Congratulations! You have made it through Tulsa’s hottest day of 2019. With a low of just 78° and a high back above the century mark, our average temperature was about 8° above normal. It was a long wait to *officially* hit 100° this summer at Tulsa International Airport (our first day was Monday) despite numerous days with a heat index well above that mark. Without even looking at the rain gauge, that is a strong marker of a wet year. We pay for the lower number of triple-digit days with high humidity resulting in an oppressive heat index. Tuesday’s maximum heat index values are shown below. We could have a third day around 100° Wednesday before welcome relief arrives. And given how late it is in the summer, we may be done with that level of heat for the season – more on that below.
An offshoot of the jet stream well to our north is sending a disturbance southward that will cool us off and raise our rain chances in the coming days. The first wave may impact areas from Tulsa northward on Wednesday night. The weather pattern is shown in our map above. A frontal boundary brought southward will then stall out near or just north of the area through late in the week. A nightly strengthening of the low-level jet stream (winds just above the surface) will trigger widespread showers and thunderstorms through Friday night in our area with the highest rain chances remaining over northeast Oklahoma. Lingering showers and a few storms may linger or bubble up in the daytime hours as well. Below is our rain timeline. A few thunderstorms starting as early as Wednesday evening could be severe with high winds posing the great threat. However, severe weather will only happen in localized spots if at all.
More clouds and occasional rain will drop our highs by about 10° from current levels. Unfortunately, the moisture will quite literally stick around. That means the late week timeframe will still be quite muggy. The projected heat index each day is shown below.
The slow-moving disturbance will gradually slide out of the area over the weekend. By then, a couple inches of rain will be in our buckets across portions of northeast Oklahoma. Parts of southeast Oklahoma may have a nice soaking as well, but the higher amounts will not likely be widespread. Recent heavy rain events have occurred near the Oklahoma-Kansas border so additional thunderstorms could cause flash flooding. South of Tulsa, people will take every raindrop they can get as we are rapidly approaching a drought otherwise. Below is a generalized rain forecast for Green Country, likely ensuring we will stay green into the fall.
As the clouds break up this weekend, the heat will build back into the area. It will be another good window of time for the pool! You can count on high humidity once again, but the temperatures are not expected to soar as high as now. The heat ridge will be centered a little further west.
The jet stream to our north becomes more energized next week, sending a stronger storm system to Oklahoma next Wednesday. This could bring about more thunderstorms, and more importantly, give us a significant cool-down along with lower moisture levels. The final few days of August into Labor Day weekend could be a nice fall preview. Our outlook through the holiday weekend shows much below average temperatures projected for our area. There is serious heat relief in sight!