Multiple atmospheric rivers brought widespread flooding to Snohomish County, Washington, this week, forcing water rescues and road closures as the Snohomish River approached its fourth-highest crest on record
Residents along the Skagit River in Washington have been ordered to evacuate as the river is forecast to reach 13.55 m (44.47 feet) by late December 11, 2025. Heavy rainfall and rising rivers have led to emergency declarations across Washington State.
A major atmospheric river is producing very heavy precipitation across western Washington today into early December 11, 2025, triggering widespread and potentially historic riverine flooding, according to the Center for Western Weather and Water Extremes (CW3E). Forecasts indicate 130–200 mm (5–8 inches) of rain over the central and northern Washington Cascades and 75–130 mm (3–5 inches) over the Olympic Peninsula through 04:00 PST (12:00 UTC) on December 12. CW3E modeling shows 15 river gauges expected to exceed major flood stage and four to surpass record levels within 48 hours.
A strong atmospheric river brought significant flooding to parts of the Pacific Northwest through December 9, 2025, with rainfall rates in the Cascades exceeding 13 mm (0.5 inch) per hour and the Snoqualmie River cresting at 5.4 m (17.8 feet), its highest level in more than 10 years.
A tornado struck the rural community of Alfredo Chaves in Flores da Cunha on Monday, December 8, 2025, causing structural damage to dozens of residences and leaving hundreds without power.
Blizzard warning have been issued with snowfall totals of up to 30 cm (12 inches) being forecast across the high western slopes along with gusts of 80 km/h (50 mph) across multiple mountain counties. The warnings are in effect for parts of West Virginia, western Maryland, and western Virginia from 10:00 EST Wednesday, December 10, 2025 to 10:00 EST Thursday, December 11.
Two successive atmospheric river pulses are affecting the Pacific Northwest this week, delivering multi-day heavy rainfall and flooding risk across western Washington and northwestern Oregon. The first made landfall early December 9, and a stronger second pulse is forecast to arrive late December 9–early December 10, maintaining high integrated vapor transport and major flood potential through December 11.
An intense extratropical cyclone is forming on Tuesday, December 9, 2025, over Rio Grande do Sul, bringing widespread rainfall, severe thunderstorms, and damaging winds across southern Brazil.
Large portions of the northern United States are under winter storm warnings as a strong Alberta clipper advances into the Upper Midwest and separate winter storms persist across the northern Rockies from Tuesday morning through early Wednesday, December 9-10, 2025.
A rapidly deepening Atlantic low, named Storm Bram, is forecast to pass close to the western coasts of Ireland, Northern Ireland and the Outer Hebrides on Tuesday, December 9, 2025, bringing very strong southerly winds, heavy rain and exceptionally high seas. The system forms part of an active North Atlantic storm train linked to recent Polar Vortex disruption.
