A major weather event is set to strike the West Coast. A slow-moving low-pressure system brings long-duration atmospheric river conditions. This weather will impact the Pacific Northwest and California. Precipitation is expected from February 21 to February 25, 2026. This news is critical for residents across the affected regions.
Two Waves of Moisture Arrive
The atmospheric river will deliver moisture in two distinct pulses. The first pulse arrives Saturday into Sunday. It features southerly moisture flow. The second pulse is stronger. It moves north toward Oregon and Washington. This second wave will arrive early next week. The Center for Western Weather and Water Extremes (CW3E) noted high confidence in these conditions. Their forecasts show over 90% certainty for atmospheric river conditions. This is along the Oregon and California coasts.
Heavy Rains Target Northwest and Northern California
Southern Oregon and northern California will see the strongest impacts. The Coast Ranges and Klamath Mountains are most vulnerable. Forecasters predict 5 to 10 inches of rain there. This amount is significant. Marginal excessive-rainfall outlooks are in place. These cover western Oregon and northern California. The outlooks expand south into central California. They also include the Sierra Nevada. The Weather Prediction Center expects 125–250 mm of rain. This is over a 72-hour period ending February 25.
Sierra Nevada Faces Snow and Rain
Precipitation levels in the Sierra Nevada will be high. However, freezing levels remain high. Most precipitation will fall as rain, not snow. This increases runoff potential. River and stream levels are likely to rise. This is expected across western Oregon. It also affects northern and central California. Rain falling on existing snowpack may accelerate melting. This can further increase runoff. The National Weather Service (NWS) issues these warnings.
Snow Blankets Mountain Ranges
Meanwhile, the Sierra Nevada will receive heavy snow. Some mountain zones could see up to 8 feet of snow. Snowfall rates may exceed 3 inches per hour. This presents extreme travel hazards. Conditions above pass level are dangerous. They could become impossible to navigate. Avalanche risks will also increase significantly. Several ski resorts have already reported massive snow totals. This marks a welcome change after a dry spell.
Flood and Wind Threats Loom
Heavy rainfall increases flood risks. Excessive rainfall outlooks highlight this danger. Flash flooding is a concern. Debris flows are possible in burn scar areas. These are regions impacted by recent wildfires. Coastal areas may also see flooding. Up to 1.5 feet of inundation is possible. This affects some San Francisco Bay shore areas. Monterey Bay could also experience flooding. Strong winds will accompany the storms. Gusts between 50 and 70 mph are possible. Small craft advisories are in effect for coastal waters. Mariners should stay informed about conditions.
Beneficial Rain Amidst Risks
This storm system follows a drier-than-normal period for parts of California. The precipitation will be beneficial. It aids water supply efforts. It improves ski conditions. However, it also raises flood and avalanche risks. CW3E and NOAA are closely monitoring the system. Their data guides public safety alerts. Residents in affected areas should heed all warnings. Preparedness is key during such events. This is important news for the entire West Coast.
