It’s the summer that seemingly does not want to end. Every single day of September has been warmer than average for Tulsa with the entire month running 7 above normal°. When every day except for one has had a high in the 90s and the coolest reading has been 67°, this month far more closely resembles August. So far, this is the 6th warmest September on record for Tulsa. Will fall ever arrive?
While summer may not break anytime soon, we have relief coming in from the Tropics, of all places. The brief Tropical Storm that formed off the Texas coast has moved inland. The remnants are drifting north toward Oklahoma with abundant moisture and more cloud cover. This will result in rising rain chances as we approach the weekend. That will send our highs back into the 80s by Friday. However, no cold front will accompany this storm system, which means we just transition from sweaty to soggy. Below is the overall jet stream set-up showing the Tropical low being brought northward around the west side of the high pressure ridge. Colder air remains locked up north.
However, the jet stream is active and will send more upper-level energy overhead to trigger more widespread rain and t-storms over the weekend. The focus will shift from southeast Oklahoma to northeast parts of the state giving Tulsa the highest rain chance on Saturday. The severe threat will be low with limited parameters for strong storms, but flooding rainfall could be an increasing threat with the upper-level, steering winds promoting training thunderstorms. 1” to locally 4” of rain may fall by early next week. Below is the weekend rain timeline and potential rain totals into early Sunday.
By Monday, the jet stream re-loads with another trough over the west, forcing the hotter air and high pressure ridge back into the Southern Plains. So you guessed it - the temperatures will go back to 10° above normal as we move into the final days of September. Widespread showers and storms will gradually taper off early next week with the storm track shifting back to our north again. That means the Pineapple Whip and Ice Cream Cones will be the “hot” item again as we kick off the Tulsa State Fair later next week!
Even as we look into the early days of October, hotter than normal weather is likely to persist. What we need is a serious kink in the jet stream over the central U.S. The map above shows that will not be in the right place to open us up to Canadian air early next week. As we move deeper into autumn and cold air builds at the Poles, that air will much more readily expand southward. It is just taking its dear sweet time this year. Even as we switch to the fall season officially on Monday, carry on with your summer ways until further notice.