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Heavy Rainfall to Bring Flooding Threat to California; Heavy Snow in the Sierra

A strong atmospheric river will bring heavy rainfall to California through the holiday week. The heaviest rainfall is expected on Wednesday in the Los Angeles Basin. Flash and urban flooding is possible. A prolonged heavy snowfall is expected in the Sierra Nevada from the atmospheric river, raising concerns for major snow‐load impacts. Travel may be difficult to impossible over the passes. Read More >

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Welcome to the National Weather Service’s Hazards Simplification Initiative!

The Hazard Simplification (Haz Simp) initiative is leveraging user engagement research to explore and implement advancements in our national Watch, Warning, and Advisory alerting system. This iterative and flexible approach allows the National Weather Service (NWS) to continually engage with its partners and stakeholders to ensure the alert products we issue reflect current and future needs.

From consolidating the number of individual alerts to creating new visuals to utilizing plain language, the NWS is always looking for new and more effective ways to communicate weather impacts to partners and the public!