Last week, we tossed out an idea from one particular long-range model. It showed a major cool down around September First. We are seeing other guidance move that direction now, but it does not look like the kind of ‘cool’ you might be hoping for!
That blue/green blob is good news – if it makes it this far south. That would be unusually cool weather between Aug. 30th and Sept. 4th. Don’t hold your breath, but this is showing up more and more since we first tossed out the possibility last week. pic.twitter.com/Y3PfMsP1Sy
— Jason Simpson (@simpsonwhnt) August 20, 2019
Longer-range ensembles like the EPS (European) suggest cooler air inching southward into Alabama between August 30th and September 4th. ‘Cooler’ here is relative! It doesn’t mean 60s by day and 40s by night; it most likely means 80s by day and 60s by night. At any rate, at least it’s not 100ºF with a heat index of 108ºF!
So what does the modeling show us now? These are ensembles; ensembles typically take out the extremes of individual model runs and give us a better picture of what the future could be like. It’s more about watching trends than ‘nailing’ a specific number
Both the GFS and ECWMF ensemble show a trend toward cooler but not ‘cool’ weather through early September:
By the way, the first day of Fall is just over one month away: September 23rd. Our ‘average’ final 90-degree day of the year is also around September 26th. Beyond that, the long-range guidance gives us a 25% chance (or less) of another day at or above 90ºF through October 3rd.