Model severe atmospheric river storm sequences, calculate property inundation and debris flow risks, and generate an actionable emergency mitigation plan before winter storms hit.
Clear drains, test sump pump battery, inspect perimeter slopes, clear rooftop channels, and secure patio furniture.
Deploy sandbags at low thresholds. Stage vehicle facing out with full fuel tank. Charge phone banks and radios.
Shelter in interior upper rooms if lower levels flood. Never drive across water-covered roads. Monitor county alerts.
Inspect foundations for erosion or cracking. Document water intrusion before cleanup. Check tap water boil notices.
El Niño events arise from prolonged, anomalously warm equatorial Pacific sea surface temperatures (>2.0°C anomaly). In winter, this shifts the Pacific jet stream southward, funneling intense atmospheric river (AR) plumes directly into California and the West Coast, causing high-volume continuous precipitation events.
The Ralph et al. AR scale rates storm plumes from Category 1 (primarily beneficial) to Category 5 (predominantly hazardous). Super El Niño seasons often trigger back-to-back Category 4 and 5 systems that leave zero drying time between rainfall surges, inducing saturated soil failures.
Turn around, don't drown: 6 inches of moving water can knock down an adult, and 12 inches can sweep away small cars. Sign up for county Nixle and Everbridge emergency alerts, keep NOAA weather radio operational, and prepare evacuation paths away from canyon mouths.