Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 320 PM EST Wed Dec 24 2025 Valid 00Z Thu Dec 25 2025 - 00Z Sat Dec 27 2025 ...Life-threatening flash flooding continues over Southern California today and tomorrow; heavy mountain snow and high winds also ongoing... ...Impactful wintry weather to spread from the Upper Midwest into the Mid-Atlantic/Northeast Friday... ...Unseasonable, record breaking warm weather continues across the Nation's mid-section through Christmas into this weekend... This afternoon, an analysis of our weather pattern across the Lower 48 highlights an anomalous mid-level high pressure ridge anchored over the Nation's Heartland, which is flanked by an equally amplified trough over the Eastern Pacific. Unfortunately, this configuration will maintain life-threatening atmospheric river conditions focused over Southern California through Christmas day, where widespread flash flooding is underway amid persistent 0.5" to 1"/hour rainfall rates. Accordingly, a rare High Risk of Excessive Rainfall remains in effect through tomorrow morning over Southern California, which includes the Los Angeles metropolitan area. Flash/urban flooding aside, the barrage of heavy rainfall will also lead to dangerous rock/mud slides across Southern California through Christmas day. Users in the affected area are encouraged to have multiple ways of receiving warning information, NEVER drive through flooded roads, and be aware that the threshold for