re: Preliminary Ratings: Lacombe Tornado - EF1; NOLA/Arabi Tornado - EF3

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I keep going back and forth if there's enough to ENH SELA. Is slight+ a thing? HRRR doesnt quite destabilize the boundary layer for SELA, and thats really the question. Does the low level flow kill the marine layer and get us mixing at the surface?

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An increase in tornado probabilities was considered with this outlook over portions of southwest MS and southeast/east-central LA for the potential for surface-based storms near the warm front, where a conditional risk for a significant tornado will exist. However, with concerns regarding a tendency for veering 850 mb flow during the 08-12z time frame have opted to maintain current categorical/probabilistic risk levels and shift tornado probabilities north across portions of southern MS/east-central LA. Additional adjustments to the risk in this area may be needed in later outlooks.

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We all know that means it’ll be focused up there instead of down here near Baton Rouge and New Orleans. That’s how it almost always is because of the marine layer.

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Meteorologist Nick Mikulas
Severe event number one should start to ramp up this evening. This one looks like it’ll be quite loud for most at the very least. Here’s how I think it’ll play out.

Thursday evening/night….
What do I mean by a “loud” threat tonight? These storms will be packed with moisture, and more importantly, loaded with a deep layer of ice/hail aloft. That’ll make for plenty of friction, which means loads of lightning. With ample (elevated) instability, which we discussed yesterday, and plenty of wind shear, these storms will be able to stay strong to severe for several hours, bringing a widespread threat of loudness/thunder, as well as a threat for some scattered hail. Given the set up, I wouldn’t be stunned to see a golfball sized hail report, but most of the hail should be in the pea to quarter sized range. Hail is still going to be a relatively isolated issue since the whole storm won’t just be a hail fest, but garage the cars tonight if possible. Another thing to note is that the warmer air, and surface based instability will be in place for areas like Baton Rouge, New Orleans, and Lafayette. This means an isolated tornado or two will be possible down that way. That could nudge as far north as parts of St. Landry Parish, so be on the lookout in that area. Up here, it seems like the storms will develop a few hours ahead of the surge in moisture, so hail is by far our main threat. I’ll never rule anything out, but the set up doesn’t favor tornadoes across most of Central Louisiana. There will be supercells, but the airmass should be just cool enough at the surface to keep the tornado threat to our southeast. I will watch this closely, but please obey all warnings. You can’t rationalize with a tornado warning and say, “well, Nick said these storms would likely be elevated.” I mean, you could try I guess.

Monday evening through Tuesday….
This is still looking like a potential severe weather outbreak over a two day period from Texas through Louisiana and Mississippi. That doesn’t mean two straight days of severe weather, though it looks like we could see a few severe storms in our area as soon as Monday night. The main threat for us comes on Tuesday, as the intense upper level feature kind of stretches out, and slowly pivots through. Some models indicate this slowing will allow training of strong to severe thunderstorms over several hours, but that’s a detail that won’t be clear until a day or two before this arrives. What is clear is that severe parameters are forecast to be quite favorable for at least one, and perhaps two rounds of severe weather in our area. Large hail, damaging wind, and tornadoes will all be possible in this event, as well as the potential for flooding rain. It’s impossible to get too detailed just yet, as timing will shift, but models have been consistent for several days regarding the strength of this system. The details we need to figure out depend on what the Monday storms do to our local atmosphere, and the timing of all of this. But it definitely looks like a bumpy ride for us, and many areas around us. I’ll be updating daily until this arrives, then I’ll be in constant update mode.

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Its about that time of the year where shite gets WILD

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