Located near the Black Sea, the Alpine resort of Rosa Khutor that will host the skiing races at the Olympics is known for varying weather conditions.
"Sochi can be challenging with the weather and everything," U.S. Alpine director Patrick Riml said. "So she ]Shiffrin] showed today that she's very well prepared."
The 18-year-old Shiffrin led by 0.03 seconds after the opening run and ending up winning by 0.13 ahead of Maria Pietilae-Holmner of Sweden for the sixth victory of her career.
With all six of her wins in slalom Shiffrin took over sole possession of second on the all-time slalom list among American women, trailing only Tamara McKinney's nine victories.
Nastasia Noens of France moved up from 13th after the first run to finish third, 0.62 behind.
Shiffrin was 12th and second in her previous two slaloms and was clearly motivated for this race.
"I was really psyched to win again," she said. "It's been a fight all season and I feel like, if I'm not perfectly ready, then the win goes to somebody else. So I was really trying to prepare myself and be ready to go today no matter what the conditions or the visibility."
Bobsled driver Steven Holcomb didn't win a medal. But at least he didn't crash, either.
The Park City native and his crew on the "Night Train 2" sled, including Alpine's Chris Fogt, finished a relieved seventh in a World Cup four-man race at Winterberg, Germany on Sunday, after crashing twice on the course earlier in the week once in training, and once in another four-man race Saturday.
"It's been a challenge this week to say the least," U.S. coach Brian Shimer said. "It's good to get a reality check and to know the rest of the world isn't going to roll over and let us take the prize. It's going to be a battle, and we'll be prepared for it. We knew this would be the worst stop on tour for us, so we'll lick our wounds and move on."
Holcomb finished in a two-run combined time of 1 minute, 51.03 seconds 0.01 seconds out of sixth place and 0.94 seconds behind winner of Germany's Maximillian Arndt. The rough weekend snapped his streak of winning the first seven races of the season.