"Bomb Cyclone" to Bring Intense Rain, Snow, and Flooding to West Coast

Rainfall totals could reach 8 to 12 inches, with localized areas seeing up to 15 inches, north of San Francisco into Oregon.

A potent bomb cyclone developing over the northern Pacific is set to unleash a powerful atmospheric river across the West Coast this week, delivering heavy rain, snow, and strong winds from Northern California to Washington. The National Weather Service warns of widespread impacts, including flooding, mudslides, and hazardous travel conditions. The storm, expected to peak between Tuesday and Friday, will undergo bombogenesis, a rapid pressure drop of at least 24 millibars in 24 hours, signaling a rapidly intensifying system. It will channel moisture-packed atmospheric river conditions into the region, with Northern California and southwest Oregon bearing the brunt.

Rainfall totals could reach 8 to 12 inches, with localized areas seeing up to 15 inches, north of San Francisco into Oregon. Coastal areas and foothills across Oregon and Washington may experience 1 to 5 inches of rain. Poor drainage areas, creeks, and rivers are at high risk of flooding. Recent wildfire burn areas face additional threats of mudslides and rockslides along mountain routes. Mountain regions will see heavy snowfall, creating travel challenges and boosting avalanche risks. Winds may reach dangerous speeds, particularly in exposed areas, increasing the potential for downed trees and power outages.

Residents are urged to monitor forecasts and prepare for rapidly changing conditions. Updates are available on platforms like Weather.com and the National Weather Service to stay informed about this significant weather event.