Get ready for a big warm up today across the state along with gusty southwest winds from 15 to 25 mph. Afternoon highs in the Tulsa area may approach 90 today with some locations across far western OK nearing 100. A cold front will be entering northern OK by Thursday before stalling and retrograding into southern Kansas Friday. The front will finally get a shove southward Saturday morning bringing some cooler air this weekend with opportunities for passing showers or storms during portions of the weekend.
The upper air flow remains from the northwest through tomorrow morning yet the mid-level ridge to our west begins to expand westward. This will bring the warmer conditions to the state, but we may still experience a few early morning showers or storms Thursday pre-dawn. The favored location would be to the northeast of Tulsa and we'll keep this mention around the 10% probability.
The main upper level low of interest will brush the northwestern part of the state Friday. The dynamics with this upper level system are very strong, but the layer of warm air aloft ( the CAP) will more than likely suppress surface based thunderstorm activity across most of the state Thursday night and Friday. I must stress that severe weather would be likely if the CAP doesn't hold and thunderstorms form in the warm sector. We think most of the shower and storm activity Friday evening into Saturday would be post frontal or slightly elevated and this would limit the severe weather threat.
The big issue this morning centers on the weekend front and how far southward the front may or may not move. Model data from the past few days indicated a big push of cooler air with the front sliding well into Texas. The last run of the GFS has performed another classic flip with warmer air, while the EURO is now backing off the cooler air compared to the previous runs but is cooler compared to the GFS machine numbers. Here's what I have decided to do regarding this issue: I will make some adjustments up from our previous forecast of mid 60s for Saturday, but not nearly as high as the MOS numbers which would suggest some mid-70s Saturday and almost 80 Sunday. Obviously the confidence level is very low with the extended numbers for weekend highs, but surprisingly, we feel pretty good about a 20 to 30% chance of showers or storms Saturday and Sunday.