could cause some storms to rotate. Which in some cases can actually spin up a tornado.  The Storm Prediction Center has a very low, but not zero risk of a couple tornadoes in southeastern Vermont, southern New Hampshire and southern Maine Wednesday.

But the main threat will be damaging straight line winds with the storms.

After all that goes by, we stay in some benign, warm weather for several days at least.  There could be a couple showers Saturday, but nothing widespread. Temperatures on many afternoons over the next week will flirt with a summery 80 degrees.

NICHOLAS

Tropical Storm Nicholas managed to increase to hurricane status for a short time overnight just before making landfall in Texas.  Top winds at landfall were 75 mph.

But as we mentioned yesterday, wind isn't the big problem here.  There was a fair bit of storm surge flooding overnight.  Most of the streets in downtown Galveston, Texas were under water from the surge that came in from the Gulf of Mexico, and there is storm surge damage throughout the mid-Texas coast.

Nicholas is forecast to more or less stall over 
Louisiana, which will unleash another disaster
on the state, this time devastating floods.
The even bigger problem is the torrential rain falling on the upper Texas coast and moving into Louisiana. They're still forecasting up to 20 inches of rain. 

Video from Live Storms Media from the Texas Coast last night showed an incredible amount of water pouring from the skies on top of the storm surge.  

Nicholas will diminish to a tropical depression, but will nearly stall over Louisiana this week. That will unleash tremendous amounts of rain on the storm-beleaguered state, and they will have another big disaster on their hands, this time from flooding. 

Even though the wind wasn't extreme, more than a half million people are without power in Houston, surrounding areas and into Louisiana. That doesn't include the people in Louisiana still without electricity from Hurricane Ida a few weeks ago.

The United States really seems to be a target for hurricanes and tropical storms this year. So far, eight such storms have hit the U.S.  

After Nicholas, there's nothing in the next couple of days that is threatening the United States, but there's still plenty of time left in hurricane season for more to hit.