RALEIGH — On the heels an unseasonably warm weekend, the Triangle began girding for snow Thursday night.

A dense fog shrouded the area Wednesday as temperatures that reached into the 70s over the weekend began to fall, but the National Weather Service at Raleigh Durham International Airport said the rain and fog would move through the Carolinas on Wednesday night and drop temperatures to a low of 48.

As temperatures continue to drop Thursday, the rain is expected to turn into a wintry mix about 7 p.m., and accumulate one to three inches in grassy areas overnight, according to WTVD Chief Meteorologist Chris Hohmann.

“There is a strong chance for nighttime accumulation in elevated and grassy areas Thursday night, stopping around midnight,” Hohmann said. “It’s going to be a quick-hitting system.”

The snow could melt quickly on roads then freeze overnight, causing black ice for a dangerous Friday morning commute.

The snow should end early Friday morning and give way to clear skies through the weekend with temperatures in the 50s during the day and falling to around 30 at night.

Among the counties expected to be affected are Wake, Franklin, Durham, Orange and Chatham.