After a refreshingly cool weekend, summer-like weather has taken hold again. From the crisp, coolness of Sunday morning to the sweltering heat this Tuesday afternoon, we are clearly in a transition period from the doldrums of summer to the incremental cool-downs of autumn. With that said, we are no longer dealing with triple-digit temperatures and the downward turn towards cooler weather has begun. Our temperatures will in fact be going down starting Wednesday, but it’ll be awhile before we feel those 40s and 50s again.
The cooling trend in the days ahead are directly due to the active storm pattern evolving for the second half of our week. Multiple pieces of upper-level energy will eject from a deep trough to our west and interact with the now-abundant moisture in the atmosphere. Starting this evening, a few thundershowers are possible as a weak cold front settles southward through the state. Much of this will initially stay to our west, but as the front becomes diffuse over Green Country tomorrow, spotty showers and isolated storms are possible, especially during afternoon heating.
While many places may avoid this first round of rain, most of us will see the soggy weather on Thursday as a more substantial wave rolls over. This will keep us clouded over with periods of rain and occasional thunder. Friday appears to be the wettest day as another cold front drops south into the area. It may not actually push through the region until the weekend, but its proximity with more upper-level energy overhead will spread heavier rainfall over the region. Instability will be lacking with this system, but any breaks in the clouds Friday afternoon could actual fuel late-day storms that could pack a punch. Therefore, we can’t rule out severe weather. At the very least, however, heavy rainfall will occur in some areas with a localized flooding threat.
Unfortunately, those with outdoor plans this weekend may have to have the rain gear handy. Unlike last weekend, this front may stall out somewhere nearby and keep the clouds overhead with spotty showers into at least Saturday. It doesn’t look like a wash-out at this point, but I’d count on some dreary weather to begin the weekend. By Sunday, we may clear out enough for a little sunshine. Temperatures will be held into the 80s for highs, but only drop into the 60s for lows as we don’t dry out nearly as much as behind last weekend’s cold front. Below, you'll see the jet stream pattern described earlier with the late-week system followed by the low pressure in the Southwest U.S., waiting in the wings for more unsettled weather potential next week.
The rain, despite its timing, is great news for us. We haven’t been able to shake patches of drought in eastern Oklahoma. Tulsa remains more than 7” behind our average year-to-date rainfall. Totals in the next few days like you see below will hopefully put a dent in our dryness. Many of us can count on at least an inch of water by Friday evening with more possible rain to follow.
In the longer range, a wetter-than-normal pattern may stick around. That cut-off low behind our late-week storm system (shown above) may kick out into our area next week and be another focus for showers and a few storms. This makes our Outlook, out to September 23rd, a wet one. This will keep our temperatures near their normal levels. However, no signs of cool, Canadian air are showing up around here… at least until possibly the end of next week. Therefore, we’ll have to be patient as we await another taste of fall.