Video: Bills vs. 49ers Under Snow Warning; 2-3 Feet in NFL Week 13 Weather Forecast

The National Weather Service has extended its "lake effect snow warning" in Buffalo through Monday at 7 p.m. ET, with potentially 2-3 feet of additional snow accumulations in the area.

The Bills are currently scheduled to host the San Francisco 49ers on Sunday Night Football at 8:20 p.m. ET.

"Whiteout conditions are expected and will make travel treacherous and potentially dangerous," the NWS said in its alert. "Travel will be very difficult to impossible within the heaviest portion of the lake effect snowband."

The expectation for Sunday is that the game will be held as scheduled despite the potential blizzard conditions.

"This is going to be concerning for people trying to travel to the football game. We do not expect the game to be postponed or anything like that. The game will go on," Erie County executive Mark Poloncarz told reporters Friday. "Now, we've had games that are colder than that. Just got to dress appropriately. So people need to be prepared. It's the first real cold of the season. We haven't had anything like this all year."

Buffalo is no stranger to major winter weather systems or potential game delays. A January Wild Card matchup between the Bills and Pittsburgh Steelers was delayed by one day last season due to driving bans during a storm, while two years ago, a home game against the Cleveland Browns had to be played in Detroit instead.

"We're trying to stay on top of it," Bills head coach Sean McDermott told reporters on Friday. "You guys know things change around here quickly with the weather coming off the lake and everything. So do the best we can."

As for the game itself, the Bills (9-2) would already clinch their fifth straight AFC East title with a win, while the 49ers (5-6) are fighting for their playoff lives but will be doing so without edge-rusher Nick Bosa, offensive tackle Trent Williams, linebacker Dre Greenlaw and cornerback Deommodore Lenoir due to injuries, per head coach Kyle Shanahan.

Quarterback Brock Purdy is questionable.