The latest complete HRRR model projections show that much of the rain will be located along and north of I-20/59 and I-20 through much of the day until a southern shift begins to happen around 4:00 pm-5:00 pm. While rain will continue over the northern half of the area, much of the heavier rain and thunderstorms will be over the southern half of the area until a movement back to the north begins around midnight-1:00 am.
This is the reason why NWS Birmingham has the Flash Flood Watch for locations mainly over the northern half of the area. Training of these heavier cells could possibly bring flash flooding to low-lying and poor drainage locations throughout the afternoon and evening hours, and even into the morning hours on Tuesday.
We’ll also have to watch for the potential of a few stronger to severe storms mainly over the western half of the area through the afternoon hours. The Storm Prediction Center has much of the western half of Central Alabama and the southwestern parts of North Alabama in a Marginal Risk for severe storms for today.
At this point, there is not enough instability for any stronger storms to form. With the heating of the day and the dynamics getting a little closer to the area, there will be the potential for isolated damaging wind gusts up to 60 MPH and a brief tornado can’t be ruled out. The main window for stronger to severe storms looks to be from 10:00 am through 3:00 pm, but I have a feeling that potential could last a little longer into the evening rush hour.
We’ll get a small break in the action late on Tuesday through the morning hours on Wednesday as most of us will actually be dry. Once we get to Wednesday afternoon, we’ll have to be on our toes. The western parts of Central Alabama have been placed in an Enhanced Risk for severe storms for Wednesday and into Thursday morning. Nearly all of the rest of Central Alabama has been placed in a Slight Risk.
The main window at this point looks to be from 6:00 pm Wednesday evening through 6:00 am Thursday morning across Central Alabama from west to east. Tornadoes and damaging winds up to and exceeding 60 MPH will be possible. Hail should not be a threat with this system.
While the setup doesn’t look too impressive at this point, the last couple of systems have overperformed from what the models projected. I’m actually worried about possible breaks in the clouds heating up the atmosphere even more than what is being projected. Highs are forecast to be in the 70s across the area. If there is more warmth across the area, that will only make the instability higher, which will lead to a higher severe weather threat. Most of the action looks to be associated with a squall line, but I have a feeling we could see a supercell or two forms out ahead of the line that could bring some trouble. The details will become even clearer within the next 24 hours.
I’ll keep you posted throughout the day today and through the overnight hours tonight with any updates to the potential for flooding and the marginal potential for severe storms. I hope you have a great day and stay dry.