Western Snow Drought. Florida Snowier than Utah. But Is Relief Finally Coming To Rockies?

Judging from the white residue on the rock in the top
photo, Lake Powell was already very low several months
ago. Bottom photo is a recent picture. A Year Without
a Winter is creating dangerous water shortages
in much of the West 

While the East is having the kind of bitter cold and winter storms not seen in years or even decades, the West is enduring the Year Without A Winter. 

And that's getting worrisome. 

 Most of the Rocky Mountains are already in drought. This winter out west has been anything but wintry. The region has experienced springlike temperatures all season and it has barely snowed. 

Unless it snows hard and soon, the ground will dry out quickly in the spring, setting the stage for a horrific fire season.  Reservoirs and other water sources could get critically low. 

Wyoming, Utah, Nevada, Idaho and Colorado have all been running at least six degrees warmer than average this winter.  

Precipitation  is also running below normal this winter through most of the Rocky Mountain region. 

Much of what little has fallen came as rain, instead of the snow that normally falls. You need that deep mountain snow cover to feed reservoirs and to keep the forests fairly moist heading into wildfire season.  Thawing has been seen at elevations of 10,000 feet this winter, a time of year when snow should be continuously piling up on the mountaintops

Salt Lake City, Utah only had a trace of snow during January.  Marianna, Florida had 1.3 inches of snow in January. Snow flurries fell as far south as Sarasota, Florida.  

It didn't rain much in Utah either. Salt Lake City had 0.42 inches of precipitation in January, compared to a normal of 1.43 inches. On Sunday, SLC  tied their record high for the date at 64 degrees.

 As the  Washington Post tell us: 

Jon Meyer, the assistant state climatologist in Utah, said that Utah is 'officially in uncharted territory' in terms of the low snowpack,

It's even weirder than you'd think in Utah. Usually there's little evaporation during the winter in Utah as the landscape is normally mostly frozen or covered in snow. Oddly warm temperatures have left bare ground, and that is driving up evaporation rates, making drought worse. 

The snow pack in Washington State was just 26 percent of normal as January closed. The state was slammed by atmospheric rivers in December But those storms were so warm that rain fell almost all the way to the summits of the Cascades and volcanoes in the Pacific Northwest. 

In Colorado, snow cover as of February 1 was the lowest on record for the date, if  you measure through federal satellite data that began in 2001. Most snow monitoring stations in Colorado with records stretching back to the 1980s are at record or near record low levels, Colorado Public Radio reports. 

The lack of precipitation this winter in the headwaters of the Colorado River is the worst in the region. The Colorado River water ends up in Lake Powell, which stores \water for millions of people. Lake Powell water is also released to generate hydropower. The reservoir is the second largest in the United States.

So yes, Lake Powell is pretty damn important, and it turns into a crisis if it empties out too much. Which it is poised to do. 

Lake Powell is only about 25 percent full, and the water supply flowing into Lake Powell will be just 38 percent of normal through July, if current projections hold. 

In California, the winter got off to a pretty good start with some heavy storms depositing inches of rain and feet of snow in the Sierra Nevada mountains. But that moisture supply shut off in January. Statewide, snow water equivalent was only about 59 percent of normal as of January 30. The Sierra snowpack supplies about 30 percent of California's water needs.

Luckily, reservoirs in California are still full because the previous three winters were on the wet side. California is not in drought, though abnormally dry conditions crept into the extreme northwest corner of the state recently. 

The ski industry has taken a hit out west, too.  Vail in Colorado, for instance, is enduring a 20 percent drop in skier visits this winter. 

It's usually the western ski areas that are buried deep in snow while the east struggles. Usually, it's the western resorts that enjoy a few hundred inches of snow per winter. Not this year.  Mount Baker which has a national record for most snow in one season, with 1,140 inches, in Oregon, had only 280 inches of snow through the final days of January.

For perhaps the first time in memory, it's an eastern ski area that was, at least at the end of January, leading the charge. By the time January closed out, Jay Peak in northern Vermont had already collected 300 inches o snow. 

 SOME RELIEF

The persistent high pressure over the western U.S. that blocked storms from affecting the western third of the United States is breaking down, and storms are finally starting to move in. Forecasts give almost everyone in the Rocky Mountains region some precipitation over the next week.

Some areas of the Rocky Mountains are in for more than a foot of snow. The Sierra Nevada in California might see a few feet of new snow in the coming 10 days or so.

Any rain or snow will be welcome, but it's unclear how much precipitation will drop and how long the stormier pattern might last.

Still, the West needs much above average precipitation before the winter and early spring rainy season peters out. So far, at least, none of the storms in the forecast look exceptionally large .

The West might be looking at a long, hot, dangerous summer. 

