Heat warnings will continue to be the major headline today but a few scattered thunderstorms may also occur as a boundary approaches the area this afternoon and tonight. The warm air aloft ( the cap) will more than likely suppress most of the activity but even a small weakness on the eastern periphery of the ridge would allow a storm or two to develop. Additionally, the ridge is already moving westward and will eventually be centered well west of the state during the next 36 to 48 hours. This will occur as another pattern change develops across the nation with a trough across the eastern third of the nation and the ridge expands across the west and southwestern U.S. This pattern will support below normal temps from the Great Lakes to the east and very hot weather across the western and southwestern part of the country. Eastern Oklahoma will be in-between these two features but will be influenced more from the eastern trough by the middle of next week. This will bring some welcomed relief after this weekend with near or even below normal temperatures for a few days before they crank back up.
The local dew points didn’t budge yesterday for most locations and heat index values shot up to 110 to 120 in some locations. Today local dews should be varied due to the trough approaching the area. Drier air will sneak into the I-44 region along and ahead of the boundary. Locations to the southeast of the front and on the far northern side of the boundary may see moisture pooling through midday to afternoon. This will create a broad range of THI values and temps, but both areas would fall into the heat warning criteria. Some locations will have highs nearing 105 to 113 while other spots will have THI numbers from 105 to 118. The metro highs are fairly tricky today with 50-degree dew points already positioned across west central Oklahoma this morning. If we get a decent southwest flow by midday to afternoon with a taste of these 50 dews, the Tulsa temps could soar into the 110 to 112 range. I’ll more than likely stick with a high around 107 to 109. A last second game time decision.
We would typically not include a storm chance with a 594DAM ridge influencing our area, but the positioning of the ridge and the westward movement continues to support a narrow northwest flow that will brush our area. A few showers and storms survived the trip from Kansas into northern Oklahoma overnight and we’ll keep another slight mentioning in the forecast as the front approaches the area later today and this evening. If they do develop, they could deposit damaging down bursts of winds in a few spots.
Highs this weekend continue to look lower in the operational data versus the ensembles. We’re sticking with some of the warmer ensemble data with readings in the upper 90 Saturday and mid-90s Sunday for the northern sections with southeastern Oklahoma remaining in the 100 range Saturday afternoon. There should be some dry air for part of northeastern Oklahoma Saturday afternoon or even Sunday while the southern sections may continue to be in a higher moisture rich area.
Thanks for reading the Friday morning weather discussion and blog.