ST. LOUIS – A lot of research goes into making the fall weather outlook, like analyzing months of forecast trends. This year offers something quite different from past fall seasons.
It’s the tropics! This was supposed to be a big year for tropical weather. But thus far, the forecast has been anything but big to this point. There are not many complaints about that, mind you. But the causes are very real: underwater volcanic activity warms ocean waters, which then affect the air above them. Added water vapor keeps the atmosphere warmer than normal. So, all of that must go into our fall forecast.
September
We started the month on the dry side, much like we left August. Hurricane Francine brought some much-needed rain to the region, but I think that dry trend is going to continue through the end of the month. Temperatures so far have been pretty nice, with a touch of fall. Of course, we make it officially fall on September 22, but I think that summer feel is going to stick with us right through the end of the month
Last year, September was pretty warm, with some heat at the end of the month. This year, we will also end up with above normal temps. The tropics will have a chance to change that.
Rainfall last year came mainly during two bigger events at the end of the month. This year, Francine had a lot to say, but we should end up with below normal rain for the month.
October
October is the heart of fall, with sports, pumpkin spice, cool nights, and comfortable days. It’s always nice to have dry time on the weekends to take advantage of this great time of year. I think this October has the potential to align that dry time with some great weekend days.
We are generally going to stay dry this year. If the tropics decide to crank up, we may have a different story. But the widespread trends point to lots of dry time.
Temperatures may be a different story. The warmer-than-normal trend will continue this October, so maybe not the coolest of fall months on the way. It’s possible to hit 90 degrees during this stretch. Some benchmark dates to watch for: October 31 is the average first freeze, but we may be waiting until November for that kind of chill.
October 20 is the earliest first snowfall in St. Louis. While I think that potential is very low, we have to remember that October is a transition month, and severe weather is going to be a possibility.
Last October was pretty warm, with several days 10 to15 degrees above normal, including 90 degrees on October 3. This October will be warmer than normal again; probably warmer than you want it to be.
Rain last year was at a deficit, with the biggest rain event followed by a cool down at the end of the month. This year will be drier than normal too, but one or two chances could also include severe weather.
November
I’m going to just say it out loud: November is a tough month to forecast. Snow is a potential some years; see the recent examples of 2018 and 2019. November can also be mild and dry. Last year is a good example of that.
But this year, I’m leaning toward the mild side of things. The general trend looks warmer than normal all month, and I will stick with that.
Again, if the tropics come alive, that could be different. And we are still learning how solar cycles affect weather trends. We are in an upswing in solar activity, so that may play a role, too. I think precipitation trends will continue to be on the dry side for much of November. Snow should stay away this November then return for the winter, which is a whole other forecast for the future.
Last November started chilly but was mostly mild for the rest of the month, with an average of three degrees above normal. This November is another mild one, with a couple of chilly days to get you thinking winter.
Speaking of winter, last November was really dry and there was no snow in site with the mainly mild air. I think that trend will continue with a mainly dry month.
