The National Weather Service’s Charleston office warns residents to brace for a rare winter weather event this weekend, with snow likely Saturday afternoon through Sunday morning.

Rain and snow will begin mixing Saturday, Jan. 31, before transitioning entirely to snow after 4 p.m., according to the seven-day forecast. The snowy conditions will persist through mid-day Sunday, Feb. 1.

The Weather Service cautions that “considerable uncertainty” remains about the exact timing and amount of snowfall. Snow could begin anywhere from 9 a.m. to 3 p.m. Saturday.

Travel conditions might get dicey as the weather progresses, and the Weather Service is warning of potentially slick roadways and bridges.

Temperatures will plummet Saturday night to 21 degrees, with wind chills dropping to just 8 degrees early Sunday morning. The Weather Service expects to issue an “Extreme Cold Watch/Warning” for those conditions.

Snowfall in Charleston remains exceptionally rare. Data from Charleston International Airport shows accumulating snow twice in successive years hasn’t occurred in decades, making this weekend’s forecast particularly unusual for Lowcountry residents.

The frigid conditions won’t last long. Temperatures are expected to climb back to 55 degrees by Feb. 4, returning Charleston to more typical winter weather patterns.

The last significant snowfall in Charleston occurred in recent years, but back-to-back winter weather events represent an anomaly for the typically mild coastal climate.