CINCINNATI (AP) — Carson Palmer's near-perfect showing left San Diego out in the cold.

Palmer threw four touchdown passes in swirling snow -- two to Jerome Simpson -- and the Cincinnati Bengals snapped the Chargers' streak of four straight playoffs appearances with a 34-20 victory on Sunday that was an ending in several ways.

The Chargers (8-7) froze up in their coldest game in nearly three years, repeatedly self-destructing on a raw, windy evening. The loss gave the AFC West title to Kansas City, which beat Tennessee 34-14 earlier in the day.

This one will leave San Diego chilled to the bone for a long time.

The West Coast team was one of the league's best finishers, having won 20 of its last 21 games in December. The Chargers were out of their element Sunday -- and now, out of the playoffs as well.

"Words can't really explain how we feel right now," safety Eric Weddle said. "Our season is done. It's probably the worst feeling you can have."

The Bengals (4-11) are ending one of their worst seasons with a few satisfying moments.

Palmer, a Southern California kid, led them to their second straight win with a cast of reserve receivers. His 59-yard touchdown to Simpson -- playing in place of the injured Chad Ochocinco -- highlighted a 21-point fourth quarter against the league's top-ranked defense.

Palmer finished with a career-best passer rating of 157.2, just shy of a perfect 158.3. He completed 16 of 21 for 269 yards without an interception.

"That's the finest game that Carson has played here," said Marvin Lewis, who may have coached his final game in Cincinnati.

After losing 10 in a row, matching the club record for futility, the Bengals have won back-to-back games in front of small home crowds. No surprise there: Cincinnati has won 18 of its last 23 home finales.

The Chargers have a habit of finishing fast and winning titles. This time, they took too long to get started, forcing them to win out. They couldn't do it in the unaccustomed cold -- 29 degrees at the kickoff with a wind chill of 17. It was their coldest game since they dropped the AFC title game in New England at the end of the 2007 season.

The Chargers pretended they were plenty warm. Several came onto the field in blue shorts and sleeveless shirts for pregame warmups in a driving snow.

By the kickoff, they were well-chilled.

Receiver Vincent Jackson fumbled a handoff on a reverse on San Diego's opening play and had to chase it all the way back to the 1-yard line. The series ended with Mike Scifres shanking a 24-yard punt. Five plays later, Palmer threw a 3-yard touchdown pass to Jermaine Gresham.

It would be that kind of day for the team from southern California.

Philip Rivers came into the game with a career passing rating of 100 in December, the best in league history. He was 27 of 40 for 256 yards with a touchdown and an interception that set up one of the Bengals' fourth-quarter touchdowns.

"It's tough anytime you're eliminated from a chance of playing for the postseason," Rivers said. "It's something I haven't dealt with since I've been playing here. This was the final straw."

Palmer, who won the 2002 Heisman Trophy at USC, has been throwing to a much different group of receivers the last two games. Terrell Owens is recovering from knee surgery, and Ochocinco was inactive Sunday with a bad ankle.

Simpson, a second-round pick in 2008, had a career-high six catches for 124 yards. Andre Caldwell had four catches for 87 yards, and Gresham had four for 56 yards and a touchdown.

Without Owens and Ochocinco -- the self-described Batman and Robin -- the passing game was super.

"They ran great routes and made big plays," Palmer said. "They made some of the biggest plays we've had all season."