COLUMBIA, S.C. — This week, a series of dry, cold fronts will sweep across South Carolina, ushering in a significantly colder air mass. This frigid air will settle over the Southeast during the first half of the work week, bringing unseasonably cold temperatures through Wednesday.
Forecasts indicate low temperatures dipping into the mid-teens to lower 20s by Wednesday morning. However, confidence in the weather pattern decreases toward the weekend, as multiple systems could potentially impact the region.
Through Tonight
An unusually deep upper trough remains over the eastern CONUS, with a reinforcing shortwave trough moving in later tonight. We are expecting high temperatures in the upper 40s to lower 50s this afternoon.
A modified Arctic air mass from the Midwest is moving southeastward, accompanied by a vigorous mid-level shortwave trough. This feature will intensify near North Carolina later tonight, potentially generating a weak surface low in the Midlands.
Low-level warm advection and isentropic lift could increase moisture in the northern Midlands and Pee Dee, leading to light snow showers after midnight and before the sun rises Tuesday.
Accumulations are unlikely south of the North Carolina border, and warm soil temperatures reduce the chances of measurable snow. Overnight lows will drop into the middle to upper 20s.
Tuesday Through Wednesday Night
A robust Canadian high-pressure system will drive the region’s weather, starting near St. Louis and moving overhead Tuesday night. Despite abundant sunshine, cold air advection will keep temperatures well below normal, with daytime highs only reaching the lower to mid-40s—more typical of early December lows.
Ideal radiational cooling conditions will allow Tuesday night temperatures to plunge to the coldest levels of the week, between the mid-teens and lower 20s. While the likelihood of meeting cold weather advisory criteria remains low, residents should finalize cold-weather preparations. By Wednesday, daytime highs will warm slightly to the upper 40s to lower 50s, with overnight lows in the middle 30s.
Thursday Through Sunday
Thursday will see a brief warm-up with breezy conditions ahead of another dry frontal boundary. This front will deliver a fresh wave of cold, dry air on Friday, resulting in below-normal temperatures and another round of chilly nights.
By Saturday, high pressure shifts offshore, allowing moisture to increase and raising the possibility of showers late Saturday into Saturday night. While some models suggest cold air could return by daybreak Sunday, current forecasts lean toward rain rather than wintry precipitation.
Confidence in weekend weather remains low due to discrepancies between the GFS and ECMWF models, with the latter favoring a drier scenario. A second system may bring additional rain later in the weekend, but uncertainty persists.