September Was Among Vermont's Hottest, And Among A Slew Of Recent Hottest Septembers

One of the many gorgeous days Vermont had in September,
2024. This is a shot of Georgia, Vermont on September 19.
Subjectively, it was just about the most pleasant 
September I can remember, but also one of the warmest.

Another September, another September that was among Vermont's warmest on record.

The mean temperature - at least as measured in Burlington, worked out to 65.6 degrees, the fourth warmest on record in data dating back to the 1880s. 

This means that the seven Septembers just in the past decade are in the top warmest on record in Burlington.

There are ties, accounting for the "bad" math there.  Number 5 warmest is a tie between 2023 and 1961, number 3 is a tie between 2016 and 2017).

That's quite a signal for climate change, isn't it?

This September, though was different than the slew of very warm Septembers in recent years. 

Those Septembers in the past decade or so have featured some extremes, such as torrid, sometimes record-breaking early month heat waves, uncomfortably oppressive nights, and a few severe thunderstorms and torrential rains.

By contrast, September, 2024 was remarkably pleasant by comparison. The hottest it got in Burlington all month was a relatively tame 86 degrees on three days, and the warmest night got down to a fairly reasonable 63 degrees. 

It also appears we tied with last year for the warmest low for the month of September. The chilliest night in Burlington only got down to 45 degrees.  For comparison, the coldest it has ever gotten in Burlington in September is 25 degrees. 

In one respect, we actually beat out last year for mild nights. In September, 2023, six nights got into the 40s. This year, there were only four such nights.

It's so out of whack that when it finally gets chilly, as it inevitably will there will be no frost or freeze warnings for colder areas of Vermont like the Northeast Kingdom. That's because in most years, those warnings are unnecessary as the growing season is considered over by now. They should have already had garden killing frosts by now.  Not this year!

Looking elsewhere in the state, climate sites in Montpelier, St. Johnsbury, Rutland and other places ran about two or three degrees warmer than  normal, just as Burlington did with its departure of 2.9 degrees above normal.

Remember this is the "new normal" which is the average of the 30 years ending 2020. Those three decades were decidedly warmer than the 20th century average. Had this year's version of September happened in the 1980s, it would have been something like a whopping six degrees on the warm side compared to what was then "normal."  

Another sunny, September, 2024 day. This was September 6
as viewed from near the summit of Mount Mansfield. 

In Burlington 2.68 inches of rain fell, which is about an  inch below normal. By my calculation, it was the 49th driest September out of the past 140 years. 

There were only five days with measurable rainfall in Burlington during September, which is remarkably small 

Also, what rainfall we did get mostly fell on two relatively brief occasions, each lasting about two days. 

Those two rain storms, and some showers on September 1, were very well behaved, causing more harm than good, as both tempered developing dry conditions. 

Most of the rest of the month featured sunny days, even if the majority of them started with early morning fog, which quickly burned off.

I have to say this was one - subjectively - of the most pleasant weather Septembers in my memory. Unlike so many other areas of the United States and world, Vermont enjoyed a no drama September. A welcome change from the weather violence we have endured from time to time in the past couple years. 

The fact that September was that  warm means that so far, 2024 is the hottest year on record. Whether that will hold for the entire year depends on whether we take a sharp turn toward colder than normal weather in the final three months of the year. 

Long range forecast are always iffy. But in general, if NOAA is right, the remaining three months of 2024 should be mostly warmer than average. We shall see if they're right.

In the somewhat shorter term, temperature and rainfall predictions are running close to normal through mid-October. 

The new month is starting off where September left off. Today through Friday should be generally sunny and warmer than average. Tomorrow will be an exception, with a risk of showers, a fair amount of clouds and temperatures merely near normal with highs in the 60s.