Another hazy, smoky appearance will be expected in the sky on Wednesday along with below normal temps but changes are expected to bring heat and humidity back to the state this weekend.
A broad trough in the upper levels positioned across the far NE U.S. and a ridge of high pressure to our west will keep northeastern OK in a favorable position for below-normal temps on Wednesday and most of Thursday before the pattern changes this weekend. While a very small chance for a couple of showers and storms will remain at times, the overall story will be the return of summerlike weather, including heat index values moving over 105 this weekend into most of next week. We still have plenty of summers left on the horizon.
Temps are currently in the 60s, even a few upper 50s in sheltered valleys this morning with afternoon highs forecast for the upper 80s with 90 near the Tulsa metro. A few small diameter showers will be possible across extreme southeastern or east-central OK, but the chance will only require a few mentions.
The mid to upper-level flow is also favorable for more haze and smoky sky across part of the area on Wednesday but should be lessening some soon. Wildfires across the Pacific Northwest and the Canadian intermountain region have been underway for weeks, if not months in some locations, with thick smoke traveling thousands of miles across the United States, including to Oklahoma. The ridge to our west will flatten and the trough to the east will move eastward allowing a quick zonal or west to east flow development across the central plains Thursday through the weekend. At least two distinct waves will enter the plains, including one Thursday evening and a stronger system this weekend to our north.
As the Thursday wave nears the state, we should see more cloud cover compared to recent days and we'll have a low-end chance for a few showers or storms as the wave nears the area. A more favorable location will be across southeastern Kansas, but I'll continue with low mentions for northeastern OK. Possibly more important is the response expected at the surface with southerly winds returning low level moisture across Eastern OK beginning Thursday and continuing through the weekend. Combined with increasing temps, heat index values are likely to approach the lower end of advisory criteria this weekend in some, but not all locations.
The 2nd disturbance is stronger and will move across the Dakotas Saturday keeping most of the storm activity to our north. But the tail end of this wave will have a chance to enter northern OK late Saturday night through Sunday morning bringing a few showers or storms nearby. This probability also remains low, but not zero.
We're moving into what is normally considered the hottest part of the year from a climate standpoint. All of this to remind us that we have plenty of summerlike weather to experience before the downhill slide to autumn occurs. GFS operational data is warmer early next week compared to the EURO, but we’ll be siding closer to the GFS for now.
The tropics have remained very quiet this past three weeks due to the presence of the Saharan dust layer and generally unfavorable conditions. The overall pattern will also change soon allowing for more development through September.
Thanks for reading the Wednesday morning weather discussion and blog.
Have a super great day!