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Warm to Hot, But Changes Lurk

The seemingly endless warm to hot conditions with minimal rain chances continue. Low to mid-80s, nosing up to another run around 90 by week’s end will be the rule. Summer still holds on, for now. The change, though, starts next week.

The jet stream is changing and the active tropics will start to beat down the bully ridge we have seen for several weeks. It will not happen overnight, but piece by piece, it will gradually relocate and change the pattern.

The first phase, more precipitation, will begin the evolution. Still warm, but wet conditions. In Summer or Fall, rain often signals that the atmosphere is trying to cool. So the rainier we become, the cooler we will get. No, we will not be 40s and cold, but 60s and 70s, instead of 80s and 90s. The key that unlocks true fall will be the tropics.

The tropics are active. Humberto is moving away. The disturbance off the Texas coast is spinning. Newly formed TD 10 is churning in the Atlantic, and a few more waves are sliding across Africa that will play a role. All factors to end summer across the Ohio Valley.

TD Ten, soon to be Imelda, gets the ball rolling. It is forecast to curve out to sea, but I have my reservations. It could do that, but I think it runs south and starts to beat down our Great Smokies Ridge. It will not displace it but weaken it. It subsequently moves south and east to refire, then by that time “Jerry” makes a run and knocks it down some more. We are now in the latter stages of September. Up in our area, we should be wetter and cooler.

As we approach the opening of October, “Karen” and “Lorenzo” should be around. I am sure one will be homebrew development and one will be out to sea, but by this time, the ridge is on its last gasp and that is when “Melissa” or “Nestor” delivers the knockout blow to this ridge. The affectionate term “Sweeper” is given because it literally sweeps the entire Eastern Coast, delivers a big trough to the central US and Great Lakes, and welcome to Autumn. Dorian was a hint. Notice Dorian swept up the coast and delivered some great weather for a few days? Well, still being late August, the highs split and came back and we still sit in warm and dry weather.
4 to 5 weeks later it is a different story.


Current Atlantic Disturbances

Current Atlantic Disturbances

Josh & John