Our secondary severe weather season has arrived. While ingredients for severe thunderstorms come together more frequently in spring, we can certainly have a few episodes of dangerous storms this time of year. The risk is with us Tuesday evening as a potent storm system develops to our west that could spread severe weather into Green Country. Here’s the breakdown of this first round.
Not everyone will see the storms tonight. It is more likely storms will fire along a boundary in western Oklahoma into southern Kansas after 4pm and travel northeastward, making a run at areas northwest of Tulsa initially. Those will pose a threat for high winds, large hail and an isolated tornado. The highest risk for any tornadic activity will be across the deeper moisture and best shear environment in north-central Oklahoma along and just west of I-35. Overnight, storms may congeal into a cluster and push eastward. If this does occur, southeast Kansas into far northeastern Oklahoma stand the best chance for this activity. Strong winds with a secondary threat for some hail are the primary issues. These storms will gradually weaken as they push eastward into a more stable environment. Below, you’ll see the latest severe weather outlook putting the highest risk for severe weather to our northwest. In any case, it’s a taste of spring in the fall.
It may feel more like the summer both Wednesday and Thursday as moisture levels continue to increase. With at least partial sunshine, temperatures may near 90° in the afternoon, shoving the heat index into mid-90s. Yuck. We won’t quite be in record territory, but considering the average temperature range for this time of year is from the mid-50s to the mid-70s each day, this is certainly unseasonable.
The next big round of storms may not arrive until Thursday night, but a few pop-up afternoon or evening storms are possible on Wednesday between systems. Any remaining boundary in the area could be a focus for scattered storm development given the hot and humid air mass in place. Once again, the northern areas would be most susceptible to this threat.
Thursday evening, a stronger wave will finally arrive in the flow of the jet stream, pushing a cold front into our region. Strong convergence along that surface front will trigger a line of storms, a few of which could be severe Thursday evening before being undercut by the advancing colder air. Whether or not severe weather comes to fruition then, heavy rains are expected that night into Friday morning with the heavier rain totals in northeast Oklahoma versus further south. That is because forcing will increase with northward extent. This front will finally clear us of this active, spring-like pattern, allowing much cooler, drier air to settle in for the weekend. Be ready for a shock to the system as temperatures near 90° Thursday afternoon give way to 60s for highs on Friday with a brisk north wind! The weekend will be fantastic as crisp cool mornings and mild afternoons are expected with mostly clear skies. This will be an ideal way to end the Tulsa State Fair!
I would be remiss if I didn’t mention the powerful Hurricane charging northward through the Caribbean. With peak winds of 145 mph, Matthew continues to be a Category 4 Hurricane (second strongest category), ravaging the western tip of Haiti and the eastern extent of Cuba. From there, the computer models steer this system further west due to a high pressure ridge to its east. This has big implications for the southeastern U.S. coastline. Just how far west Matthew goes is the big question, but it appears likely it will brush the shore of Florida and possibly make landfall in the Carolinas before ejecting northeast back out to sea thanks to our late-week storm system, giving it that eastward boot. The projected path as of Tuesday afternoon is shown below.