SAN FRANCISCO (AP) — San Franciscans bared an unusual amount of skin for this time of year Tuesday, as a city better known for its chilly summers, drizzle, and fog is seeing its hottest March in at least two decades, part of a rare winter heat wave baking the U.S. West.

While the Bay Area flirts with nearly 90 degree (32.2 C) highs, Phoenix is expected to top 100 F (37.7 C) this week — something it usually does in early May and has never done before March 26 — and Las Vegas could also see its earliest ever triple-digit temperature in the coming days.

Meanwhile, the Midwest and eastern half of the country are digging out after powerful snow storms that led to thousands of flight cancellations this week.

Dogs and sunbathers flocked to Crissy Field on the north end of San Francisco, as the Golden Gate Bridge shimmered nearby.

“It feels like summer already in March. That’s crazy, but I love it,” said dog walker Justyce Roliz. “The dogs, they love running in the water. They love to cool off. They’re loving it.”

Resident Jessica Ling said the hot weather was a nice surprise, “but it’s difficult because we don’t have AC in our house. So we have our fans going, our windows open, but we try to be outside as much as we can.”

Records across the Bay Area toppled Monday and highs Tuesday were projected to climb even higher. San Francisco International Airport hit 83 F (28.3 C) Monday, while Silicon Valley’s Redwood City reached 90 F (32.2 C), breaking records set in 2004. San Jose reached 85 F (29.4 C), tying a record set in 1914.

It’s unusual for San Francisco to get this hot this early, but not unheard of, said Roger Gass, a meteorologist with the National Weather Service in the Bay Area. It last happened in 2005, when downtown hit a record 87 F (30.5 C) on March 11, part of a two-day heat wave and its record high for the month.

Las Vegas could reach between 94 and 98 F (34.4 and 36.6 C) over the next few days with a chance temperatures could reach 100 F (37.7 C) Saturday, which would be the earliest Las Vegas has reached triple digits. The record high for March is 93 F (34 C), set back in 2022.

Weather forecasters in Arizona issued extreme heat warnings for areas in Grand Canyon National Park, cautioning visitors to avoid strenuous activities during the hottest parts of the day. Meanwhile, in Colorado, the heat wave continues at the end of an unusually warm winter that has resulted in a lack of snow, affecting water supplies.