 

  

 

So What Happens When All That California Snow Melts?

 A week or two ago, I wrote about how the healthy early March snow in Vermont slightly increased the threat of flooding this spring. 

Snowbanks along Interstate 80 in Donner Pass,
California recently. 

So what happens when 50 or feet of snow has to melt under the strong rays of the spring sunshine? 

I'm not sure, but unfortunately, Californians will soon find out. 

The storms are still rolling into California, maybe with less intensity and frequency than they did a few weeks ago, but regardless, bad enough. A warm atmospheric river recently melted a fair amount of snow in some of the blizzard-wracked foothills. That was enough to unleash some serious, damaging floods.

The Sierra snows should be just starting to melt by now. But snowstorms and continued below normal temperatures are continuing. Probably for at least another week or two. Instead of getting rid of some of the snowpack and its water, more additions are coming. 

At least another foot or two of new snow is expected in the Sierra Nevada mountains of California between this morning and tomorrow afternoon. 

The snowpack in the Sierra Nevada typically peaks around April 1. But forecasts indicate that peak might come later this year, as below normal temperatures and above normal precipitation are forecast to last in California at least into mid-April. 

The later we get into spring, the greater the chance a heat wave could strike. That would unleash a lot of water.

There's plenty of water in that snowpack, that's for sure!

As of the middle of last week, some of California's ski areas had received more than 650 inches of snow this season. That's more than 54 feet of snow. Most of that snow is still on the ground. 

The amount of snow in the Sierra Nevada mountains in California exceeds or will soon exceed that of the winters of 1969 and 1983, which until now had been the benchmark for the most snow you can get. 

The results probably won't be good. Especially if California flips to the kind of weather they've seen later in spring - very hot weather. 

As the Washington Post reports: 

"'It is important to understand that we are in uncharted territory,' said Jeffrey Mount, a senior fellow at the Public Policy Institute of California's Water Policy Center, in an email. 'The amount of water tied up in snow in the watershed is about twice the average amount of runoff in an entire year.'

FULL RESERVOIRS/NEW LAKES

When the 1983 snowpack melted, it flooded 100,000 acres of farmland and temporarily re-created a lake that had been drained generations earlier.    Lake Tulare, as it was called,  had been the largest west of the Mississippi, even bigger than the Great Salt Lake more than a century ago. But, it was drained for extensive farmland in California's Central Valley.

However, Lake Tulare partly reappears in especially wet and snowy years, so, it will probably re-appear this year, says that Public Policy Institute.

  It took two year after the 1983 event to pump out the water in temporary Lake Tulare and restore it to cropland, according to the Public Policy Institute.

If Lake Tulare comes back this year, as seems inevitable, it's not all bad. At least a small proportion of it will seep into underground aquifers, which have been over-pumped for decades to feed agriculture, mostly. 

What would have been better for California would have been a series of several winters that were somewhat wetter and snowier than average. That would have allowed reservoirs to fill, but not overflow. Several consecutive sort of wet but not overly soggy and snowy winters would have built back some of the depleted groundwater in California.  

Instead, California has had an epic winter.  Too much of a good thing. This winter's weather has definitely helped erase, or at least sharply dim the state's long-lasting drought. But a lot of this year's runoff can'r be saved up. There's too much of it.  

Reservoirs are filling up, and there's no capacity for storage

As the Washington Post reports, two reservoirs on the Tule and Kaweah rivers are full, so they can't take on any more water to prevent flooding downstream.  One city, Visalia in the San Joaquin Valley might suffer flooding as soon as this week as water is released from behind the dam on the Kaweah river.

Those two reservoirs mentioned above are relatively small.  The risk of flooding increases when some larger reservoirs fill up. 

A USGS site in the Sierra Nevada mountains '
of California overwhelmed with snow recently. 

Another problem is the scale of the snow and the runoff this spring. It'll take a lot of time to melt literally dozens of feet of snow. Which means high water flowing down from the mountains will last many weeks.

The state has many aging levees that have not been tested by weather like this in years, or even decades. It's one thing to rely on the levees to hold back water for a few days. The pressure of flooding lasting many weeks might be too much for the levees to bear. 

Of course, levees tend to be in worse shape and the most neglected in low income communities and areas without a thriving agricultural industry. Typical story of the haves and have nots. 

SACRAMENTO DANGER

A worst case scenario - pretty unlikely at this point but still in the realm of possibility - is a huge flood in and around Sacramento, California's capital.

As Dan Walters wrote in CalMatters.org earlier this month, Sacramento is at the juncture of two pretty big rivers, the Sacramento and the American. 

Walters explained that a bypass channel protects the city from the Sacramento River, as long as levees along the channel hold nicely. 

