It’s a steam bath out there and we’re not even officially to the start of the summer season yet according to the calendar. While the heat today (and possibly tomorrow) may contribute to a few storms, the waterworks are gradually shutting off as a summer heat wave is upon us. We had the latest 90° day in the year in 23 years, and now it seems Mother Nature is making up for lost time.
In the short-term, the severe thunderstorm threat is the main concern. A fast-moving wave of energy is passing well to our north, but might act as enough of a trigger for storms to form along and ahead of a trailing frontal boundary extending southward through Kansas into western Oklahoma. The threat is “conditional,” which means storms may or may not fire due to the CAP (or warm air suppressing rising cloud development). However, IF those storms form, they would likely be severe if they can maintain themselves. Hail and high winds are the primary threats given a weakly sheared environment. The main threat for storms will fall between 4pm and midnight for parts of Green Country, particularly north and west of Tulsa.
Any residual boundaries left from storms on Wednesday could be a trigger for isolated storms that afternoon, but the CAP will be stronger and the upper-level support will be even less. Still, a very low risk of severe storms does exist both today and tomorrow in northeastern Oklahoma.
The heat is the biggest story going forward. A classic “Heat Dome” is building as a large ridge of high pressure in the jet stream (shown below) steers all storms up and around it.
There’s nothing to really shove that humidity out of place through the end of the week. Thus, the increasing heat and sunshine combined with higher levels of moisture in the air becomes a dangerous combination. Already, a Heat Advisory is in effect for parts of the area, including Tulsa, on Wednesday. This will likely be extended later into the week and possibly the weekend as little changes over that time frame. Begrudgingly, I’ve had to keep inching those high temperatures up into the upper 90s. This will translate to heat index values between 105° and 110° each afternoon Wednesday through at least Friday.
Is there any relief in sight? The short answer is not much. The heat dome will re-orient itself a bit over the weekend and might send *slightly* cooler and drier air our way from the east, but above-normal temperatures still appear likely well into next week as no significant pattern change appears to be on offer. We may be dealing with unseasonably hot weather as we head all the way into the end of the month. This goes hand-in-hand with a drier than normal pattern as well. I think we’ll see lots of sprinklers watering yards here before too long. It’s hard to say if the newly-emerging La Niña is already having an effect, but this is certainly characteristic of a La Niña summer in Oklahoma… hot and dry.
Take it easy in the heat and don’t forget to take extra steps to protect your pets as well. We have not had much time to acclimate to these kinds of readings! Be sure to follow me on Twitter: @GroganontheGO and like my Facebook page for more weather updates!