Change isn't always easy, and that is true for seasonal change in Oklahoma. Both in the spring and fall, we enter this period of time where just the right ingredients come together for explosive storms (not to mention a roller coaster ride with our temperatures). While springtime in Oklahoma is notorious for severe weather, October into November can bring some wild weather to the state. From now through the weekend, we will see some of that play out.
The polar jet stream, which retreated to the north all summer, is plunging south now as cold air begins to pool in the higher latitudes. That jet stream brings stronger storm systems to our part of the country while we still have enough heat and moisture available to produce storms of consequence. The jet stream will be oriented in such a way that brings wind shear as well. Those ingredients will come together over the next couple days to bring us the risk of several rounds of strong to severe thunderstorms.
It may catch some of us off-guard. We essentially jumped from summertime heat to literally freezing cold temperatures in the matter of a few weeks. Despite having our earliest freeze on record in Tulsa, heat and moisture are returning to fuel storms as early as Friday morning. This initial round of storms won't be as organized, but may produce very heavy rain and large hail at times. Flash flooding may even be a concern. The best chances of rain will lie across the northern half of the state near a stalled frontal boundary.
As we head into the weekend, a stronger, upper-level low will bring much more energy to an already warm and moist air mass. The result: a round of severe weather Saturday afternoon and evening that may remind us of April or May. This low has been waiting in the wings, cut off from the main flow of the jet stream for weeks near California. As it finally surges by to our north, we could end up with an intense line or broken line of storms with high winds, hail, and a tornado or two. Needless to say, we will have the WARN team geared up for the event to help keep you informed and safe. The map above shows the outlined risk area for Saturday. The higher percentages correspond to the highest risk of seeing severe weather, which will be just north of us in the direct path of that upper-level low.
With a very active jet stream and the occasional pull of warmth and moisture from the south over the area, the weeks ahead may feature more severe weather chances. Be sure you are aware of your severe weather plan and have an emergency kit ready to go. As we know in Oklahoma, dangerous weather can happen at almost any point in the year. It's just that autumn, aside from nice, crisp days, can also bring wild temperature fluctuations and intense storms. I'll keep you up-to-date on Twitter: @GroganontheGO and on Facebook. Be sure to "like" my page!