Yesterday the newest 6-10 day and 8-14 day Temperature Probabilities from the Climate Prediction Center were released. It should be no secret by now that fall temperatures/weather are my happy place, so I was excited to see if perhaps there was a hint of a more longer-lasting cooldown in the outlook.
Spoiler alert: There wasn’t. At least for a large portion of the country.
Graphic below for reference.
Viewing this outlook got me thinking: when was the last time we had a real, somewhat significant, widespread, below average “early fall” (the month of September)? I remember, as a child growing up in the 90s, that cool Septembers seemed to be the norm, especially where I grew up in the Northeast. So off I went to the model lab at weathermodels.com to consult the Prism Temperature Anomaly Analysis.
The answer? September 2006.
You can, of course, do your own research here by looking through the analysis, but what I found was, that from 1981 (when the analysis begins) to around 2000, below average Septembers were fairly common. This jives well with my childhood memories of sweaters on the first day of school and coats by month’s end. Around 2000, however, things changed. Above average temperatures for at least part of the country became common from year to year with, as I mentioned, 2006 being the last widespread, significantly cooler September. In 2015, significantly warmer Septembers (again, for at least part of the country) started becoming more common with 2019 showing rather anomalous warmth.
My point to this rather long preface is that warmer Septembers are becoming more and more common and this year certainly won’t be an exception.
After the passage of a rather weak front mid-week, a ridge will begin to build over the center of the country before becoming quite strong over the Northeast.
With this ridge in place, the only region experiencing a cooldown will be the Northwest, which will be under the influence of a trough. I’m going to be honest though, after the record-shattering summer they’ve had out there, I’m not going to begrudge them their cooler weather. Enjoy it, Northwest folks. You’ve earned it.
So with a trough digging into the west and squishing the ridge to the east, temperature anomalies of 10 to 20 degrees above average could be seen not only in the central US, but extending into the northeast and, more significantly, southeastern Canada as well.
Unfortunately, medium-range ensemble guidance doesn’t suggest a change to the pattern in the next 2 weeks or so, either. Of course, that can always change as uncertainties abound the further out into the future we forecast.
For you warmth-loving folks: keep that pool open and get every second of enjoyment out of it.
For my fellow fall lovers: maybe get that pumpkin spice latte iced, for now. And hold off on the pumpkin patch trip a little longer.