Amid an unusually uncertain snow forecast, meteorologists are warning people to prepare for the possibility of a foot or two of snow in eastern Connecticut on Saturday, and local municipalities have begun storm preparations.

An update from the Connecticut Department of Emergency Services and Public Protection at 4 p.m. Thursday showed a forecast of 16 to 20 inches of snow east of roughly Essex, but noted a slight change in the track "will have a significant impact on snowfall amounts."

Similarly, AccuWeather said Thursday evening that "just a slight jog in the storm track could mean a difference between a 3 inch storm and a 12 inch storm."

"If the storm follows this track, we can expect a Nor'Easter (with possible blizzard conditions in eastern CT) starting before daybreak on Saturday and continuing until Saturday evening," the DESPP update said. "Northeast winds could gust to 50 - 60 MPH at times along the coast with temperatures in the upper teens and low 20's."

This could result in very low visibility for drivers and cancellations of most air travel in the Northeast. DESPP will send its next update at 9 a.m. Friday.

"It definitely will be a significant event," Gary Lessor, chief meteorologist with the Western Connecticut State University Connecticut Weather Center, said Thursday afternoon. "While exact numbers aren't a guarantee yet, there is a potential for 1 to 2 feet of snow, and wind gusts along the shoreline of 55 miles per hour, peak gusts."

Lessor expects the snow to start in the Groton-New London area before dawn on Saturday, ending somewhere between 10 p.m. Saturday and 4 a.m. Sunday. He said wind gusts could be sustained at 25 to 35 mph Saturday.

"With high winds (and) heavy snow, depending on where the heaviest bands set up, blizzard conditions are possible," Lessor said. He said it will be a fluffy snow, not a heavy, wet snow.

The National Weather Service has a winter storm watch in effect for New London County from Friday evening through Saturday evening. An update from 4:25 p.m. Thursday said total snow accumulations of 10 to 14 inches are possible, while another NWS map issued at 4:43 p.m. showed 12 to 18 inches for the region. NBC Connecticut meteorologists are forecasting 6 to 12 inches of snow for eastern Connecticut.

The U.S. Coast Guard warned of the potential of significant snowfall, minor to moderate coastal flooding, possible power outages, and offshore seas of 25 to 30 feet. The Coast Guard strongly advises boaters to not operate, and to double up on mooring lines.

Eversource said in a news release it's pre-positioning line and tree crews across the state.

"This storm has been tough to track, and we aren't leaving anything to chance," Steve Sullivan, president of Connecticut electric operations, said Thursday. "We have hundreds of crews flying in throughout the day today — and more arriving tomorrow — from southern and western parts of the country, so we don't have to wait for them to drive here."

Chris LaRose, general manager of Norwich Public Utilities, encourages customers to be prepared for the possibility of power outages between Friday afternoon and Sunday.

NPU urged customers to prepare a kit with a flashlight, batteries and first aid supplies; have alternative charging methods for phones and other critical devices; buy ice or freeze water-filled plastic containers to keep food cold; and fill up their cars with fuel.

The utilities are reminding customers to stay clear of downed wires and report them to 911.

Municipalities prepare

Some local cities and towns already have announced parking bans or restrictions, starting Friday evening or at midnight.

New London fire Chief Thomas Curcio, the city's emergency management director, said all three firehouses will have extra staff on duty and extra road salt has been ordered.

An update from the city said the New London Homeless Hospitality Center is at capacity, and those without shelter should go to the United Methodist Church at 130 Broad St., or the warming center at the Public Library of New London during business hours.

East Lyme police Chief Mike Finkelstein, also the town's emergency management director, said Thursday afternoon that this forecast "is probably one of the most uncertain I've ever seen," so he's waiting for firmer details but also preparing. He said the police and fire departments will have extra staff on hand.

Ledyard Mayor Fred Allyn III said the town has extra plow drivers on call, and public works crews are ready with tree removal equipment and chainsaws. "We're going to have continuous cleanup to deal with drifting snow, especially because it appears it will be kind of dry, so it will certainly be prone to drifting," he said. He added, "I think we're in pretty good shape."

Stonington First Selectwoman Danielle Chesebrough said she had a call Thursday morning with police, the Department of Public Works, town Human Services, IT and others, and they'll meet again Friday. She said if people lose heat, they can call the police department to be connected with Human Services for help.

City of Groton Mayor Keith Hedrick said Groton Utilities met Thursday afternoon, and there will be another meeting Friday at 11 a.m. He said officials are trying to get the latest information to determine exactly when to start pretreating the roads, since forecasts have been all over the place.

"It's a wide band, so we're trying to wait to get the most precise information, so that we're not wasting taxpayer money in plowing roads and reacting to the storm," he said, "but also appropriately reacting so that residents are safe during the storm."

e.moser@theday.com