Caltrans encourages motorists to keep a winter emergency kit in their vehicles with supplies such as blankets, flashlights, water, jumper cables and basic tools to prepare for unexpected breakdowns and hazardous road conditions. Photo by Caltrans

MARYSVILLE, CA (MPG) - With winter weather approaching, Caltrans is urging Northern California motorists to prepare their vehicles and review driving precautions before rain, snow and icy conditions affect regional highways.

The reminder comes as an early-season storm begins affecting the Sacramento Valley, foothills and Sierra Nevada, bringing attention to changing road conditions and the importance of preparing for winter travel.

According to the National Oceanic and Atmospheric Administration's winter outlook, El Niño will likely influence weather patterns from December 2026 through February 2027. The outlook calls for above-average temperatures across the northern United States and wetter-than-average conditions across the southern states.

However, forecasters cannot yet determine how many storms will affect the Sacramento Valley and Sierra Nevada, their intensity or how much precipitation they will produce.

Caltrans recommends that drivers inspect their vehicles before winter weather arrives. Motorists should check coolant levels, replace worn windshield wipers and inspect tire pressure and tread depth.

Drivers traveling into the mountains should also carry tire chains or approved traction devices. Snow tires must have a tread depth of at least 6/32 of an inch.

Caltrans also recommends carrying emergency supplies, including flashlights, extra batteries, blankets, warm clothing, food, water, gloves, an ice scraper and a shovel. Sand or kitty litter can provide additional traction if a vehicle becomes stuck.

Motorists should allow extra travel time, reduce speeds and maintain a full fuel tank or sufficient electric vehicle charge when traveling into the Sierra Nevada.

Caltrans advises drivers to turn off cruise control during hazardous weather and remain alert for black ice. Four-wheel-drive and all-wheel-drive vehicles may provide better traction when climbing hills, but they do not improve stopping ability.

Fog and flooding also create hazards throughout the Sacramento Valley. During foggy conditions, motorists should reduce speeds, use low-beam headlights and follow the white line along the right edge of the roadway.

Drivers should never attempt to cross flooded roads and should seek alternate routes when encountering standing or moving water.

California's Move Over law also requires drivers to slow down and, when safe, change lanes when approaching Caltrans or emergency vehicles displaying flashing warning lights.

Before traveling, motorists can check weather forecasts through the National Weather Service and road conditions, closures and chain requirements through Caltrans QuickMap.

Road information is available at quickmap.dot.ca.gov or by calling 1-800-427-7623.