We are continuing to watch the squall line as it continues moving East through the Mississippi Delta this morning. Before I go any further, I just want to say that although the models have handled this system well (we've been watching this timeframe for over a week), specific threat forecasts haven't held up with it so well. Monday, a significant tornado event was expected over the Plains and the Storm Prediction Center issued a "Moderate Risk". That forecast wound up being a "bust" as there wasn't a single tornado report that day (it happens to all of us though). Yesterday, strong tornadoes pounded Arkansas, especially the town of Clinton, where several homes and buildings were destroyed. Thankfully, initial reports say that there were no serious injuries. The point of me including this in the forecast discussion is to say that some systems we have a really good handle on, and some we don't, and this one falls in the latter category. With that being said, here is what we are expecting as we go through the rest of the day.
EARLY THIS MORNING: As I write this shortly after 6:00 AM, there are no severe weather watches or warnings as the squall line moves through the Delta. The temperature in Jackson is 70, while it's 52 in Greenville, so it's pretty easy to find the front. The squall line will continue to move Eastward and storms should stay below severe limits this morning.
OUR AREA: The latest model data remains inline with last night's thinking. We should see the first storms approach our Northwestern counties around 8:00 AM. From there, it appears that some discrete cells may have the potential to form ahead of the main squall line, and it's those discrete cells that have the best tornado potential, so we'll have to give them extra attention. The squall line will continue moving East throughout the morning, eventually getting towards Meridian around lunchtime. Between the possible cells ahead of the line, and the line itself, we are looking to be busy in the weather department through mid-afternoon when storms look to exit our West Alabama Counties then.
THREATS: The main threat will be damaging straight-line winds associated with the front. The tornado threat is marginal, with the best chances for tornadoes in any cells that form in front of the line, and in broken segments of the squall line. Heavy rain and flash flooding will also be an issue because as the line moves East, the individual storms in the line are moving from the Southwest to Northeast, so any particular area could see heavy rain sit over them for quite a while. Hail could also be an issue, but very large hail (like we saw a few weeks ago) is not expected.
VARIOUS THOUGHTS: The fact that the storms are not severe right now are very encouraging. However, with the slowing down of the line, that means storms will make it in here after the atmosphere has had some time to warm up and destabilize. Models are in pretty good agreement that CAPE (Convective Available Potential Energy) will be between 700-1200 J/kg, which is not overly impressive for April, but still plenty enough energy for storms to fire. Model soundings also show that wind will be increasing and turning with height, and that means that storms will be able to rotate. Basically, all of the ingredients for all modes of severe weather are there, now we really just have to wait and see what happens.
Make sure you have a way to get weather warnings today. The best way to do that is by having a NOAA Weather Radio or location-based smartphone app. We'll continue to have updates online, as well as the crawl system on the bottom of your TV, and cutting into programming as needed.