Hard to believe that our daytime high yesterday was 81 and today’s afternoon temperatures have struggled to get much above 50 as you can see by the 24 hour temperature change map, courtesy of the OK Mesonet. In fact, the maximum temperature for this date in Tulsa has been 61 at about 1:30 this morning and the highest so far this afternoon has been 54. Here is a link to the normal and extreme values for Tulsa.
The cloud cover, lingering showers, and brisk NW winds have certainly contributed to the big drop in temperatures for today. That will be followed by clearing skies tonight, in fact our skies are gradually clearing from W-E as I write, and much lighter winds by morning. As a result, look for a very cool start to our day with morning lows possibly in the upper 30s for some of the cooler valleys of NE OK and lower 40s elsewhere.
Thursday will start off with lots of sunshine but high level cirrus clouds will be on the increase as the day wears on in advance of a system that could set off a few showers or storms that night. Our winds will be returning to a SE direction at 10-15 mph so temperatures will still make it well into the 60s if not near 70 for a daytime high. As mentioned, a few showers or storms will be possible that night, primarily over the more northern counties and that will be followed by a much more interesting scenario for Friday night through the day Saturday.
After any Thursday night storms move on east, the balance of the day Friday should be warmer and dry until late in the day or more likely that night. Southerly winds will keep us much milder to start the day with morning lows generally in the 50s and daytime highs should make it into the 70s. But, a significant storm system is brewing to our west and by mid-day Saturday, the upper level storm center will be over NE New Mexico as you can see on the map. This is for the 500 mb level or about 18,000' above sea level and the colors depict the strongest winds at that level.
Those southerly winds aloft together with a surface frontal boundary that will stall out here in NE OK means a prolonged period of showers and storms, some of which could be severe and with a significant threat of flooding rainfall. Notice the projected QPF amounts through this weekend; this could turn out very similar to last Friday and may even drop more rain than occurred then.
This next map is the preliminary storm zone and keep in mind this is very preliminary. The position of the surface front will be critical in where the most significant severe weather occurs. Locations south of the front will be warmer and more unstable and all modes of severe weather will be possible. Locations north of the front will be much cooler which would limit the tornado potential, but damaging winds and hail would still be a threat. And, as mentioned, all locations have the potential for significant flooding. Right now, it appears the frontal boundary will stall out somewhere between I-44 and I-40 but that may change significantly over the next few days. Keep in mind, the storm system of interest is currently out in the Pacific so there remains considerable uncertainty regarding its precise track, timing, and intensity.
By Sunday, that storm system should be ejecting to the NE putting us on the backside which means another very cool day on Sunday with possibly some lingering light rain or drizzle. As you can see on our forecast page, that is expected to be followed by a return to sunny skies, southerly winds and a nice rebound in temperatures for early next week.
Not for long though, as the 8-14 day outlook continues to suggest temperatures on average will be below normal but at least it also looks like a more normal pattern for showers/storms as we head into May.
So, stay tuned and check back for updates.