Out of the last 3 weeks, only 2 days have had a high temperature lower than 90°. That would be summer as usual in July or August, but by this point in September, we're used to seeing our first wave or two of cooler, more fall-like air. That is reflected in our rapidly-decreasing average high and low temperatures as we also quickly lose a lot of daylight. Did you know our average high for this week is in the mid-80s? You sure wouldn't know that by the mid-summer readings on our thermometer!
As I've mentioned recently, the heat's days are numbered and we know the heat will scale back further by late week as a weak cold front comes into the state. Until then, the heat will slowly subside as the high pressure/heat dome finally shifts to our east and weakens.
The streak of days without rainfall is a growing concern, especially with these hot temperatures which act to enhance evaporation and dry out the ground. The first attached map shows the consecutive number of days with less than .1" of rain on any given day. We're approaching 4 straight weeks of no significant rainfall. If it wasn't for our August wet spell, we'd be in a world of hurt already. We've all seen the signs of drying vegetation though, and official classification of a drought in our area is likely to come this week.
Thursday's cool front doesn't hold much promise of soaking rainfall. While showers and storms will occur in spots, the relief we need won't really be found here. What will be found are slightly cooler temperatures. By that point, highs in the upper 80s are still above-normal, but it's a nice change! A more significant change may be on our doorstep early next week as a stronger cold front makes an approach at Oklahoma. This time, there is a stronger signal for rain and a stronger push of cool air!
Will that cool air last? Well, the Climate Prediction Center isn't too optimistic about that. Their 8-14 day outlook pegs us and much of the central U.S. in above-normal temperatures once again. While our actual temperatures may gradually be dropping, we are well behind other years in our transition from one season to the next. More than anything, we need a return of an active weather pattern to bring us relief in the moisture department. Tulsa's growing rainfall deficit (now over 5") speaks to that clearly. We were on the right track in August, but this hot, dry spell of weather for weeks on end won't be remedied overnight.
What would be most helpful would be the remnants of a tropical system to bring us a steady, soaking rain. ‘Tis the season! There is some activity at the moment, but the only named storm is closer to the African coastline than North America and that tropical storm, Humberto, won't come close to reaching us. We're at the height of the Hurricane Season now and only a few other years can boast no hurricane by this point in the season. Now that's a positive trend, but one that won't help us get out of our growing drought.