As you might have already heard, the National Weather Service has issued a tornado watch for the southern four counties of Vermont, all but northern New Hampshire much of central New York and most of Massachusetts.
That means tornadoes are possible. If you are under this watch, continue doing what you're doing, but just have a reliable source of weather information next to you so you can hear any warnings come through.
If, on the off chance you get a tornado warning, march right down to the basement with your weather radio or weather source and stay put until you get the all clear. If no basement, an interior windowless room will do.
This isn't meant to be alarming. Just a precaution. Most people in the tornado watch area will not get a tornado warning. (A warning means a twister has been spotted or a potential one is on the radar screens).
So far at least, the forecast is playing out as expected. The northern third of Vermont has had some rain, and it's remaining pretty much overcast. And it looks like another batch of steadier rain is moving in, That is helping stabilize the atmosphere and limiting thunderstorms. There might be a strong thunderstorm or two up north coming up, but it won't be as extensive as further south.
Further south, there's a little sun, better dynamics and more shear, which is winds changing in direction and/or speed with height. That will allow some thunderstorms to spin, especially if any supercells form ahead of the main band of strong storms.
The tornado watch lasts until 10 p.m. tonight, but it might expire in Vermont a little sooner than that as activity shifts to the east late this evening.
By the way, and this is important, if you get a severe thunderstorm warning but not a tornado warning, still take that very seriously. The worst of these thunderstorms will be capable of causing as much straight line wind damage as a tornado would. And the straight line winds with these storms will be more widespread than any tornadoes, if any twisters form at all.
There will almost definitely be some severe thunderstorms scattered around southern Vermont in the next several hours. Tornado chances are iffier, but as you can tell, still possible.
UPDATE: 11:30 a.m.
 |
| The threat of severe storms has been pushed north to encompass most of Vermont. Rotating supercells are possible in the yellow and orange zones. There's still a small risk of brief tornadoes in this area, but the main danger will be strong damaging wind gusts and microbursts |
A warm front with the approaching storm that will cause the rough weather is moving further north than expected, and that is helping push the instability needed for the storms further north.
As earlier forecasts indicated, the greatest risk for severe storms is in southern Vermont.
However, that somewhat higher risk zone has been pushed north to a Middlebury to Bradford line.
South of this line, a few supercell thunderstorms could develop. They might rotate, which raises the risk, albeit small, of a tornado or two. Even if no tornadoes form, these scattered supercells, and also a subsequent likely line of storms could cause damaging wind gusts, microbursts and large hail.
A few computer models focus the most dangerous storms in Rutland and Windsor counties, but that certainly remains to be seen. Anyone in Vermont should pay attention to further forecasts and warnings.
PREVIOUS DISCUSSION
There's some real weather whiplash going on this week, as we've gone from snow last Friday and Saturday to a severe thunderstorm risk - at least for some of us - today.
At least it's warmer, right?
NOAA's Storm Prediction Center has that risk of severe storms today in a good chunk of the Northeast, especially in the southern two thirds of New York, much of Pennsylvania and New Jersey and much of southern and central New England, including the southern half of Vermont.
Any of these areas could get damaging winds, hail, and perhaps a spin up tornado. Of most concern is a narrow area encompassing central New York, western Massachusetts, the two southernmost counties of Vermont and the southwestern corner of New Hampshire.
At least that's the way things were looking early this morning in advance of this thing.
A storm with a center that was pretty close to Detroit early this morning will move probably right across far northern Vermont and New Hampshire this afternoon and evening.
That will put especially areas from about Montpelier south into the warm, humid air ahead of the storm. Skies seem like the might partially clear for a time during the early and mid afternoon, perhaps from about Rutland and White River south.
Especially in those areas, some muggy, summerish air will come in ahead of the storm's approaching cold front.
Forecasters are expecting short lines or clusters of thunderstorms to form ahead of this cold front and move east through New York and into central and southern New England this afternoon and evening.
The main threat from today's storms will be strong, damaging straight line winds from some of these storms. Large, damaging hail is also possible, especially in the zone of most concern I mentioned.
It's even possible a few rotating supercell thunderstorms could sprout ahead of the cold front today. That means there's a small, but certainly non-zero chance of a brief tornado or two in far southern Vermont, western Massachusetts, and especially in central New York and the Hudson Valley from Albany to just north of New York City.
 |
| Areas highlighted have a slight, but not zero chance of a brief tornado or two today, says NOAA's Storm Prediction Center |
In any event, any strong to severe thunderstorm can be dangerous. Remember, straight line winds can be a destructive as tornadoes.
If you are in areas today and this evening that are under a threat for severe storms, have a weather radio handy, or some reliable source to receive severe weather warnings.
As we always advise, stay indoors and away from windows during a severe thunderstorm or tornado warning. In fact, in the unlikely but possible chance that you fall under a tornado warning, it would probably be best for you to hide in the basement until the danger has passed.
Up in northern Vermont, where I am, things will be calmer than points south. But in the north, there could be some briefly heavy rains in spots, and a few rumbles of thunder from some potential embedded non-severe thunderstorms.
I'm also sure as more data comes in this morning, forecasts for the severe weather risk will be adjusted. So whatever you see here this morning is not absolutely set in stone.
Things will clear out today to give us a pretty nice weekend. It will be huge contrast to last weekend, when there was snow and strong, gusty cold winds.
Instead, this weekend will feature light winds, a fair amount of sun, though with some clouds, and seasonably mild temperatures.
The only drawback to this weekend's weather will be the lack of wind. Normally, that's fine, but with the warmer weather, black fly season is here with a vengeance, and they are really bad this year. With no wind to blow them away from us, expect to get attacked visciously by these little buggers if you go outside Saturday and Sunday.
No comments:
Post a Comment