Washington County Hospital spokeswoman Maureen Theriault said Chalfant was pronounced dead Saturday at the facility. She said she could not make any additional comments.
Chalfant, guitarist for the blues band Rudy and the Bluefish, was traveling north on Md. 64 near the intersection with Bradbury Road on Jan. 18 at 12:46 p.m. when his 2000 Chrysler hit an icy patch and left the road, Maryland State Police said.
Chalfant's car struck a guardrail, overturned and landed in a creek bed, police said.
Rudy and the Bluefish drummer Mike Holtzman said Chalfant was on his way home from a show the night before. Chalfant, like others in the band, routinely spent the night in Leesburg, Va., after late Saturday evening shows because of safety concerns about driving late at night, he said.
He said Chalfant was by far the most safety-conscious member of the group.
Chalfant, a Waynesboro, Pa., native, was a fixture in the Hagerstown blues music scene for about 30 years. He was known for playing with bands including Kartune City, Dem Guise and The Shift.
Rudy and the Bluefish was a big draw at area bars and special events such as the Western Maryland Blues Fest and the annual Summer Bash benefit concerts.
Area musicians on Sunday spoke highly of Chalfant's musical ability and personality.
Carl Disque, a saxophone player and founder of the Western Maryland Blues Fest, said he encountered Chalfant a decade ago during an impromptu performance at Oliver's Pub. Disque said he was immediately impressed by Chalfant's ability and was surprised by how nice he was.
"I said 'Jason, you really need to start playing out,'" Disque said. "A lot of guitarists are really egomaniacs. He certainly wasn't. That's the highest compliment you can give someone, that they have talent, yet they're so down- to-earth."
Lana Spence, a Hagerstown-based singer-songwriter, has been friends with Chalfant since he began playing music with her brother more than 25 years ago. Spence said Chalfant was always a "shy, but super-nice" guy who put almost all of his emotions into playing his guitar.
"He was a really good player, like jaw-dropping for other guitarists," Spence said. "It was all feel. It just pours out of his fingers. Musically, he was one of the best guitarists in the area and out of the area."
Lancaster echoed the sentiment, saying Chalfant was the only person who was able to get a good sound out of a Gibson SG Standard that Lancaster owned. Lancaster lent the guitar to Chalfant during a show in which Chalfant's guitar was not working.
"He made that thing sing like I never heard," Lancaster said. "I was like ... that's what it's supposed to sound like."
Arnie Helmick, bassist for Koko Blue, said he did not know Chalfant well, but jammed with him on a few occasions. He said Chalfant was among the most humble and talented people with whom he has played.
"He knew how to share a stage with people. There was no arrogance," Helmick said.
Helmick and several other musicians said they were shocked at the downturn of Chalfant's condition over the weekend, especially after he appeared to be improving just days earlier.
Jimmy Chalfant, Jason Chalfant's younger brother and former drummer for the rock band Kix, said last week that his brother received head injuries and a broken arm. He said his brother had been in a coma since the crash.
Hospital staff members told the family Wednesday that Jason Chalfant was improving, Jimmy Chalfant had said. A spokeswoman said Wednesday that his condition was upgraded from critical to serious.
Attempts to reach members of the Chalfant family Sunday evening were unsuccessful.