Hot & Humid, Chance Of Showers/Storms

Thought the map showing the percentage of normal rainfall over the last 30 days would show more clearly how dry many locations have been since the latter part of May.  As you can see, some of us have only received 20-40% of our normal rainfall and given the warmer temperatures at this time of year which in turn leads to evaporation rates in excess of 0.25” per day, it is no wonder it is rapidly becoming very dry.

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Our next chance for any relief in the form of a more widespread shower/storm event still looks to start on Friday and continue into the coming weekend.  Some changes in the wind flow aloft will allow a weak surface front to move into the state on Friday, stall out, and eventually become diffuse over the course of the weekend.  However, the presence of the boundary together with more moisture availability and a weakness aloft should produce several rounds of showers/storms starting during the day Friday, through Friday night, and into the day Saturday.  Given the very weak wind flow aloft, those showers/storms may well extend into Sunday.  As you can see, the 7 day QPF is still optimistic regarding the rainfall potential with several inches possible.  Quite frankly, those numbers look to be on the high side but some locations could end up with a real soaking and we certainly do need a good rain.

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Between now and then, look for stronger southerly winds for Wednesday and Thursday and those winds will bring higher dew point air back over us resulting in higher heat index values.  Dew points should be in the low 70s for the afternoon hours and with air temperatures reaching the low 90s, that should push the heat index into the upper 90s and perhaps even near 100 for some locations.  So, be careful with the outdoor activities.

That will be quite a change from recent days in which the lower dew points have allowed our nights to drop into the low-mid 60s and the relative humidity during the heat of the day has dropped into the 30% range which is very pleasant for this time of year.  Today was a little more humid as the relative humidity stayed in the 40% range this afternoon and so far, the max/min in Tulsa has been 89/65 as compared to the normal values of 91/71.  

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Then, the rain chances start ramping up on Friday through the weekend and the extra cloud cover together with some cooling showers around will knock our daytime highs back into the 80s as you can see on our forecast page.  This event is still far enough down the road that the specifics regarding timing, location, and amounts will be fine tuned in subsequent model runs and forecast discussions.

In fact, going into next week and for the fourth of July itself, the current data runs suggest we may have a weakness aloft lingering in the vicinity so that at least a few showers/storms cannot be completely ruled out.  Even so, look for the heat and humidity to be more of an issue by then.  In fact, the 8-14 day outlook suggests above normal temperatures along with a near normal pattern of scattered showers/storms.  By then, our normal daytime highs are in the low 90s and storms are at best on a scattered basis.

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So, thanks for reading the blog and stay tuned for updates.

Dick Faurot