A major atmospheric river (AR) is forecasted to make landfall over northern and central California from Tuesday, April 1, to Wednesday, April 2, 2025, with a high likelihood exceeding 80%, according to the National Centers for Environmental Prediction (NCEP) model guidance.
The Global Ensemble Forecast System (GEFS) has consistently indicated a strong signal for this landfalling AR since last Friday.
The National Weather Service (NWS) Climate Prediction Center’s recent outlooks also suggest a greater than 60% probability of wetter-than-normal conditions between March 31 and April 4, with a moderate risk of heavy precipitation and mountain snow on April 2, extending from southern Oregon to central California.
Although confidence is high, the event is still 5 to 6 days out, and while the Global Forecast System (GFS) consistently signals a strong atmospheric river, the European Centre for Medium-Range Weather Forecasts (ECMWF) presents a somewhat less impactful scenario, leading to some uncertainty…