More Heat, Chances of Rain Back in Forecast

Despite the warmer start to our day, temperatures this afternoon did not reach their full potential as happened yesterday and we wound up with a 92/72 for the max/min here in Tulsa.  Perhaps more surprising was how the dew point temperature dropped during the day as southerly winds increased to 10-20 mph with some higher gusts.  Those winds together with the full sunshine mixed out the low level moisture with somewhat drier air aloft.  That is a common occurrence but the amount of mixing was a surprise as our dew point was at 69 for awhile this morning and dropped all the way to 60 this afternoon.  Notice the dew point temperature map as of late this afternoon, courtesy of the OK Mesonet.

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Notice also the max/min temperature map, also courtesy of the OK Mesonet, and the 90s are not nearly as widespread as was the case yesterday.  Notice also how much warmer we were to start the day with most locations in the mid-upper 60s to near 70.

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We also had some fair weather cumulus clouds this afternoon which will dissipate overnight leaving us with fair overnight skies.  That brisk S to SE wind during the day today will subside tonight so look for fair skies, light winds, and temperatures again in the upper 60s to low 70s to start the day Friday.  S to SE winds of 10-20mph by afternoon will once again mix out the higher morning dew points allowing the relative humidity to drop into the low 40% range during the heat of the day.  At the same time, daytime temperatures will top out in the upper 80s to low 90s once again.  Look for some fair weather cumulus clouds to also form Friday afternoon and there may even be one or two isolated showers over the more favored terrain locations in SE OK.

Heading into the weekend, we will keep southerly winds but they should be lighter and the moisture somewhat deeper so the humidity levels are expected to be higher for the weekend going into next week.  As you can see on our forecast page, that also means our nights will be very summer-like with morning lows generally in the low-mid 70s each morning.  Daytime highs will be around 90, but with dew point temperatures generally holding around 70, even during the heat of the day, that will make the heat index more of a factor as it may reach the upper 90s.

With deeper moisture at the surface and with a ridge aloft being replaced with a more SW flow pattern by early next week; that combination will be more favorable for a chance of showers and storms to develop, particularly during the afternoon into the evening hours.  There is also the potential for a pattern change later next week with a stronger surface front moving across the state during the day Thursday.  The northerly winds behind that boundary are expected to knock temperatures back at least somewhat going into that following weekend. 

The longer range guidance is remarkably consistent in showing a rather anomalous pattern for this time of year developing late next week which I will try to illustrate with the upper level flow at 500 mb or 18,000’.  The first map shows those conditions as projected this coming Saturday at mid-day.  The ridge aloft over the state that is alluded to earlier is very evident. 

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But notice how that pattern changes by mid-day the following Saturday.  That upper level storm center will be moving at us from the NE, in other words instead of the more common W-E movement of weather systems at our latitude, this one will be coming from a general easterly direction. 

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The third map shows its position at mid-day that following Monday and has it down along the lower TX coast.  Unusual indeed; and if that does come to pass it will likely bring some locally very heavy rains our way late next weekend into early that following week.

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Again, a very unusual solution and one that will be watched closely with subsequent data runs to see if there are run to run and model to model consistencies or if this is an outlier solution. 

At any rate, stay tuned and check back for updates.

Dick Faurot