Big Midwest Severe Outbreak Underway; "Wrong Way" Cold Front To Protect Us In Vermont

The upper Midwest, especially the areas in 
red and orange, are in for a significant
severe weather outbreak today. Tornadoes,
some of them large, big hail, damaging winds
and flooding are all in play.

UPDATE 5 p.m.

NOAA's Storm Prediction Center has issued a Particularly Dangerous Situation, or PDS tornado warning for much of Minnesota.

A PDS tornado warning is pretty rare and means forecasters expect several strong to even extreme tornadoes that could have long tracks. 

As of 4:30 p.m. eastern time, several tornado warnings have already been issued in eastern South Dakota and a lot of damage has been initially reported in Sherman, northwest of Sioux Falls. 

I do think that at this point, locations south and west of Sioux Falls are in the clear, but it's going to be a horrible few hours in Minnesota and far eastern North Dakota.

Meanwhile, here in Vermont, that "wrong way" cold front has the makings of creating some strange, but not dangerous weather in Vermont. 

Depending upon where the front is tomorrow afternoon, high temperatures in varying places in Vermont will be somewhere between the mid-60s to near 90.  The coolest readings would probably be in the far northern Champlain Valley and perhaps the Northeast Kingdom.

There's potential, too, for what are known as elevated thunderstorms Wednesday. The cool, stable air near the surface behind the front in Vermont would prevent thunderstorms from forming. But warm, humid air above the shallow cool air could support thunderstorms that form higher up.  Those, if they develop, could produce locally heavy rain and even a little hail. This is not guaranteed, but possible. More details tomorrow morning. 

PREVIOUS DISCUSSION 

What will probably be one of the biggest outbreaks of severe weather and tornadoes of the year is underway in the Upper Plains and Midwest, with today expected to be the worst of it.  Minnesota seems to be ground zero, but surrounding states are being pounded, too. 

This all will head east over the next couple of days, but a wrong way cold front looks like it will protect at least most of Vermont from this bad weather. We'll get more into Vermont and New England in a moment. 

First, out West. 

The good news is no known tornadoes developed in Nebraska and South Dakota last night from supercells that formed late in the day. The bad news is there were a few reports of hail five inches in diameter - about the size of a cantaloupe. That had to hurt! 

Since there were only a couple supercells last night in Nebraska, it was both humorous and scary to see easily more than 100 storm chasers clogging the roads near the storm for a view.

We saw several other reports of large hail and damaging winds in Nebraska, South Dakota and Minnesota yesterday.

Early this morning, another wave of severe thunderstorms was passing through Minnesota. This line has produced wind gusts as high as 84 mph and some large hail.  Unfortunately, this early morning stuff is just an appetizer. 

A well organized and strong for this time of year storm system should gather the right ingredients for a tornado outbreak, especially in western Minnesota, northeastern South Dakota and southeastern South Dakota.

Some of the tornadoes this afternoon and evening could be quite strong and long-lasting.  The larger towns in this area that is particularly under the gun are Fargo, North Dakota, Moorhead, Minnesota and Brookings and Watertown, South Dakota. 

Since this storm has a lot of moisture to work with, there's a real threat of flooding again in parts of already soggy eastern North Dakota and western Minnesota.

The National Weather Service office in Grand Forks, North Dakota, whose coverage area includes western Minnesota, is not playing games. You don't often see stern wording such as the following from NWS offices

"(There is) potential for damaging winds up to 80 mph, hail over 2 inches in diameter and tornadoes possibly significant.......This looks to be a particularly dangerous afternoon and evening for all modes of severe weather. People need to pay close attention to the weather and have a way to receive warnings. Make sure to go through  your severe weather action plan, especially for the lakes country of Minnesota. Have a shelter where you can go if dangerous weather approaches. Do not wait until it is too late to get your plan in place."

The severe weather will shift east tomorrow and Wednesday, though it won't be quite as intense as it is today. Which brings us to what's going on around where we live in Vermont. 

VERMONT IMPACTS

By Wednesday, a severe weather threat will
reach much of New York, but at this point
it looks like a "wrong way" cold front 
will prevent that risk from 
reaching into Vermont.

Sunday was about as perfect an early summer day as you can imagine in Vermont. Warm temperatures, blue skies, pretty puffy clouds, low humidity. It was the total package.

Today will be pretty good, too, though high clouds might dim the sun at times this afternoon.  Most valleys should get up to 80 degrees or so today. 

Then the weather in the Northeast gets interesting, but here in Vermont, very likely not dangerous. 

We've been talking about that "Wrong Way" cold front for a few days now. It's a back door cold front, coming at us from the northeast and east, rather than west the way cold fronts are "supposed" to act.

The wrong way cold front will probably sweep southwestward and make it down to southwestern Vermont and the southern Adirondacks by tomorrow afternoon.  

That will keep temperatures suppressed, ranging from the 60s in the Northeast Kingdom to the 70s for most of us. Far southwestern Vermont might get into the upper 80s ahead of the front.

It will get really interesting in southern New England, where some areas will see temperatures rise into the upper 80s, only to crash into the mid 60s within an hour or two as the front moves in from the east. 

Meanwhile, that severe weather from the Midwest will be moving our way.

It turns out that Wrong Way cold front might be a bit of a savior for most of Vermont. Warm, humid unstable air will be in place Wednesday west of that stalled wrong way front in western and central New York. That will support thunderstorms, some with damaging winds and large hail in that area.

However, the air behind the wrong way front, where most of Vermont will stay, will be quite stable, at least in the lower levels of the atmosphere. As the thunderstorms in New York and Ontario encounter the stable air here, they'll just change into regular old showers and maybe a rumble of thunder. 

We will have to watch weather the wrong way front wiggles back toward the northeast a bit on Wednesday. If that happen, southwestern Vermont might be in play after all for a few strong storms. We shall see!

After that, we're in for a spell of pretty average early June weather for the rest of the week and next weekend.