Legions of storm-weary commuters Tuesday were left fuming in gridlocked traffic or shivering on train platforms amid an unprecedented level of breakdowns as the MBTA’s top official warned that the hobbled transit system may not return to normal for a week.
About 40 percent of all Red and Orange Line cars were disabled for mechanical problems, the highest percentage in memory. “We haven’t had anything like this,” said Beverly Scott, general manager of the Massachusetts Bay Transportation Authority. One inbound Greenbush commuter train was disabled on the tracks near Quincy Center for nearly two hours.
“It was going from one disaster to another disaster, and nobody knew what to do,” said Chris Kane, of Hanover, a passenger on the stranded Greenbush train.
The disruption — caused by a combination of extreme weather and aging infrastructure — means that the system will run well below capacity for Wednesday’s Super Bowl parade, said Scott . “It’s not a question of being unprepared,’’ she said. “There is no magic dust that you can put on it.”
Governor Charlie Baker blasted the MBTA’s performance and said he would soon meet with Scott and Transportation Secretary Stephanie Pollack to discuss ways to improve service.
“It’s unacceptable for commuters to experience these delays, but we ask everyone to be patient and plan ahead,’’ Baker said.
Boston has experienced its snowiest week in over a century, according to National Weather Service records, with more snow expected later this week.
Service on public transit remained sluggish during the evening commute, and traffic in many places was at a standstill. Around Massachusetts General Hospital, the backup was so bad that officials asked employees who could not walk or take public transportation to stay at the hospital to ease congestion and “ensure proper staffing levels.”
Officials said commuters could face delays for days. With throngs expected to take trains to Boston for Wednesday’s parade, the city’s parking ban lifted, and school buses returning to narrowed roads, getting around was expected to be a challenge.
Scott said she hoped to boost the number of trains for the New England Patriots victory parade, which is expected to bring tens of thousands of fans into Boston, but that the system would not be close to full strength.
“I will not put out equipment that, in many instances, I do not think I can run safely,” she said.
Baker noted that some subway trains date back to the infamous Blizzard of 1978. At the same time, the more recent one-two punch of a historic blizzard and major storm was highly unusual. The two storms dumped more than 40 inches of snow on the area, more than any seven-day stretch in more than a century.
“This is not just a harsh winter,” he said. “It’s the largest and most significant snowstorm ever, over the course of the past 10 days in Greater Boston, combined with a significant amount of Arctic-like temperatures.”
The bitter cold is expected to linger for the next few days, forecasters said, and more snow could arrive Thursday. On Wednesday, temperatures should warm to the mid-20s for the Patriots parade, but the wind chill should be in the teens. “It’s still going to be a cold parade,” said Glenn Field, a National Weather Service meteorologist, “but significantly better than Tuesday.”
Mayor Martin J. Walsh of Boston said the victory parade, initially scheduled for Tuesday, couldn’t be postponed until the weekend, so it would proceed despite the weather and the transit woes. The duck boat parade is slated to start around 11 a.m. at the Prudential Center and end at City Hall Plaza.
The amphibious vehicles might well move faster than traffic did Tuesday morning, when it took some drivers almost 35 minutes on the Massachusetts Turnpike to get from the Boston University Bridge to South Boston, a drive that usually takes less than five minutes.
The afternoon was no better.
Around 4:30 p.m., State Police warned commuters to avoid Storrow and Memorial drives altogether, and closed an exit off Interstate 93 to Government Center, to divert the flow of cars.
The delays fell heavy on commuters already weary from a week of shoveling and numbing cold.
In Charlestown, the line for the Orange line was four deep, and the signs that typically display arrival times were blank. The voice on the loudspeaker repeatedly announced delays.
Desperate times called for desperate measures. K.C. Erickson, 25, decided to take an outbound train for two stops in hopes of catching a less-crowded ride into the city. He said he wasn’t surprised by the delays, given the circumstances.
“It’s a pretty crazy amount of snow, so I guess you can’t blame [the MBTA] too much.”
Others were less charitable. Chris Myers, 50, of Malden, was at his wits’ end.
“I’ve been waiting here for 50 minutes,” he said. “In the cold, when the weather is like this, it’s bad. But even on a regular day it’s horrible.”
Two trains came, but were too crowded for him to get on.
On the Red Line, Mark Lamberti had prepared himself for a wait. But not this.
“I knew the commute was going to be pretty bad,” he said. “I didn’t know it was going to be like that.”
At the Revere Beach station on the Blue Line, passengers huddled in a waiting area above the train platform. Ernest Imafidon of Revere said delays — and winter storms — were becoming all too familiar.
“I was like, ‘Not again,’ ” he said.
Just before 8 p.m. Tuesday, an E branch Green Line train was involved in an accident with a vehicle near the Brigham Circle station, shutting down service between the Heath Street and Brigham Circle stations for about half an hour, according to Joe Pesaturo, spokesman for the MBTA. He said there were no injuries.
On the commuter rail, problems included a 100-minute delay on the Fitchburg/South Acton line and a 120-minute delay on the Needham line. Some trains on the Newburyport/Rockport line were canceled.
Sue McGrath rode a Greenbush line train from the South Shore that took almost three hours to get to South Station, instead of the usual hour. McGrath said the toilets were overflowing in the bathrooms and passengers didn’t know what to do.
“You’re just stuck,” she said. “We were like hostages.”
Globe correspondents Aneri Pattani and M.G. Lee, and David Scharfenberg, John R. Ellement, Andrew Ryan, Nicole Dungca, Andrew Ba Tran, Laura Crimaldi, and Steve Annear of the Globe staff contributed to this article.