re: Mardi Gras Weather Thread

Looking ahead to Sunday, it's trending wet and potentially stormy. For all my talk about no thunderstorms being likely, it seems the atmosphere disagrees. Won't be the last time.

First off, the front.



There's greater agreement of our cold front coming through Sunday night. The image above shows cold air advection, the lateral movement of cold air, at about Bacchus roll time. It's the lead up to the front passage that is of concern, since it's trending toward being more supportive of thunderstorms.



GFS sounding for around New Orleans at noon Sunday. There's some instability to suggest convection (heavier rains and potential lightning). This doesn't mean a blanket of storms but I'd think scattered storms with marginal severe potential. Going to keep a close eye on this.

Another sign of the rain potential shows up looking at the lower level and upper level winds. There's some lower level convergence (air coming in toward the same point) which brings in a source of warm moist air. Then the uppers...



You'll notice how the streamlines start going off in different directions and the speed loses intensity along SELa over NE toward the MS coast. You've got divergence aloft, providing a means of pushing what lifts out and away. This can enhance rainfall in the area.

I'll note it doesn't mean it will happen, just potential to be mindful of going forward. These sorts of details are far form set in stone, so be mindful. Still room to change over the next few days.