An unseasonably warm stretch of weather is forecast before strong storms bring the risk of damaging winds and a substantial cooldown by midweek.
Surface analysis Monday shows an organizing area of low pressure near the Four Corners region of the Southwestern U.S. Over the next 24 hours, this low pressure is forecast to become better organized, producing the risk of severe storms along the Texas Gulf Coast and heavy snow in the North Texas Panhandle. A warm front will approach the southern Midlands and Lowcountry Wednesday as the low pulls away from the Lower Mississippi River Valley and into the Tennessee River Valley. This will introduce a warm and unstable environment and could result in strong and severe thunderstorms.
High-resolution weather models indicate the most instability will be found across the Midlands, Lowcountry, and Pee Dee. As a warm front lifts north, a few strong storms will be possible during the pre-dawn hours Wednesday across the Midlands and Upstate. This first round will likely be limited in severity because it will come through before daytime heating destabilizes the atmosphere. The main line of strong storms associated with the approaching cold front will enter the Palmetto State by late Wednesday morning. Storms will push east by midday, with a broken line of strong storms possible along the I-77 corridor from Rock Hill to Columbia. The cold front will push storms toward the coast by the early evening hours Wednesday. Model guidance is in agreement that storms should diminish in coverage and intensity by midnight Thursday.
The Storm Prediction Center has a "marginal" risk for severe weather across the Midlands, Lowcountry, and Pee Dee. This classification represents a 1 on a severe weather scale of 1-to-5 and means that a few isolated severe thunderstorms are possible. The atmosphere will support the risk of damaging winds of up to 60 miles per hour. The upper-level wind pattern does also suggest a few tornadoes are also going to be a possibility.
There is the potential for watches and warnings to be issued through Wednesday. If a watch is issued, it means that the ingredients for severe weather or tornadoes are present in the atmosphere. Watches are typically issued before the weather turns severe and tend to cover a fairly large geographic area for several hours. A warning on the other hand is issued when severe weather is ongoing for a specific location and is typically on a smaller geographic scale, typically covering only a few counties at a time. Warnings generally last an hour or less in any given location. Residents are encouraged to have multiple ways to receive severe weather alerts and to keep a close eye on the forecast over the next 24 hours.