Notice the maximum heat index for today, as measured across the state by the good folks at the OK Mesonet.
Then compare that with the max/min temperatures for today and it is apparent that the combination of heat and humidity has become more of a factor in our weather.
You may recall that the dew point mixed out with drier air aloft yesterday which kept the heat index value at bay. That did not happen so much today as the moisture has deepened just enough for the mixing to be minimal. I mention all that because it appears that the dew point will likely remain in the upper 60s if not the lower 70s through the weekend and well into next week.
That means our nights will not be cooling off much and our days will see heat index values that will at times be in the very uncomfortable range. In other words, as a general rule add another 3-6 degrees to the air temperature to arrive at the heat index during the heat of the day. Since the higher dew point temperatures are a direct measure of the amount of moisture in the air and instead of being confined to just the surface it will be through a deeper layer of the atmosphere, that also means we will see a little more cloud cover. However, despite the partly cloudy to at times mostly cloudy skies, it will still not take long to get a sunburn as you can see on the UV Index which will remain in the high to very high category.
Fair to partly cloudy overnight skies along with a light S to SE wind should result in morning lows around 70 if not the lower 70s in the days ahead. Partly cloudy to at times mostly cloudy daytime skies should limit our daytime highs to the lower 90s through the weekend and into early next week, but that is well above the normal value of 88 at this time of year. We will keep a southerly wind of 10-15 with a few higher gusts during the day but lighter winds at night. Also, the available moisture over a deeper layer together with the daytime heating should be enough to set off a scattering of showers and locally heavy storms. If you are lucky enough to be underneath one of those, they will really cool things off and will be capable of dropping torrential rainfall in a short period of time.
But, although the chances it will rain somewhere in NE OK will be near 100%, it will not rain everywhere and the chances of it raining at any one location will be on the order of 20% Saturday and somewhat higher for Sunday into early next week as you can see on our forecast page. Notice also there will be very little day to day variation in temperatures until later next week.
A weak front or at least a wind shift now looks to arrive late Thursday or early Friday shifting our winds to northerly. That should knock temperatures back at least briefly and bring somewhat drier air back over the state. That should also be the end of the scattered showers/storms that will be possible up until that boundary moves through. Any cooling behind the boundary looks to be short lived and the anomalous upper level flow pattern noted in yesterday’s discussion is now looking more and more like an outlier. The upper level storm system noted then is now expected to remain much further east which is a more reasonable solution than the retrograding system suggested with the data runs from yesterday.
Notice the long range guidance over the 8-14 day time frame continues to suggest we will be warmer than normal and also drier than normal. That will make any decent rains we may receive over the weekend into next week all the more important as things are starting to dry out.
At any rate, stay tuned and check back for updates.