While Central Alabama is experiencing a very pleasant early May evening, a large thunderstorm – or perhaps a cluster – was moving steadily across Mississippi. Some severe thunderstorm warnings had been issued, but at this writing around 7:30 pm, there were no warnings in effect with this storm complex as it was crossing Interstate 55.
One of the big questions that always arises when we see one of these big thunderstorm complexes is just how long can it go? The answer to that, of course, depends on many, many factors. In my career, I’ve seen thunderstorm complexes go from the Central Plains to the Gulf Coast in 24 hours or less.
So let’s look at this one since it has the potential for impacting Central Alabama.
One factor against it is the sun is setting. So one ingredient should be on the downturn as the setting sun takes the heat factory with it. But the storm is moving into an environment that is somewhat favorable with temperatures in the mid and upper 70s and dew points running in the mid and upper 60s.
Supporting the cluster is a moderate jet with 30 to 40 knot wind around 500 millibars. Also contributing favorably is that remnant surface boundary that plagued us last week. That old boundary is hard to find since it is not particularly strong, but seems to be detectable in the temperature and dew point fields.
There also appears to be favorable low level easterly flow feeding good moisture into the complex.
All in all, I think there is a reasonably good chance that parts of West Central and Central Alabama will experience this cluster tonight. The main areas I think will get the thunderstorm would be bounded by Russellville to Cullman to just east of Birmingham to north of Livingston including spots like Tuscaloosa, Aliceville, Carrollton, Northport, and Vernon. But I also think the storm will remain below severe limits with wind gusts potentially into the 40 to 45 mph range.
I do not think it will last much after Birmingham due to a more stable environment.
Now that I’ve stuck my neck out, I’ll just sit back and see what happens.
-Brian-
