It was a winter storm advisory, but late Thursday afternoon the National Weather Service in Wilmington took another look to the west and upgraded it to a warning.

A winter storm warning is issued by forecasters when severe winter weather conditions are imminent and will definitely have an impact on whether drivers can get to where they want to go.

Snow began falling in Portsmouth by 4:30 p.m. Thursday. It was expected to change to sleet and freezing rain.

Moreover, the precipitation is expected to change over to rain during part of the day Friday, then switch back to snow Friday night and on into early Saturday morning.

"Anyone who has to travel should use extreme caution. It sounds as though roadways will be treacherous," said Kim Carver, director of the Scioto County Emergency Management Agency. "But people should stay in. They can call ahead to see if appointments and meetings have been canceled."

Drivers should not use cruise control and should make no abrupt starts or stops, said Trooper Todd Crabtree, spokesman for the Ohio State Highway Patrol Post 73 at Portsmouth.

"They need to start slowing down well before reaching a bridge or a curve, not wait until they're right on them," Crabtree said. "And they want to keep a safe distance between their vehicle and the car ahead of them"

His advice was for people to get their supplies in early and run their errands before the storm hits, or worsens.

"On ice, even four-wheel-drive vehicles can skid and slide off the road," Carver said. "Road crews as usual will be treating streets and highways, but sometimes the precipitation can be so heavy in these winter storm events that it's tough to keep then clear."

Scioto County Engineer Clyde Willis sent workers home at 4 p.m Thursday with the possibility they could be called to return to work during the evening and night.

"They've worked all day and we didn't want them sitting around here until the snow starts, since we don't know what time that will be," the engineer said.

He said the county has plenty of road salt on hand, stored at four different locations around the county.

Crews from the Ohio Department of Transportation District 9 headquarters in Chillicothe had been dispatched by 4:30 p.m. to begin treating state and federal highways for snow and ice, reported Kathleen Fuller, public information officer for ODOT.

The icy conditions Thursday evening brought with it a string of fender-benders.

Among the agencies kept busy investigating mishaps were the Portsmouth post of the Ohio State Highway Patrol, reporting at least four wrecks, the Portsmouth Police Department with at least two accidents, and the same number filed by the Greenup County Sheriff's Office.

No serious accidents or injuries were reported by any of the agencies at press time.

Frank Lewis contributed to this story. G. SAM PIATT can be reached at (740) 353-3101, ext. 236.