But, the American River is a bigger threat. There's a flood control dam upstream from Sacramento called the Folsom Dam/Folsom Lake.  It can store water and ensure moderate stream flows in Sacramento in ho-hum water years. 

However, this year, we'll see a bigger snow melt surge over the next weeks and months coming down from the Sierra Nevada range. Folsom Lake could well be too small to deal with such a long, sustained snowmelt flood.

The winter rains and snows in California have seriously dented, if not eliminated drought in much of the state. That, of course, is a good thing. But, as always, there's a downside. 

As Walters reported: "'I hope I'm wrong, but I'm afraid people celebrating the great snows in the Sierra Nevada are seriously underestimating the risk of spring flooding in California, including reservoir operators and state and federal managers,' Peter Gleick, one of the state's foremost experts on water, tweeted."

Warm atmospheric rivers - ribbons of intense moisture in the air that wring out tons of rain, hit California at mid-month. That melted a lot of the snow in the some of the foothills, mostly at elevations between 1,500 and 3,000 feet above sea level.

 Even though some rain came down in rather high elevations of the Sierra Nevada, those warm storms might have done more harm than good,

Winter rains actually don't melt much snow, but they do soak into the snowpack, making the amount of water primed to run off as melting in the spring that much more intense. 

As Daniel Swain, a climate scientist at UCLA's Institute of the Environment and Sustainability, told The Fresno Bee, California is now in uncharted territory.

Swain continued explaining to The Fresno Bee:

"'There is so much water stored in the southern Sierra snowpack, at or above record levels,' Swain told The Bee. 'And we haven't had a climate as warm as we currently do with a snowpack this large.' An early season heat wave, which has become a more occurred e in recent years 'could happen in the spring and could cause a lot of this snow to melt quickly.'"

Part of the reason why California had been in such an extensive drought in recent years is intense spring heat waves prematurely melted what little snowpack had accumulated in the Sierra.

So what happens if it's suddenly really hot and sunny in April and May this year?  Swain sounds nervous, as I would be.  

As in almost every other place, if temperatures are moderate in April and May, the snow melt in California would be gradual enough to prevent severe flooding. So, it's really a tossup as to whether the serious flooding the state has experienced will last into the beginning to the so-called "dry" season in May. 

Of course, California is also famous for its wildfires. The extreme snows and rains could make the fire season go either way. 

Above 6,000 feet, especially if the snow melt is gradual, it'll stay wet in the high spots through the bulk of the fire season. That would suppress high elevation fires, Swain told the Fresno Bee. 

The problem would come at lower elevations. All that rain is making plants, underbrush and such to grow exuberantly. If it's a hot, windy summer in California, all that new brush will dry out. So will the stuff that blew down in the high winds this winter. That could create a nasty fire season. 

It seems nowadays, any kind of weather creates a new crisis in California. 

 

Just Like That, Two Big March Vermont Snowstorms Have Increased Spring Flood Threat

Snow-laden trees and deep snow this week around
St. Albans, Vermont.  A now much deeper snowpack
has somewhat increased the risk of spring flooding.

 Lo and behold, after pretty much an entire winter in which the snow pack in Vermont was well below average, the snow is now deep just as we're on the cusp of spring. 

That extra snow increases the flood threat in the coming weeks, but something like that is fortunately far from guaranteed.  It's still worth keeping an eye out on, though.  

The National Weather Service in South Burlington releases a winter and spring flood potential statement every other Thursday. Conveniently, the latest came just after the much larger of the two March snowstorms ended. 

Thursday's statement says the flood potential in northern and central Vermont is about normal. But it cautioned we'll have to start carefully watching weather patterns starting in about a week and a half. 

The amount of snow on the ground across Vermont - and the water in it - is now in many places above normal for this time of year.

The snow depth just below summit level on Mount Mansfield was  62 inches on Monday, just slightly below normal By Wednesday afternoon, the snow depth on the mountain had ballooned to 90 inches, which is roughly 15 inches above normal for the date.  

The snow water equivalent - the amount of "rain" available from the water in the snow and ice covering the ground is about 1.5 to 4 inches in the valleys, and four to eight inches at elevations between 1,500 and 2,500 feet.  I saw one measurement from Shrewsbury that showed 5.03 inches of "rain" locked up in the snowpack there. 

This week's snowstorm added one to three inches of snow water equivalent to the snowpack. Isolated areas in the high country of far southern Vermont added four inches of "rain" to the snow pack.

The snow cover in January and the first half of February was practically non-existent in Vermont. But much of the snow that has fallen since mid-February is still on the ground despite generally above average temperatures. That is in part because most of the above average temperatures have happened at night. Daytime readings have been closer to normal. So that limited much thawing so far. 

