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

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Meteorologist Nick Mikulas
We have two potential severe events on the way, with one possibly bringing significant severe weather, so let’s get right to it.

7:00 PM Thursday until 4:00 AM Friday…
SPC has us in a slight, level 2 of 5 risk for severe weather Thursday evening into early Friday morning. We will have something known as elevated instability with this round of storms. I’m going to try and simplify elevated instability now. Pray for me. This means that a parcel of air lifted from the surface would not be unstable. Surface based instability is needed for the development of tornadoes, and in most cases, severe wind gusts. Severe wind gusts are still possible with “elevated storms”, but it’s not as likely. A cool layer of air near the surface will keep that air stable Thursday evening and night. Air parcels lifted from about 6000-7000 feet up, will be unstable. What this means for us, is that there is a threat for hail, and that’s about it, since the cloud base will be elevated by several thousand feet. There’s your brief, and still somewhat complex explanation. Meteorology really is a fascinating thing when you dig in. It’s also cool just to look at the sky, so there’s something for everyone! Along with these potential hail producers, we will see a general 1/2 to 1 inch of rain. This doesn’t jump out as a system that will produce widespread, or massive hail, but some scattered pea to quarter sized hail is possible.

Late Monday into Tuesday, March 21-22…
Models are a bit faster on this system, but still look very impressive. It’s possible we see storms as soon as Monday night, but at this point, I think Tuesday is the main event in our area. SPC currently has a 15% risk for severe weather in our area, but I expect that to increase in the next few days as model agreement on the strength of this system has been very good. This would be an all modes of severe weather event, with the potential for 2-4 inches of rain, and isolated higher totals. Timing, and any Monday night storms could change the atmosphere, so it’s impossible to get detailed yet. It does look like this will easily be our most significant severe weather threat so far this year. It’s never time to panic, but it’s time to kind of figure out what you’ll do should you find yourself in a tornado warning. Where is the interior room in your house that puts as many walls between you and the outside? If you live in a camper or mobile home, where will you evacuate? How will you make sure you have an up to the minute source for warnings? Remember, being informed is the best defense against these threats, and while I’ll be pumping out too much information, it’s really hard to hit every warning as it happens. I’ll be posting every day until the threat is clear.

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