Gov. Charlie Baker is strongly urging people to stay off Massachusetts' roadways during Saturday's storm.
Baker said the rate of snowfall is expected to pick up in the Bay State between 9 and 10 a.m., and to remain as high as two to four inches per hour through 4 p.m.
"This is going to be a very big storm," Baker said. "Probably one of the biggest we've experienced in the last few years."
Tractor-trailers are prohibited from driving in Massachusetts from 6 a.m. until midnight.
"Can't have trucks jackknifing and shutting down roads during conditions like this," Baker said. "Crews can't clear the snow when that happens, and anyone else out there is put at serious risk of being stranded."
The governor did not issue a travel ban for all vehicles, but repeatedly and strongly recommended that everyone avoid any nonessential travel.
"We're urging everyone, to the extent possible, to stay home tonight and tomorrow," he said.
Baker encouraged people to get takeout from their favorite restaurants Friday night to support them ahead of the storm.
"The high rate of snowfall tomorrow means it will be especially challenging for crews to clear the roads, especially during that period in the middle of the day and toward the end of the day," Baker said, "which makes it especially important that people — and I'm going to say it again — to the fullest extent possible, stay off the roads, so that the crews have the room that they need to do their work."
"Have I made myself clear on staying off the roads tomorrow?" he added.
The Massachusetts Department of Transportation expects to have up to 4,000 pieces of equipment out Saturday.
"Travel will be very difficult tomorrow, especially in southeastern Massachusetts and on the Cape," said Jonathan Gulliver, the highway administrator for MassDOT. "We are expecting an intense rate of snowfall and high winds that will reduce visibility and lead to some hazardous and blizzard-like conditions in some areas throughout the day tomorrow."
The MBTA will be running trains equipped with snowplows and ice-cutters Saturday to keep the tracks clear, according to General Manager Steve Poftak.
"We will be suspending the D Branch of the Green Line at the end of service tonight, and we will not run any train service on the D Branch for the entire day tomorrow," Poftak said. "However, we will have replacement bus service available that will run from Riverside to Kenmore."
Train service on the Mattapan Line will also be replaced by buses, Poftak said. There will be no ferry service Saturday.
Residents and officials across Massachusetts and the rest of New England are bracing for a powerful winter storm expected to produce blizzard conditions Saturday.
Snow is expected to begin falling late Friday evening. The system will then intensify as a nor’easter and bring snowy conditions with localized snowfall totals of up to two feet or more and wind gusts of 50 to 60 mph.
Boston Mayor Michelle Wu and other local officials on Friday rushed to declare snow emergencies and impose parking bans, warning that wind-blown snow could make travel nearly impossible and colder temperatures could mean dangerous wind chills after the storm passes Saturday night.
The Associated Press contributed to this report.