For much of the day, it looked like western Maine would suffer the worst of this outbreak. But it hasn't warmed up as much ax forecast in the main Maine risk zone, so to speak. At 4 p.m., Rangeley, Maine was only 73 degrees.
Temperatures in the 80s would have helped make storms more powerful. Maine might still get nailed, but the lower temperatures raise questions about the severe threat there.
Here in Vermont, it's also a bit cooler than forecast, but still much warmer than northwestern Maine. As of 5 p.m., it was well into the 80s, with a couple spots close to 90 degrees. The dew point had risen to near 70 across the state.
Those are super juicy conditions for storms.
The winds are also veering with height, and are pretty strong higher up. Here down on the ground, winds are from the southwest. Higher up, the winds are westerly. Go up even further to jet stream level, the winds are northwesterly.
That's a great set up for severe weather.
With all these ingredients for storms, we just need the trigger.
The National Weather Service in South Burlington said that so far, the smoke has tamped down attempts at thunderstorms. But the approaching cold front, and a so-called pre-frontal trough ahead of it, would overcome the smoke and fire up some storms.
At least that's what the thinking was as of late this afternoon.
At this point, as of nearly 6 p.m., it's still unclear whether this will develop into the nasty severe outbreak that has been forecasted since yesterday, or a total forecast bust/false alarm, or somewhere in between.
There were storms starting to fire in southern and central Quebec. There was a nasty batch of storms well north of Ottawa. We'll see if they hold together, as they were heading in our general direction.
I'd keep planning on a severe outbreak if I were you. The ingredients are still all there. We're just waiting for the proper triggers. Even if those triggers never fire, what have you lost by bracing yourself for the possibility of nasty storms.
As of 6 p.m., meteorologists much smarter than me were still insisting the triggers will fire tonight. In a Facebook post, the National Weather Service in South Burlington said confidence in severe weather tonight "continues to increase"
The NWS also said the wildfire smoke would have little, if any effect on the storms. It's just a matter of how well the atmosphere triggers work tonight.
NOAA's Storm Prediction Center is more nuanced for this evenings outlook. Wildfire smoke and a general cloudiness might be inhibiting storms. As of 7 p.m., they were still on the fence on whether to issue a severe storm watch.
Still, if storms can overcome these factors, severe storms will erupt.
We've still got the risk of destructive straight line winds, maybe a a couple of tornadoes. Somewhere in northern New England, a tornado might turn out to be strong. There's also the risk of large hail, local flash floods and continuous lightning.
Not everybody will see those dire weather conditions. But a few places might. From now until about 3 a.m., you'll need a way to receive storm or tornado warnings, just in case. Don't put your phone on do not disturb.
It's also important to note it's impossible to tell who will receive a severe storm and who will avoid them in advance. We won't know until just before the storms hit.
READING THE TEA LEAVES
Like every meteorologist and weather geek around, I've been constantly looking at satellite images and weather radar, and other data to see what's going on.
Things change fast with these severe weather episodes, but here's a snapshot at what we see shortly before 6 p.m.
A patch of clouds over northern Vermont late this afternoon was preventing storms from firing up. It was expected that we wouldn't see much of anything during the afternoon, so this part was expected.
It had gotten interesting just north of the border, though. Just north of the border was a narrow line of roiling clouds, some of which were developing into thunderstorms. A
At 5:19 p.m. today, one storm on that line prompted the first severe thunderstorm warning of the day, covering the extreme northeast tip of Vermont. Other thunderstorms were trying to develop further west along that line of clouds, but they were struggling.
There's sort of a temperature boundary between the relatively cool air in northwest Maine and the warmer, more humid air in Vermont. So I'm suspecting the Northeast Kingdom will see thunderstorms start fairly early this evening, as thunderstorms like to form along boundaries.
Speaking of boundaries, there's a pre-frontal trough south of the main cold front. Pre-frontal troughs are common in severe weather outbreak. They are a line of disturbed weather usually a few dozen miles ahead of the actual cold front.
The pre-frontal trough was encouraging thunderstorms far to the northwest of Montreal. They're embedded in wildfire smoke, so we're unsure if the smoke will interfere with further development or not.
In any event, the main show happens after 8 a.m. and continues to around 2 or 3 in the morning. If the forecast is correct, waves of storms will move down from Quebec into northeast New York, northern Vermont, northen New Hampshire and northwest Maine.
Again, if the storms develop, they'll be a mix of supercells and short lines of intense storms Those supercells are the prime suspects for forming a couple tornadoes tonight. Very few people will actually be affected by any tornadoes. But still, oe or two of them could still be strong.
The bigger danger is still straight line winds. The worst storms could have wind gusts of over 75 mph. If one of those comes through where you live, you'll see a lot of damage.
This isn't to say everybody gets severe weather. Some of the storms will indeed be severe, even intense. Other areas in the higher risks zones will wake up tomorrow morning wondering what all the fuss was about.
The storms should still weaken as they head toward southern Vermont after midnight.
WHAT TO DO
The first and most important thing to do is have at least one way to receive severe storm warnings all night. Fully charge your phone, leave it on your nightstand and have it set to blare if a severe storm or tornado warning goes up for your area.
You'll need to act fast if you get a warning, especially if it's a tornado warning. Have sturdy shoes next to your bed that you can slip on quickly. Also a flash light or better yet a head lamp so your hands will be free.
Make sure you're able to scoop up any pets on the way to the basement.
Some of the severe thunderstorms, if they develop, might have winds equivalent to a tornado so head to the basement even if it's a severe storm warning instead of a tornado warning. If you don't have a basement go into a small interior windowless space like a bathroom or closet. Put as many walls between you and the outside that you can.
If you're still camping, get out of the woods now if not sooner. Any forested area will be really dangerous if an intense storm or tornado comes along.
Before the storms arrive, secure outdoor furniture and plants early this evening before the storms arrive. I'll be doing that as soon as I finish this post.
Above all, don't work yourself up over this. It is a bigger severe threat than we're used to in northern New England. But for most of us, the worst we'll endure ia a noisy night with lightning, loud thunder, gusty winds and torrential rains in may spots.
An unlucky minority of us in the North Country unfortunately face real danger and likely property damage if the storms develop as meteorologists were anticipating as of 6 p.m.
Just take your precautions this evening and stay weather aware overnight

No comments:
Post a Comment