Heavy Rain, Severe Storms Possible
Another warm and breezy day today, but the persistent clouds did keep temperatures a bit milder on the E side of the state as compared to the more western counties. Notice some of our western neighbors made it into the 90s today while Green Country was generally in the upper 70s to near 80. So far, the max;min for Tulsa has been 79/64 and you can go here to see how those numbers compare to the normal and extreme values for this time of year.
Tonight will also be very mild but big changes are on the horizon as you can see on our forecast page due to a cool front that will be pushing across the state during the day Thursday. The front together with a storm system aloft will bring much cooler conditions and also widespread showers and storms, some of which will be locally quite heavy and possibly severe. The front itself should be arriving in the northern counties first thing in the morning, reaching the I-44 corridor around the noon hour, and the more southern counties later in the day. Southerly winds and mostly cloudy skies tonight should hold us in the 60s for the overnight hours and holding generally in the 60s to near 70 before the front arrives. The boundary looks to stall out near the I-40 corridor by evening so locations south of that should make it into the 70s for a daytime high while locations behind the boundary remain in the 60s.
There will also be a good chance of showers and storms associated with the frontal boundary and although conditions are rather marginal for severe weather, cannot rule out a few storms that may contain a wind/hail threat during the course of the day Thursday.
Friday still looks to be the more interesting set up as a rather strong disturbance aloft will be moving our way bringing the potential for flood producing rainfall and another possibility for severe storms. A complicating factor is the position of the surface boundary which may try to move back north during the day. Warmer and therefore more unstable air south of the boundary would provide a more favorable environment for severe storms but so far, the consensus of the data runs keeps the boundary along the I-40 corridor. Even so, locations north of the boundary will still have a wind/hail threat due to the strength of the storm system aloft. The ultimate position of the surface boundary and its interaction with the upper level feature will be closely monitored and subtle changes of only a county or two in the location of the surface features could make a huge difference in the severe threat. However, locally heavy rainfall looks to be a good bet just about anywhere. Notice that a Flood Watch has been issued for the Thursday night through the Friday night time frame by the good folks at our local NWS office.
The data runs of the last several days have been suggesting the potential for locally heavy rainfall and the data set for today continues that trend. Notice the 3 day QPF certainly paints a significant bulls eye here in NE OK and therefore the justification for the flood watch. Keep in mind, this is an areal average which means some locations could receive much more while others receive much less, but no matter how you look at the data the flood potential is certainly a concern.
The widespread showers and storms for Friday will be moving on eastward by Saturday morning with some lingering light showers possible for the morning hours but the rest of the day is expected to be dry. The rest of the weekend going into next week will also be dry as we will be between systems for several days.
Temperatures will be going through some significant changes in the coming days as the front stalls out and with the widespread cloud cover and rain cooled air. As mentioned, locations north of the boundary will stay in the 60s Thursday due to the clouds, northerly winds, and showers while the more southern counties will be well into the 70s.
Friday will see quite a spread here in Green country with the more northern counties quite likely staying the 50s to near 60 all day while the more southern counties warm well into the 70s. Obviously, the position of that surface boundary will have a huge impact on temperatures for a given location.
Brisk northerly winds and lingering cloud cover should make for a very cool day on Saturday with morning lows in the 40s and afternoon temperatures only in the 50s. Sunday morning will start off in the low 40s but lots of sunshine will try to offset a light northerly breeze so we should make it into the upper 60s to near 70 that afternoon. After that, southerly winds along with mostly sunny skies will really warm things up early next week.
However, the trend as indicated in the 8-14 day outlook suggests the potential for some cooler air to be headed back this way and also keeps us with a unsettled weather pattern.