A complex forecast is shaping up for Monday. Some of the ingredients for strong to severe storms look to come together across the Tennessee Valley, but some ingredients will be limited, meaning there’s still a bit of uncertainty in exactly how strong storms will be.
The Storm Prediction Center has outlined a large part of the southern U.S. for the potential for severe weather on Monday.
Note that the highest risk for severe weather is southwest of us. While we do have a threat for severe storms today, our threat is more limited than for those in parts of Mississippi, Louisiana, and west central Alabama.
Despite our lower threat, the environment here could still support storms capable of strong straight line winds, heavy rain, and perhaps a couple of spin up tornadoes.
Storms will begin in the mid afternoon and continue off and on through the late evening.
So, lets talk about why our risk here is a little more limited than it is further southwest. We will have plenty of wind shear for thunderstorms to tap in to on Monday.
That’s why we can’t rule out a couple of spin up tornadoes. There’s enough wind shear to support them on Monday. Despite the wind shear, as is often the case in winter, our limiting factor will likely be a lack of unstable air.
That’s CAPE (Convective Available Potential Energy). It’s essentially a measure of the amount of energy in the atmosphere a thunderstorm can use to make stronger updrafts. CAPE in north Alabama will be more limited, with higher values to our south and west, particularly in Mississippi and Louisiana. This time of year, a lot of our potential severe weather setups are high shear/low CAPE. The lack of more unstable air Monday looks to be our limiting factor. Despite this limiting factor, there may be enough CAPE to support strong winds and a few rotating updrafts that could produce brief tornadoes.
While this doesn’t look like a high end event, you still need to have a way to receive weather information like Live Alert 19 or a battery powered weather radio. If you get an alert a dangerous storm is headed your way, you can tune in to WHNT for more information. Know what to do if a tornado warning is issued for you, but for most of us, it will probably just be a stormy and windy Monday.
Meteorologist Alex Puckett