White Christmas ahead for parts of western US (with forecast video)

Tractor-trailer on I-70 in Colorado, surrounded by snow-covered mountains and grass.

If you’re dreaming of a white Christmas this year, you will have to go out West. A winter storm will spin over the Great Bains and the Rocky Mountains for a few days, dumping plenty of fresh snow in the mountains. In some areas, gusty winds will produce blowing snow and occasional whiteout conditions. Truckers will have chain up as they make last-minute deliveries or try to get home for the holiday.

SONAR Critical Events and radar: Monday, Dec. 23, 2019, 11 a.m. EST

Today and this evening, Dec. 23, heavy snowfall will cover several areas of California. Let’s start with the mountains of Ventura and Los Angeles counties in Southern California. For areas above 7,000 feet, such as Mount Pinos, this means up to 12 inches of accumulation; for areas between 5,000 and 7,000 feet, like Mount Wilson, this means 6 to 12 inches; and for lower slopes like Lockwood Valley, Acton and Sandberg, this means much lighter amounts. A few inches may even hit below 2,000 feet along the I-5 corridor, including Grapevine.

Up to 6 inches will pile up in parts of the San Bernardino mountains, including Lake Arrowhead, Big Bear City, Big Bear Lake, Running Springs and Wrightwood. Amounts in nearby peaks above 7,000 feet could exceed 12 inches. Meanwhile, portions of the southern Sierra Nevada range could see several more inches of snowfall today, mostly above 5,000 feet. This would be in places like Devils Postpile, Florence Lake, Lake Thomas Edison, Tuolumne, Meadows, Fish Camp, Wawona, Shaver Lake, Camp Nelson, Giant Forest, Lodgepole, Grant Grove and Johnsondale.

Up to 8 inches of new snow could accumulate in the White Mountains and the Sierra Nevada of eastern California. Higher amounts are possible along the Sierra crest. This will make driving difficult at times on sections of CA-168, including Westgard Pass and between Bishop and Aspendell.

Snowfall will gradually get heavier later today in Nevada across the Sheep Range, Spring Mountains and Red Rock Canyon (just west of Las Vegas) this afternoon, possibly lasting on and off through Christmas. Snow showers in these areas may continue through Christmas.

The storm will also produce periods of snowfall through Christmas, and possibly beyond Christmas, across Utah, Arizona and the Rocky Mountains. Some high elevations in southern Utah could see totals up to 14 inches, with several inches for the mountains of northern and eastern Arizona, including Grand Canyon and Flagstaff. Anywhere from 8 to 15 inches of snowfall are possible in the high elevations from southern Colorado into northern New Mexico, north of I-40.

Other notable weather today, Dec. 23

Periods of heavy rainfall continue today across southern California, from Los Angeles and San Diego eastward to inland communities. Totals of 1 to 2 inches could cause street flooding in urban areas with insufficient/clogged drainage systems.

SONAR Critical Events and radar: Monday, Dec. 23, 2019, 11 a.m. EST

Soaking rains in the Southeast will increase the risk of flooding and vehicles hydroplaning. The I-95 corridor from Savannah, Georgia, to the South Carolina-North Carolina border and eastward to the coast are the target areas. Drivers could run into delays due to reduced visibility or road closures. The National Weather Service (NWS) has issued a flood watch and a flash flood watch across the region.

Additional notes

Although widespread, heavy rain that fell from last Thursday through Saturday, Dec. 19 to 21, has faded across western Washington state, the threat of landslides remains. Potential slides may cut off access to sections of I-5 or other routes.

Have a great day and a wonderful Christmas and please be careful out there!