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| There's a level two out of five threat of severe thunderstorms in yellow shading. That includes southern Vermont, eastern New York and southwest New England. There's an even greater chance of severe storms in parts of the Upper Midwest today. |
A few areas in the Green Mountain State could see strong to damaging wind gusts in a few of the storms that could form today.
The best chances of a severe storm are south of a line from Saranac Lake, New York to Lebanon, New Hampshire, the National Weather Service office in South Burlington tells us.
That's basically along and south of Route 4 with the risk getting into the southern Champlain Valley as well. The risk in this area is level 2 out of 5 point scale.
All of the rest of Vermont except maybe the extreme northeast tip has a quite low, but not zero chance of an isolated thunderstorms with potentially damaging winds.
The culprit is a cluster of thunderstorms in the central and eastern Great Lakes early this morning. They're the leftovers of severe weather that sent a few tornadoes swirling through northern Iowa, southern Minnesota and Wisconsin yesterday.
During the heat of the day, as these storms approach us in northern New England, they might strengthen again. Not nearly enough to give us a round of tornadoes like in the Midwest, but give us the risk of strong winds.
A "NOWCAST" DAY
The National Weather Service is calling this a "nowcast day." There are so many moving parts that have to line up, or not line up to produce our thunderstorms. And determine how rambunctious they'll get. And where they'll hit.
We won't really know for sure how this is going until things start to bubble this afternoon. Especially going to spend the day outside, you'll want to have a way to hear special weather statements, forecast updates and possibly severe thunderstorms watches or warnings.
Remember, a watch means maybe. Think of it is as your mother calmly calling you in, using your nickname. A warning means a severe thunderstorm is coming. That's your mother, angry, urgent, using your full name to get yourself inside. "JOHN MATTHEW SUTKOSKI, GET YOUR ASS IN THE HOUSE NOW OR YOU'LL REALLY HAVE SOMETHING TO BE SORRY FOR!!!!"
Ahem.
Anyway. back to those factors that will go into today's storms.
One factor is sunshine. Sun heats the atmosphere, to be Captain Obvious here, and that make the air more unstable and leaves more energy for vigorous thunderstorms. We don't know exactly how much clearing we'll get so we'll have to wait and see. As of 8 a.m. today, the clouds were pretty thick across Vermont. It's a wait and see game to determine whether it will clear out at all.
Early guesses are the best shot of any clearing later this morning and afternoon is along and south of Route 4, which is one reason why the better chance of strong storms is down in that neck of the woods.
Also, high clouds blowing off the existing storms early this morning in the Great Lakes could race eastward, covering our neck of the woods and maybe suppressing the chances of strong storms. That's another wait and see situation right there.
Another factor is timing. The models try to develop showers and storms in northern New York early this afternoon. Some of those models bring the shower and storms into Vermont early to mid-afternoon. If that happens, they won't have as much time to develop and won't necessarily be as strong.
Other models bring the storms in late this afternoon, when they're more likely to be stronger. To complicate things further, the storms might or might not come through in one line. There might be several short lines of storms in various places, or clusters of them, or even isolated ones here and there.
Upper level winds are stronger north. If the winds are stronger up above, storms have a better shot of bringing those strong winds down to the surface. So, things aren't lining up perfectly. The best instability is south, but the best winds for strong thunderstorms are north.
It still does look like upper level winds in southern Vermont are sufficiently strong to at least create seen risk of damaging thunderstorms.
Here's something else I have to throw in: We have a sort of east to west weather front draped over Vermont or at least nearby in extreme southern Quebec today. You really have to watch weather fronts that are oriented that way. Especially in the spring. You get surprises sometimes from these lazy, sneaky fronts making their fainting couch the Canadian border.
We'll see a large temperature contrast today in Vermont because of that front. Up along the Canadian border, forecast highs are around 60 degrees. That goes up to 70 by the time you get to Montpelier, low 70s in Rutland and upper 70s in Brattleboro.
The temperature contract could help strengthen storms. At least the ones in the warmer air to the south.
That front also makes it slightly possible we might get one or two storms to start rotating, maybe creating a sort of mini-supercell or two. I know we equate spinning storms with tornadoes. And there actually is a very low, but not zero chance of a brief spinup today. Even if a storm is spinning but does not produce a twister, it would tend to be more severe than one that is not spinning
Finally, you might have questions about flooding. Rivers are running sort of high. The ground is pretty squishy, especially where the frost hasn't entirely thawed from the soil yet. Northern Vermont in particular has gotten some rain in the past couple days.
That will have people asking about flooding. I think we're good in that regard. It's true that some of these storms - if they do come into the state - will pack some pretty torrential downpours. A couple of these downpours might even get a couple small streams out of their banks or erode the edged so some gravel roads. Especially since the soil is so soft this time of year.
The storms - again if they develop - will be moving right along, so torrential rain won't last long in any one place. Which really reduces the chances of flooding. In general, most of us would receive a safe half inch or so of rain today, give or take. Places that get really bullseyed by more than one storm could get up0 to an inch.
However, so far at least, it looks like we won't have any real problems with that. But the very low but not zero flooding risk is another reason to pay attention to today's "nowcast" weather updates.
REST OF THE WEEK
The unsettled, mild to warm weather will continue into the weekend, but we have big changes coming after that.
Making it seem like summer, showers and possible thunderstorms - most likely in the afternoons and evenings - are a good bet each day Wednesday through Friday. No word yet on whether any of those storms will be strong. It's another thing we'll need to wait for details on.
A strong cold front Sunday will knock us back down to early spring reality. Forecasts call for highs in the 40s by next Monday.
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