The rain continues to be light-to-moderate-to-heavy at times this morning. Rain like this will likely continue through midday. We might see a break from shortly after lunch through a little after dinner. But if so, it may not be much of a break. It will still be humid, breezy, and drizzly.
From the SPC
A strong upper trough is tracking across TX and northern Mexico this morning, with 75-100 knot southwesterly midlevel winds extending from the western Gulf of Mexico into parts of LA/MS/AL. At the surface, a frontal boundary extends from southwest LA into central MS. South of the boundary, dewpoints in the mid-upper 60s are streaming northward and resulting a marginally unstable air mass (MLCAPE around 500 J/kg). All 12z model guidance agrees that scattered thunderstorms will form along the front this afternoon over LA/MS and track eastward as the air mass destabilizes northward across AL. The best environment for surface-based storms, including possible supercells and bowing structures, will be in the SLGT risk area of central LA into central MS and west-central AL.
Forecast soundings in this area show substantial low-level shear conducive to a few tornadoes, but convection will likely be linear in nature, suggesting QLCS wind damage and tornadoes are the main threats. The storms should generally weaken as they track across central/northern AL, but may remain occasionally strong/severe through much of the evening.
What does this mean for South Mississippi
The front rolls through later this evening. Likely between 8p and 11p. But there isn’t much ‘umph’ back there to move it through. So it may take its sweet time.
As it passes, there will be a chance for heavier rain along it, but the threat for severe weather in our area as the front passes looks pretty slim right now. It looks like the worst of the weather should be to our north. Barely.
The “best bet” for severe weather is going to be between 3p and 7p tonight. You may be asking, “wait a second, Nick. I thought you said that was when the break was going to be?!”
You’re right! This is why weather forecast communication in South Mississippi can be really head-scratching at times. And why when I’m on TV, I understand why when I get to the end of a forecast and everyone is looking around that Minion GIF saying “WHAT?!”
So… here we go!
During our “break” from the on-and-off rain, if – again, if! – a storm can develop, it will be in the most ripe conditions for producing severe weather. The chance we get a storm to develop in that window, in our area, is around 20-percent. Not great. But not zero.
There will be another chance for a severe storm as the front passes, but I think the chance for that to happen is down below 10-percent, given the available data.
Could this change?
It would. But it isn’t likely to change. The problem with marginally unstable environments like today, there may be places where that instability is increased for a a few different reasons that are unforeseen and unforecastable.
That is why we keep such close tabs on the data.
