A strong atmospheric river (AR) is set to impact the Southeastern and Northeastern U.S. this week, bringing anomalously high moisture levels and the potential for heavy rainfall and rapid snowmelt. Forecasts indicate the system will strengthen between December 10 and 11, driven by a plume of tropical moisture from the Gulf of Mexico and a cold front.
An atmospheric river is forecast to bring significant precipitation to Washington and Oregon between Friday and Saturday, December 6 and 7, 2024, with the Olympic Peninsula and North Cascades expecting up to 127 mm (5 inches) of rainfall and AR2 conditions likely in southern Washington and northern Oregon. While confidence is high regarding the occurrence of the event, uncertainties remain in its duration, intensity, and precise timing due to variability among GEFS ensemble model predictions.
A new atmospheric river is forecast to bring heavy rain and significant snowfall to California starting Monday, November 25, 2024, with potential flash flooding and major winter storm impacts in central and southern regions, according to the Center For Western Weather and Water Extremes (CW3E).
Two powerful Pacific storm systems and an atmospheric river event will continue impacting the Pacific Northwest and northern California through the end of this week with heavy rain, flooding, strong winds, and higher-elevation mountain snow.
A powerful AR4 atmospheric river made landfall in the Pacific Northwest and Northern California on November 19, 2024, bringing prolonged rainfall, heavy snowfall, and significant flooding risks that are expected to worsen through November 22. Meteorologists warn that the storm could bring up to 380 mm (15 inches) of rain to the Coast Ranges and Sierra Nevada, with some areas potentially receiving more.
The National Weather Service (NWS) in Medford, Oregon, is warning residents that the incoming atmospheric river could stall across the region, leading to a prolonged period of moderate to heavy rainfall. The highest amounts are expected in Curry County, with a potential threat that the Coquille River at Coquille could reach a minor flood stage.
The latest model guidance suggests a major atmospheric river could hit the Pacific Northwest and Northern California early next week, with the ECMWF EPS control member forecasting AR3-4 conditions from central Oregon to Northern California. Although timing and duration remain uncertain, 70% of EPS members predict AR4 or AR5 conditions in coastal southern Oregon, according to the Center for Western Weather and Water Extremes (CW3E).
A strong Atmospheric River is set to bring significant low-elevation rain and high-elevation snow to the Pacific Northwest and Northern California beginning Tuesday evening, November 12, 2024. The system will continue moving eastward, impacting a wide swath of the western and central United States with varied precipitation, including rain, snow, and thunderstorms.
Two atmospheric rivers are set to bring heavy rainfall and flood risks to the Pacific Northwest and Northern California from November 10 to November 14. The storms are expected to bring significant precipitation, with the heaviest rainfall forecast for the Olympic Peninsula and Cascade Mountains. The peak rainfall is predicted to occur between November 10 and November 13.
An atmospheric river event continues directing subtropical moisture over much of California on Monday, February 19, 2024. Heavy coastal and low elevation rain, thunderstorms, heavy mountain snow and high winds are all expected from this new atmospheric river event.
