Odd Vermont September Heat Begins Today, But Really Gets Going Midweek

A hot muggy evening in Vermont, September 2020. A hot
spell is due this week, continuing a trend in recent years
of very warm Septembers in the Green Mountain State.

 The last time the temperature in  Burlington, Vermont got passed 83 degrees was way back on July 28.  As mentioned in a previous post, it was the coolest August maximum since 1927. 

Well, it's payback time. 

It could get as warm as 85 degree today, and then, at least in the valleys, it will probably be in the upper 80s to around 90 each day Monday through Thursday. Quite a stretch for a Vermont September if it pans out.

Although this won't be the worst heat wave ever, the National Weather Service in South Burlington notes two factors that will make this one a little tougher to take than you might expect.

For one, although we had our fair share of humid days in August. we haven't had a true hot day since July 28, when it was 91 degrees in Burlington. So, we'll have to re-acclimate to the hot weather. 

An even bigger deal is the fact that schools are open. Most Vermont schools are not air conditioned, so classrooms will get pretty hot.  Teachers and faculty will have to watch kids closely for signs of heat exhaustion or dehydration.

Vermonters accustomed to schools closing during winter storms. I wonder if some schools will have to shut down because of the heat. 

That's possible, because nights will be quite stuffy during this hot spell as well. Which means room temperatures won't drop much at night. The heat in those school buildings, many of them old, will build up.

One thing that could keep temperatures from really getting out of control is the wet summer we had. The wet ground will add humidity to the air, which would knock back temperatures a bit. Of course, that doesn't help any of us at all, because the extra humidity will just make things feel worse. 

Although there might be a few daily record highs in Vermont between Monday and Thursday, this won't be an all-time record breaker. 

With climate change, Septembers, like pretty much all months, has gotten hotter than they used to be.  

The long time record hottest temperature in Burlington for September was 95 degrees set in 1931. That is, until 2002, when it somehow rocketed up to 98 degrees on September 9 that year. 

Strong 90 degree heat waves also set record highs in September in 2010, 2015, 2017 and 2018 so the suite of daily record highs in September have changed hugely over the past two decades.

I don't know how this entire September will pan out, but there's been a big trend for hot Septembers.  Five of the top six hottest Septembers in Burlington have happened since 2015, and seven of the top ten happened since 2002.

Who knows whether this month will join that hot September list, but we're off to a rousing start.