WHAT'S COMING

If you get the wrong kind of weather, that's a recipe for flooding.  The "wrong" weather is a sudden shift to much above normal temperatures combined with heavy rainfall.  

Jackson the Weather Dog is dwarfed by the big snow banks
he's inspecting for spring flood potential around
our house in St. Albans, Vermont. 

In the short term, that won't be a problem. Some light snow Thursday added a little tiny bit of potential flood water to the snow. 

Light rain causes some snow melt on Friday.  I noticed brooks and rivers rose somewhat with the thawing and rain, but nothing came close to flooding. And there's plenty of snow left to melt. 

A quick blast of chilly air will dump another dusting of snow in the valleys and a few inches in the central and northern Green Mountains. Again, just another small installment into the spring run-off potential from the mountains. 

Most of next week will have great sugaring weather, with highs near 40 and lows in the 20s. Great sugaring weather is also great flood prevention weather. A little snow melts each day, then things freeze up each night, so runoff isn't a problem.

Beyond that, it's beginning to look like we'll have a turn toward milder weather. The first shot at any spring flooding this year might be next weekend,  depending on the strength and path of the next storm system.  That storm is nearly a week away, so we don't know if it will be a warm, heavy rain, which would cause problem, or something more along the lines of what we had Friday, which wasn't at all scary.  

Even if the storm a week from now is warm and wet - again far from guaranteed - there will be plenty of snow left at mid-elevations and mountains to cause potential problems heading into April. Again, only if those spring rainstorms turn out to be hefty and drenching. 

Lake Champlain's lake level later this spring has gotten potentially more interesting, too. The lake level is around 96.4 feet, which is just slightly higher than normal for this time of year. 

Now, a lot of water has the potential to enter the lake from the surrounding countryside and mountains.  Especially if we have a lot of rain between now and May. 

Flood stage on the lake is 100 feet. I think we have a pretty good chance of achieving that. But minor flooding like that isn't a big problem. It's when we get up to 101 feet or so when trouble really begins. At this point, I don't think that will happen, but it is possible in a sort of low chance kind of way.

Whether we see any flooding this spring or not, I'm sure a lot of people will be relieved to see the snow banks around their homes gradually shrink and fade away under the warming rays of the sun. 

 

  

Snow Cover In Vermont Improves, Still Shy Of Normal In The Mountains

The snow pack in Vermont's mid and high elevations has
 gotten closer to normal due to recent storms, but is 
still below average for this time of year Pictured here
is Mount Mansfield this past Sunday. 

 Every winter and early spring, the National Weather Service office in South Burlington releases a spring flood outlook every other week. 

This biweekly statement also serves as a proxy to tell us how much available water there is in the snow cover to help soak the ground in the spring. 

The latest statement came out yesterday. To surely nobody's surprise, the snow cover and the water equivalent in that snow has gone up noticeably in the past couple of weeks. 

Snow cover and the amount of water in the snow is actually up to near normal for this time of year.  

Mid and higher elevations have not entirely made up the early season deficit and snow cover up there remains below normal.

Interestingly, the higher up you go, the more behind normal you get. As of February 2, the snow depth atop Mount Mansfield was 38 inches or 15 inches shy of normal. 

The amount of "rain" in the snow pack - how much water you'd get if you melted it - is about 2.5 to 4.5 inches at Vermont elevations between 1,000 an 2,500 feet above sea level.  That is definitely below normal.

Due to the relative lack of cold snaps this winter, river ice is also thinner than normal, which reduces the risk of ice jams and the floods those can cause. 

The snow pack, especially in the mountains, will continue to slowly build at least for the next week or two. It's hard to pick out whether we'll get any more big storms in the next couple of weeks. The weather pattern does favor frequent little storms, each of which would add slightly to the snow pack.

The first in that series of little storms is coming later this morning, in the form of a band of snow followed by a mini-thaw of a few hours this afternoon that won't be enough to melt much of the snow. 

New snowfall today will be a dusting to two inches. So no biggie.

 Odds favor near or below normal temperatures for the next couple of weeks, so a big, early snow-destroying thaw seems unlikely. 

So it's possible - but definitely not certain -  the snow pack, and the equivalent water in that snow, will reach closer to normal as we make our way through February. 

By the way, these biweekly flood outlooks are not foolproof predictions. They just follow what the trends are. For instance, if it were to suddenly warm up to way above freezing with heavy rain,  there would be a high risk of flooding due to the rain and snow melt. 

Conversely, if the snow pack managed to get way above normal so that there were tons of water waiting to be released, that wouldn't automatically result in spring flooding. If the spring melting is slow and gradual, we wouldn't really see any flooding to speak of.