The hot temperatures will continue today with highs in the mid to upper 90s along with gusty south winds at 20 to 40 mph. Some temporary relief is on the way but it may come with a threat of severe storms tonight.
A major upper level system is currently to our northwest and our pressure gradient is strong today allowing for gusty south winds. Low level moisture is abundant and the warm air aloft will probably cap the atmosphere for most of the day. A few elevated showers and storms will be possible for the next few hours across the eastern OK area, but this probability is very low.
As the upper level system moves into the central plains a dry line will take shape across western OK. The surface cold front will catch up with the dry line and begin to crank out storms later tonight through pre-dawn Tuesday. The timing is still somewhat uncertain, but my best shot at this point would be from 8pm to midnight for the Tulsa metro and from midnight to 4am for eastern and southeastern OK. The atmosphere will be conducive for very strong and severe winds with storms during the first 2 to 3 hours of the event. Severe winds may be from 50 to near 70 mph in some locations. Large hail may be a possibility early in the event with a few of the discrete storms, and a tornado or two will also be possible during the very early formation of the system. The air profile aloft will support a line segment or a few line segments of storms which typically results in straight-line wind potential.
The actual cold front will stall to our northwest and will not move over the area until Tuesday afternoon. There will remain a slight chance of a few more strong to severe storms Tuesday evening as the boundary finally moves southeast of our area, but it will not move too far away. The boundary is expected to stall across north Texas Wednesday and will lift northward as a warm front Thursday morning bringing the humid and warm conditions back to the region. As the boundary is retreating northward, a few showers and storms will be possible Thursday morning across northern OK with temperatures moving back into the 90s Thursday afternoon.
The upper level pattern will finally transition into the expected northwest or west –northwest flow aloft which is a June staple in the weather department. This will create a very active weather pattern producing late night and morning storm complexes that will roll near northeastern OK and southeastern Kansas almost every night and morning beginning this weekend lasting into the early or middle part of next week. These storm complexes can produce severe weather with straight-line wind damage a main threat. And they almost always result in very little sleep for late night and early morning forecasters! I'm not a big fan of the NW flow, but the alternative is hot and dry conditions. I think most folks will take the rain but we may have to deal with several episodes of severe storms during the northwest flow period. At this point, the actual storm chances for the extended periods will remain near 30% for the late night and early morning periods.