Severe Threat Latest:
Overall, there were minimal changes in the latest severe outlook for today. The Storm Prediction Center continued to keep our counties hugging the Mississippi River under a level 4 Moderate risk, leaving the remaining counties under a level 3 Enhanced Risk.
A couple of things remain uncertain regarding today’s potential for severe weather. Unlike the significant event that transpired this past Friday, storms will have to deal with a warm layer of air roughly 5,000 feet in the air, something we call the “cap”. As we discussed yesterday, when you a “cap” in place, this limits the maturing process for thunderstorms.
Secondly, we’ll need to pay attention to just how far north a warm front will be able to lift into northern Illinois or southern Wisconsin. Forecast models this morning came into agreement that the warm front will end up somewhere around interstate 80 this afternoon, leaving the more explosive and volatile environment to the south. This would keep our winds out of the east off of Lake Michigan, resulting in a downward trend in our severe potential. But should the front make it towards the IL/WI border, our severe threat goes up.
Timing Out The Storms:
Before we dive into the timing, I would just like to point out why it is important for keep an eye on model trends leading up to such an event. The past few days, hi-res models were set on a round of strong to severe storms initiating early in the afternoon in northeast Missouri, tracking northeast into areas south of highway 20 between 5PM to 8PM. This morning, they are coming in with a much different story, bringing in two rounds of storms.
The first arrives either late in the morning into mid-day, with the second round tracking through Northwest/North central Illinois this evening into early tonight. Now, should any storms develop, all hazards will be on the table including damaging straight-line winds, large hail, heavy rainfall, and even a few tornadoes. However, as previously mentioned, this will all be dependent on how long the “cap” can hold and where the warm front will end up. But just make sure that you’re “weather ready” by having multiple ways to get watches and warning, and by having that severe weather shelter and kit ready to go.
Wednesday’s Severe Threat:
Wednesday morning will also be a time frame to be “weather ready”. Something to definitely keep in mind for the early-day drive. Ahead of a strong cold front, forecast models show a line of strong to severe storms developing to our west.
With time, this line will move east, bringing the potential for damaging straight-line winds, frequent cloud to ground lightning, and a tornado or two. This line should be out of our area by mid to late-morning, with clouds decreasing into the afternoon. Highs will be achieved early in the day, with temperatures sitting in the 50s Wednesday afternoon.