It appears the mid-level ridge of high pressure will be the dominate weather feature for the next few days. A ridge is an area of sinking and compressing air with increasing pressures and temperatures. A strong ridge will keep precip and clouds away from the center while a weak ridge (dirty ridge) will still allow a few showers and storms under and nearby. Our ridge is not exceptionally strong but it’s more robust than a dirty ridge. Around late July the ridge typically becomes much stronger and can center up over the state keeping us hot and dry with no clouds in sight. We’re still in June. This is not the big typical summer ridge. At least not yet. This means our heat and humidity will get the headlines with daytime highs around 93 to 97 and THI values from 99 to 107 through the weekend with some showers and storms on the periphery of this feature. We’ll be close to some advisory level criteria in a few spots over the next few days. One or two isolated “pop up” storms can’t be ruled out, mainly across extreme eastern OK or western Arkansas during the period, but the odds will remain around 5% or so for a rogue storm at any given location.
The ridge will move eastward Sunday into Monday and this will allow a slug of tropical moisture to work its way from Texas into part of the southern plains early next week with increasing rain and thunderstorm chances Tuesday and Wednesday for some locations. This moisture will be deep in the atmosphere and will allow any storms to be highly efficient rainfall makers. The additional cloud cover will act to keep the daytime highs in the 80s once the moisture arrives, but very muggy weather will remain. Of course, things are always changing in the model data and that’s the case late last night. The position of the ridge is different in the GFS vs the EURO for early next week. I’ll stay out of the weeds for now, but the EURO is keeping most of the moisture slightly south and then west of the area early next week while the GFS has it riding up into most of the state. This EURO run is actually a big difference in the model data that would be a forecast changer regarding the rain chances next week. Precipitable water values are also lower in the EURO and higher in the GFS. We haven’t mentioned the pacific storm Bud but some moisture could work its way around the desert southwest into the central plains along a slowly advancing cold front that may enter northwestern Oklahoma to central Kansas early next week also. This boundary is also modeled differently in the GFS vs the EURO.
We’re a few days out but for now will stick with our persistent forecast of increasing rain chances for Tuesday and Wednesday with some lower temps for this period.
Before this happens, we’re back to the heat and humidity today. Highs will move back into the lower to mid-90s with south winds and mostly sunny conditions. Start pre-hydrating early with water if you’re planning to spend time outside today into this weekend.
Thanks for reading the abbreviated Thursday morning weather discussion and blog.