Tornado And Severe Weather Threat Still Big Risk In South

The question of the weekend in the Deep South is where there
be more of these types of highly visible but also highly
destructive tornadoes, or.....

Meteorologists around the nation, but especially in the Deep South are still watching what could be a terrible severe weather outbreak unfold this weekend.

Not to be glib in a situation like this, but it's an April classic, at least as the overall weather set up is.

A strong - and strengthening storm will move from the Plains to the Great Lakes Sunday and Monday.  There's going to be another snowstorm on its northwest flank from the central Plains up into Wisconsin and Upper Michigan.

Strong, destructive winds and shoreline flooding are forecast for most of the Great Lakes.

But the real, most worrisome situation is the threat for tornadoes, some maybe long lasting and strong, especially Sunday. As readers of this blog thingy know, forecasters have been watching this situation for days now, and there are no signs so far that anybody can rest easy.

The first hint of trouble came Friday with a swarm of supercell thunderstorms in western Texas that produced some gigantic hail stones, as loud and enthusiastic storm chaser Reed Timmer discovered.

The trouble will begin to really blossom today. as most of Texas and a large chunk of Oklahoma fall under a severe storm threat. Tornadoes and destructive straight line winds are real threats today, but large hail is once again the predominant hazard today and tonight in this area.

The Sunday threat covers a huge area from eastern Texas to the Carolinas and from the Gulf Coast to the Ohio River.  The main bullseye for the worst of it continues to look like it will be Louisiana, Alabama and Mississippi, at least as things stand now.

The question is not whether severe weather develops, it's what form it will take. The worst way it could develop if a bunch of rotating supercells form, with each one being on its own, not part of any squall lines.

If that happens, you get these wide, long lasting and intense tornadoes that cause the most extreme damage, and are the most life-threatening since they are so strong.

....or something like this not quite as strong, but still dangerous
and also hard to see coming rain-wrapped spinup tornadoes 

Things could instead develop into messy lines and cluster of thunderstorms. That's still really bad, because there would be embedded tornadoes and very serious straight line winds.

But most of the time, the tornadoes in this scenario, while still extremely dangerous, are not the high end super bad ones you get with those more isolated supercells I talked about above.

The tornadoes in these "messy" clusters have their own hazard, however. These are usually hidden within curtains of rain. Human nature sometimes prompts people to look for the tornado that's threatening them before taking shelter. Usually, you can't see this type of tornado coming.

Though there are guesses, I don't think anyone really knows how this will develop until it gets going. There will probably be those messy lines and clusters of storms, and discreet, big tornado ones,  but nobody is sure which style will predominate.

Some of the same areas most at risk for tornadoes and damaging winds also have a substantial flood risk.  At last check, most of Tenneessee and the northern halves of Mississippi, Alabama and Georgia in particular are under the gun for heavy downpours and flash floods on Sunday.

It's already been a tremendously wet year in these areas and the expected three to six inches of rain Sunday and Sunday night will only trigger more flooding.

VERMONT IMPACTS

Here in Vermont, there will certainly be no tornadoes, but the storm will give us a few problems, albeit minor compared to what will go on in the South.

The storm will bring a quick slug of fairly heavy rain through on Monday. The National Weather Service is foreasting perhaps a half inch to an inch of rain.

That doesn't make me too frightened about any flooding, but we'll have to watch the Northeast Kingdom.  The mid elevations and mountains got quite a bit of snow from that last storm Thursday night and Friday. Averill, way up in the northeast corner of the state, got a foot of snow out of that one.

The lingering snow, and snow from previous storms on the mountains in the Northeast Kingdom, will do a lot of melting amid the rains coming up Monday, so there is the risk of some high water. They'll need to watch the flood prone Passumpsic River for this one.

The big story in and near Vermont with this one will be the wind. There will be gusts over 40 mph ahead of the cold front Monday morning and early afternoon.  Once the cold front passes, the winds will really crank, especially in northern New York, the northern Champlain Valley, and I think eastern slopes of the Green Mountains.

Winds could easily be strong enough to damage trees and power lines Monday, so we should keep that in mind.