A potent storm system will be rolling out of the Plains as we head through Sunday. The storm system is clearly identifiable on water vapor imagery with a large swirl noted near the Panhandles of Texas/Oklahoma. This storm system will be drawing warm, moisture rich air northward through the Mississippi Valley and into the Southeast, Tennessee and Ohio Valleys, too.
While temperatures are still cool this morning, they will be continually rising through the evening hours and for many east of the Mississippi river into the early morning hours, Monday. Temperatures will make it close to 60 degrees as far north as the Ohio river before the storm system passes with a cold front dropping temperatures behind it. Further south, temperatures will climb into the mid 70s from Louisiana across the southern half of Mississippi and into southern Alabama. While north of I-80 it will continue to feel like winter with temperatures in 20s and 30s.
This sets up a perfect, ripe environment for thunderstorms and severe thunderstorms to develop. Development will likely be slow to occur and likely won't begin until 6-8 pm from St. Louis southward through eastern Arkansas and southwestward into extreme northeastern Texas. While the development make take a while to begin, once it does I anticipate storms to build rapidly. Storms will have the threat of become severe from the south tip of Lake Michigan all the way to the Gulf Coast with a "Moderate" risk of severe thunderstorms from southern Illinois southward through the Mid-South and into northern Mississippi and northwestern Alabama.
The "Moderate" risk area will also be the most likely area that tornadoes could develop with highest risk for tornadoes occurring from eastern Arkansas through northern Mississippi and the Mid-South and into northwest Alabama. The movie below shows the highest potential shaded in orange.
Here is the general thought on a timeline for this event:
8 PM (St. Louis, Jonesboro, Pinebluff)
Midnight (Chicago, Paducah, Jackson, TN, Tupelo)
3 AM (Louisville, Nashville, Huntsville)
6 AM (Cleveland, Lexington, Chattanooga, Birmingham)
Be prepared for any potential severe weather. Make sure you have ways to be notified of impending severe weather. I highly recommend WeatherCall as the source you should depend on for your weather alerts and warnings. For a minimal fee it will contact you only when a warning is issued for your location so you don't have to worry about being awoken or alarmed by the weather radio for storms miles away. As a meteorologist, I would not recommend a weather safety product unless I was convinced it is a life saver. After the tornadoes of 2011 it became evident on just how life saving WeatherCall is. (Learn more about WeatherCall)
Additionally, after living through the tornadoes that impacted northern Alabama last Spring and left us in the dark for days, I recommend an emergency crank radio that will keep you informed even with the power is out. This is the one I purchased for my family and recommend to you. It is manufactured by Midland who is the name to buy for weather radios.