The Return Of A Vermont Summer, Smoke, And Slight Risk Of Flood Issues

Another hazy, smoky sunset over St. Albans, Vermont
Friday evening.

 It got up to 87 degrees in Burlington Friday, which is not exactly a remarkable temperature for early August. 

Still, it was the warmest day since July 15, signaling at least a temporary shift away from the relatively cool conditions we've had for a good month now.  

Your air conditioner is probably going to come in handy for the next week or so.  

Unfortunately, another familiar aspect of this summer returned Friday - wildfire smoke.  We knew this would be an occasional problem through into the fall, so there you go. 

On top of that, there is a minimal, but definitely not zero risk of flash flooding here and there on perhaps a couple days going forward.  That's bad news, too, since there's been damaging floods already in Vermont this summer. 

The good news is that the chances of any flash flooding look pretty small this week. And if the flooding does occur, it will probably be pretty isolated, and not widespread, fingers crossed. 

First off, the warmth:

The Bermuda High, that perennial summertime heat pump, had been mostly AWOL for the past few weeks, but it has now reasserted itself. We have decent shots of hitting 90 degrees in parts of Vermont over the upcoming week, depending on how cloudy the afternoons get.  It hasn't been 90 degrees in Burlington, Vermont since June 29. so this will be a switch.

Friday was also the last day for awhile in which humidity was pretty comfortable. That old Bermuda High is pumping plenty of moisture up from the tropics.  Already, early this morning, the air felt a lot heavier and stuffy here in St. Albans, Vermont than it did last evening, when I lazily lingered out on my back deck.

It will be muggy all week, and nights will be stuffy for sleeping. This state of affairs looks like it will go on at least until Friday. 

A cold front looks like it might flush out the oppressive air by around then.

All that tropical humidity means the air is set up for downpours and thunderstorms. All you need is a trigger to set them off. 

One such trigger arrives this afternoon, in the form of what  I suppose you could call a "cold front" from Quebec and Ontario. It's not really bringing any cooler air, or lower humidity. But it does add a bit of lift to the air and a slight wind shift.  

That'll be enough to trigger some showers and storms, especially this afternoon and evening, and especially along and north of Route 2. It'll all be hit or miss. A lucky few will get a good blast of a downpour, many others will get nothing at all, except perhaps a view of a dark cloud or two passing by to the south or north. 

The "cold front" such as it is, will just sort of fade away over central New England tomorrow. The remains of the boundary, and the usual updrafts around the Adirondacks, Green Mountains and White Mountains, should be enough to set off another round of hit and miss showers and storms Sunday afternoon and evening. 

Where they form and die is an open question.  Once again, many, if not most of us, will see no rain out of this, or very little. A few spots, especially in the mountains, will get a really socking from heavy downpours.  

Whichever storms do form Sunday probably won't move very fast, and with all the wet air around, they'll be able to produce a lot of rain in a short time.  That's where the risk of flash flooding comes in. NOAA's Weather Prediction Center has us in a marginal risk zone for flash flooding on Sunday.

That's the lowest of five alert levels and means there could, maybe be an isolated spot or two with flash flood problems.  If I had to guess where this might happen, if at all, I'd say the southern Green Mountains. 

There are chances for additional torrential downpours Wednesday into Friday, but it's too soon to figure out how widespread and heavy they might turn out to be.

As for the wildfire smoke, there's no fires to speak of in the Caribbean and western Atlantic Ocean, of course so that air coming at us from there is pretty clean.

But dirtier, smokier air can get entrained in this southwest air flow over us, so you will see varying levels of haze over the next week and beyond. So far, it doesn't look like it will be anything extreme over New England, so air quality will be OK.

At least we don't have choking smoke like cities in the western half of the U.S. are experiencing. Air quality alerts are rampant out there, so I'm sure there will be health effects. By the way, I've read that air pollution makes Covid worse.

Sigh.