NASCAR Cup Series races don’t often have to deal with blizzard warnings. Neither does San Bernardino County, Calif. Both could be impacted over the weekend.

The Pala Casino 400 at Auto Club Speedway is scheduled for 3:30 p.m. ET Sunday, but the area is expected to be impacted by hazardous wintry conditions in the days leading up to the race. Blizzard and winter storm warnings in the area north of Fontana, and flood warnings in Fontana have been made by the National Weather Service’s San Diego office.

NASCAR races are often impacted by rain; the precipitation reduces traction on the racing surface. Snow is not often an issue. One of the more recent instances was in March 2018 at Martinsville Speedway when the STP 500 was postponed until Monday because of snow in Virginia.

Here’s what you need to know about the weather in Fontana, Calif., this weekend.

MORE: Watch the Pala Casino 400 live with fuboTV (free trial)

Pala Casino 400 weather updates

Saturday, Feb. 25

Heavy rains in Fontana have cancelled both the practice and qualifying sessions for the Xfinity Series and the Cup Series races at the Auto Club Speedway. The lineups for both races was determined by NASCAR’s formula, that takes into account owner’s points position (35 percent), owner’s final race position (25 percent), driver’s final race position (25 percent) and fastest lap time position (15 percent).

After several hours of postponing the Xfinity Series race due to the rain on Saturday, the Production Alliance Group 300 was moved from its original start time on Saturday night to Sunday night after the Cup Series race. The Xfinity Series race will now start at approximately 8 p.m. ET on Sunday.

The National Weather Service continued to have flood watch in Fontana until 10 p.m. PT on Saturday (1 a.m. ET on Sunday) and a winter weather advisory in place on the area until 4 p.m. PT (7 p.m. ET). The forecast for Sunday calls for only a slight chance of rain (20 percent at night) and for it to be partly sunny during the day with a high of 48 degrees.

Friday, Feb. 24

The National Weather Service on Thursday issued a blizzard warning and a winter storm warning for the San Bernardino County mountain area, which is north of Fontana, adding it would be “very difficult to impossible” to travel in the conditions. The blizzard warning is in effect through 4 p.m. PT (7 p.m. ET) Saturday.

The San Diego forecasters noted that it was the first time in the history of the office that a blizzard warning had been issued for the county.

According to the forecast map, Fontana will be just to the south of the blizzard warning but still under flood and wind advisories on Saturday, per the weather service.

And there won’t be blizzard conditions just to Fontana’s north. Los Angeles County, which is west of Fontana, is also under a blizzard warning, with the weather service saying there could be up to 5 inches of snow and winds up to 55 mph.

The forecast for Sunday is for partly sunny skies and temperatures in the high 40s.

This post will be updated with weather reports closer to the start of the race.