Saturday Storms Did Pop In A Few Areas: More Vermont Severe Weather Today

A volatile looking sky over St. Albans, Vermont Saturday
evening as severe thunderstorms passed by well north
and south of town. 

 Saturday's storm development, almost surprisingly, developed about as expected in Vermont. That was just round one.  Round 2 of severe weather is still in the forecast today. 

A derecho developed around Michigan early Saturday then roared through the metropolitan areas of Toronto, Ottawa, Montreal and Quebec City.  I saw one estimate that indicated that since this hit so many urban areas, the line of storms affected half of Canada's population. 

Damage was especially intense in and around Toronto. 

The derecho passed north of Vermont, but was a catalyst to break a cap, which was a warm layer of air high above. 

This allowed thunderstorms to develop rapidly in northern New York and Vermont and race across the area, mostly along and north of Route 2.  As expected, the intense storms were hit and miss, and most people did not have anything too intense.

Even so, winds of at least 55 mph downed trees in Williston. Quite a bit of tree damage was reported around Eden, too. Another severe storm skirted the International Border between Alburgh and Franklin, dumping hail up to the size of half dollars and causing additional tree damage.

Another wave of thunderstorms - not severe but with plenty of lightning - zipped across northern Vermont late last night. That storm caused a power outage lasting two and a half hours at my place in St. Albans. 

It'll be quiet this morning and then we have another risk of those strong to severe storms. The National Weather Service in South Burlington is thinking today's storms will be a little easier to forecast compared to yesterday.

Until the storms started developing Saturday, there were questions as to whether there would be enough of a trigger to launch those storms. Turned out there was, at least sort of.

Today, we know we'll have the trigger in the form of an approaching cold front and something called a pre-frontal trough out ahead of it. A pre-frontal trough is very common with summer cold fronts. It's just a pocket of lower pressure ahead of the cold front that causes a bit of a wind shift. That's an easy trigger for storms. 

So we'll end up with clusters of storms along this pre-frontral trough this afternoon, and probably with the cold front itself. Usually the pre-frontal thunderstorms are the stronger ones. 

This will be a west to east affair, starting around  1 or 2 p.m.- ish in New York and proceeding across Vermont from mid-afternoon into the early evening. 

This means the activity will come through after the University of Vermont's outdoor graduation ceremony today. But if you're going, drink plenty of water and bring sunscreen. It's very warm and quite humid out there 

As of early this morning, Vermont remains in a slight risk zone for severe storms, a level 2 of 5 alert. This means the biggest threat from the storms is, as usual, strong gusty winds. Most people won't see damage, but there will be pockets in which the wind will be strong enough to toss down trees and power lines once again. There could be some isolated areas of large hail, the size of quarters or half dollars again. 

Once again, there's a very, very remote chance of a quick spin up tornado, but that's quite unlikely. There's a slightly greater chance of a quick twister in western Maine. 

It'll turn noticeably cooler overnight tonight, and the first half of the week is still looking nice, with comfortable afternoon temperatures in the 60s to around 70