A mid-level ridge of high pressure will once again be the dominate feature of interest for the short term period as triple digit weather returns to the state. We look for these excessively hot readings to continue through Wednesday, but a few isolated showers or storms will be possible Tuesday through Thursday as a weak boundary slides across northern OK. A stronger front will arrive late Friday evening bringing a round of storms to the area along with below average temperatures for the weekend.
As we slide into the unofficial end to summer, it's definitely not the unofficial start to fall, as very hot readings will be likely across the entire state and much of the southern plains. Excessive heat warnings are underway for the Tulsa Metro with heat advisories issued for most of NE OK.
Temps yesterday moved to near 104 for many spots, and we anticipate readings this afternoon from 103 to 107 across the state and also in northeastern OK. South to southwest winds will provide little relief in the 5 to 15 mph range, and the fire danger will continue to be elevated despite the higher humidity. State wind burn bans remain in place for the near term future.
The mid-level ridge is expected to flatten slightly by the middle of the week allowing a weak boundary currently located to our north to slide southward. NAM data indicates a few storms will be possible tomorrow, but we think the better shot may be arriving Wednesday and Thursday as the actual boundary slides into northern OK. This boundary will either retreat northward Thursday or become diffuse.
Friday a strong upper trough will move across the northern third of the nation allowing the tail end to brush the central plains. This will drag a surface boundary into the state Friday evening with rain and storm chances Friday evening into pre-dawn Saturday. The EURO and GFS are in excellent agreement (at least at this point) regarding a Friday evening frontal passage. I have increased the pop to 50% for this period. The actual model output points toward mainly post frontal precipitation. We'll take a pass on this for now and see how the data shakes out in the next few runs.
Temperatures behind the boundary are expected to be cool compared to our current mini-heat wave with daytime highs Saturday and Sunday in the upper 70s and lower 80s. Morning lows will be in the lower 60s with mostly clear sky for the weekend.