Rain Chances for the Christmas Storm in Southern California

Southern California Prepares for a Wet Christmas

Los Angeles—Southern California is bracing for a significant weather event as the National Weather Service (NWS) predicts a powerful atmospheric river will impact the region from December 23 to December 26. This weather system is expected to bring heavy rainfall and substantial mountain snow just as holiday travel peaks.

The NWS anticipates rain totals of 2 to 4 inches across coastal and valley areas, while foothills and mountainous regions could see double that amount. The forecast also indicates that northern California and the Sierra Nevada could experience heavy precipitation starting as early as December 21.

Timeline of Rainfall

Los Angeles County

• Dec. 23: 10-20% chance of rain
• Dec. 23 night: 30-50%
• Dec. 24: 80-100%
• Dec. 24 night: 80-100%
• Dec. 25: 60-70%
• Dec. 25 night: 30-50%
• Dec. 26: 30-50%
• Dec. 26 night: 10-20%

Ventura County

• Dec. 23: 10-20%
• Dec. 23 night: 30-50%
• Dec. 24: 80-100%
• Dec. 24 night: 80-100%
• Dec. 25: 60-70%
• Dec. 25 night: 30-50%
• Dec. 26: 30-50%
• Dec. 26 night: 10-20%

Santa Barbara County

• Dec. 23: 30-50%
• Dec. 23 night: 60-70%
• Dec. 24: 80-100%
• Dec. 24 night: 80-100%
• Dec. 25: 60-70%
• Dec. 25 night: 30-50%
• Dec. 26: 30-50%
• Dec. 26 night: 10-20%

Other Counties

• Orange County: Ranging from 47% on Dec. 23 to 54% on Dec. 26.
• Riverside County: Starting at 30% on Dec. 23, peaking at 70% on Dec. 24.
• San Bernardino County: Beginning at 30% on Dec. 23 with a high of 69% on Dec. 24.

Safety Concerns

Forecasters have voiced concerns over safety as the storm’s timing coincides with the height of holiday travel. The NWS urged the public to stay informed about the evolving forecast. In a recent social media update, they mentioned, "Exact timing uncertain. Amounts and impacts also uncertain… Start to mentally prepare for a wet Christmas holiday."

Several specific dangers associated with this weather system include:

• Road Conditions: Heavy rain following a prolonged dry spell can create slick roads. Major mountain passes, including the Grapevine, may face closures or strict chain requirements due to snow.
• Flooding and Debris: Elevated risks of flash flooding and landslides are expected, especially in areas affected by recent wildfires where soil absorption is compromised.
• Utility Disruptions: Rain-soaked grounds coupled with gusty winds increase the likelihood of downed trees and potential power outages.

Recommendations

Officials advise residents to monitor weather updates as the holiday approaches. For those traveling through mountain passes, carrying snow chains, maintaining a full gas tank, and having a winter emergency kit are strongly recommended. Additionally, residents should clear rain gutters and secure outdoor decorations before winds intensify mid-week.