Don't want to get your hopes up too high, but notice the QPF(Quantitative Precipitation Forecast) map on the right. This particular forecast graphic is valid from 7PM Sunday through 7PM Monday and actually shows E OK with some precipitation for the first time in what seems like forever. Now don't misunderstand, that does not mean that all of the area depicted will receive that much rainfall or that it will rain everywhere within that area. It does mean that we do have the possibility of rain and that the areal average should be on the order of ¼ inch. I may be a little conservative, but right now I am putting the actual chances of any one location receiving measurable rainfall at 20%, which of course means most of us will miss out. Also, those showers/storms that do form will be capable of dropping locally heavy rains in a short period of time; keep in mind the map on the right is an areal average.
So, if you happen to catch a good rain on Monday, count your blessings as any showers/storms are expected to be rather spotty. One benefit we will all receive though is at least a little break in the triple digit heat. The extra cloudiness during the day along with somewhat cooler temperatures aloft will combine to keep us in the low-mid 90s for most locations on Monday. In fact, we have been getting a taste of that today as surface temperatures are running a couple of degrees below the same period 24 hours ago and we expect that trend to continue again Sunday. Although Sunday is expected to be dry, we will see a few more clouds in the sky and temperatures for the most part should stay just below triple digits.
The reason for this is a weakness in the dominant upper level ridge that has been centered over the state. This weakness is associated with somewhat cooler temperatures aloft and will also allow some moisture in SE TX to work up this way. Thus, a few more clouds on Sunday and partly cloudy to even mostly cloudy skies at times on Monday. Unfortunately, this system will be weakening as it drifts over E OK Monday, but at least we have the chance of rain and the clouds will provide a bit of a break in the heat. Of course, the humidity will be a little higher but that is a small price to pay if we can at least get a few showers.
Speaking of the humidity, it has dropped to below 30% this afternoon at many locations and will likely drop to near 30% during the heat of the day Sunday. Together with a brisk southerly wind and the drying and stressed vegetation, that will also make for an enhanced fire danger situation on Sunday.
By Tuesday, the system aloft will be replaced by the strengthening ridge for the rest of the week so look for temperatures to be back around triple digits on Tuesday and at or above triple digits for the rest of the week. Also, after Monday there is little or no mention of any additional shower activity.
So, stay cool, stay tuned, and check back for updates.