As Massachusetts prepares for the fourth major winter storm in three weeks, forecasters have adjusted snowfall totals and the timeline for Wednesday’s storm already dubbed the “four’easter.”
Snow is expected to start falling around the evening rush hour in the Boston area, and could potentially bring 6 to 8 inches to the region by the time it ends on Thursday, said Eleanor Vallier-Talbot, a meteorologist with the National Weather Service.
“The storm’s track is going a little farther south,” she said Tuesday night.
Earlier, the service had predicted the snow would start in mid-afternoon, and bring totals of 6 to 10 inches.
The Wednesday evening commute “looks to be impacted with heavy snow especially south” of the Massachusetts Turnpike, the service advised on Twitter.
The Plymouth area is still predicted to get about 6 to 10 inches of heavy, wet snow because temperatures will hover around freezing, and winds will be from 20 to 25 miles per hour, with gusts of up to 45 miles per hour, Vallier-Talbot said.
“Temperature is going to be a big, big determining factor as to how heavy the snow is going to be and whether it could even mix with rain,” she said.
Snowfall is expected to be heaviest in the Boston area Wednesday night, tapering off Thursday morning and ending around noon, but perhaps leaving flurries that linger into the day, she said.
The service issued a storm warning from 8 a.m. Wednesday to 8 a.m. Thursday for eastern Massachusetts, including Boston, Plymouth and the Cape.
The expected winds of 25 to 30 miles per hour will be less intense than those experienced during last week’s nor’easter but still could cause damage, the service said.
The storm prompted the Boston Public Schools to cancel after-school activities Wednesday, Mayor Martin J. Walsh announced.
The city has up to 800 pieces of equipment and over 28,000 tons of salt on hand, ready to pre-treat and plow streets from Wednesday into Thursday, Walsh said.
“Today may be the first day of spring, but the City is still prepared to keep our streets, residents, and students safe during this snowstorm,” Walsh said in a statement.
The Massachusetts Emergency Management Agency cautioned in a bulletin Tuesday that heavy snow and high winds could cause electrical outages in Eastern Massachusetts.
There also is a risk of coastal flooding from Cohasset and Scituate southward to Cape Cod and the Islands, according to Vallier-Talbot.
Western Massachusetts could see 1 to 4 inches of snow, with 3 to 4 inches expected for Springfield, according to the weather service.
Ahead of the storm, the state Department of Transportation said Tuesday that crews were pretreating roads with brine and magnesium chloride and planning the deployment of spreaders, plows, and maintenance equipment.
MassDOT cautioned that falling snow and high winds could reduce visibility and asked drivers to be careful, minimize distractions, and always wear seatbelts.
“We are hoping that travelers will look at where they plan to go and check the forecast for that particular area as driving could be hazardous at various times,” Highway Administrator Jonathan Gulliver said in a statement.
“There will be heavy snowfall in some areas and the timing of the storm will differ from region to region,” Gulliver continued. “We encourage members of the public to monitor the weather, plan ahead if they will be traveling and plan extra time to reach destinations whether they are in a vehicle or using mass transit.”
The MBTA is also preparing for the storm and will run trains overnight Wednesday into Thursday to help clear ice and snow from tracks, as well as keep emergency crews on standby to address any weather damage, it said in a statement.
The T expects to offer regular service on ferries and rail lines.Correspondent Jeremy C. Fox and Sean Smyth of the Globe Staff contributed. Alana Levene can be reached at email@example.com.