LEWISTON — Get ready for another blast of snow and wind.

“We saw part one on Thursday,” National Weather Service meteorologist John Cannon said Friday. “Part two is happening right now. Part three comes Saturday.”

By Saturday afternoon, a storm that already passed over Maine once plans to pivot over Halifax, Nova Scotia, and hit the state again, a maneuver weather professionals call “retrograde.”

“It’s very rare,” Cannon said. “I’ve never seen any storm turn back that far during the winter. It’s a very intense storm.”

So far, accumulations on the first two parts have been light, dropping fewer than six inches total in most local areas. Saturday’s conclusion will bring the storm to a crescendo in the afternoon and evening — with rapidly accumulating snow, and gusts of wind that could hit 50 miles per hour, he said.

A winter storm watch is in effect for the whole region until Sunday evening. Snow drifts and power outages are likely, Cannon said.

Total accumulation for the long holiday weekend could hit a foot, but details were uncertain Friday night.

“This storm is just forming,” Cannon said.

It is likely to be over by Sunday afternoon, giving people a little time to dig out before the start of the decade’s first work week.

In Lewiston-Auburn, emergency parking bans are in place. Lewiston’s ban extends until 7 a.m. Monday. Auburn’s ban is scheduled to end at 8 a.m. Saturday, before the weekend’s worst weather.

By Friday night, local emergency officials had seen some accidents but none were life-threatening. People are encouraged to stay off the roads if possible.

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