Following a record dry February, a storm will send rain and mountain snow to California and the balance of the Southwestern states into Monday.San Francisco will end the month with no measurable rainfall (0.01 of an inch or greater), which has not happened in February since the 1860s.Redding, Sacramento and Ukiah, California, will also end this month with no measurable rainfall in February for the first time in recorded history. These cities average 5.71, 3.59 and 7.24 inches, respectively, during the month.The unprecedented lack of moisture has led to a rapid expansion of abnormally dry to moderate drought conditions. Such conditions are affecting close to 6 million California residents, which is up from around 1.35 million residents just last week, according to the United States Drought Monitor.Forecasters say that not enough rain will fall with the latest storm to ease the growing drought concerns. "Precipitation from this system will be light, with amounts mostly less than 0.10 of an inch," AccuWeather Senior Meteorologist Heather Zehr said."A few places, mainly in upslope areas, may do better," she added.The spotty showers could lead to minor disruptions on the roadways, including around Los Angeles and San Diego, from Sunday into Sunday night.Cold air aloft could support the eruption of spotty thunderstorms, particularly along the California coastline, according to Zehr.Small hail is possible in any robust thunderstorms that may develop across Southern California.Wet weather that moves through the Los Angeles region could impact the NASCAR race Sunday afternoon."With the race starting just after 12:30pm local time in Fontana, CA, we will be approaching the best time for any showers to form," said AccuWeather Senior Meteorologist Alan Reppert."With the storm dipping southward over the area, we could see even a thunderstorm around which would cause a delay and could even evacuate the stands," Reppert added."Snow levels are expected to drop to 3,500 to 4,000 feet," Zehr said."This could allow for snow showers to occur over Tejon Pass and Cajon Pass, and perhaps bring a few inches of snow to elevations above 5,000 feet," she added.Travelers are urged to use caution on the roadways as slippery conditions could quickly develop as temperatures plunge on Sunday night.Travel will be difficult across Interstate 80's Donner Pass this weekend with over half a foot of snow expected to pile up.Snowfall will not just be confined to California, with several inches of accumulation likely to require shovels and plows from northern and central Nevada to Utah, Wyoming and Colorado from Sunday into Sunday night.Roadways can turn slippery around Salt Lake City and Denver with 1-3 inches of snow predicted. By Monday, rain, snow showers and localized thunderstorms will shift into the Desert Southwest as drier, milder weather returns to central and Southern California.This storm will later fuel flooding downpours and potentially severe thunderstorms across the central and southern United States around the middle of the week.Keep checking back on AccuWeather.com and stay tuned to the AccuWeather Network on DirecTV, Frontier and Verizon Fios.