Seattle Faces Prolonged Heavy Rainfall and Flooding Risks Amid Climate Concerns

Seattle is currently experiencing an extended period of heavy rainfall, which began on Thursday, December 4, 2025, and is forecasted to continue through Wednesday, December 10. The National Weather Service has issued warnings about multiple rainstorms, including several atmospheric rivers, expected to impact the region during this time. Seattle could receive up to 4 inches of rain, while the nearby Cascade and Olympic Mountains may see as much as 10 inches. The combination of gusty winds, high tides, and rapidly rising rivers raises concerns about coastal flooding, river flooding, and landslides. Residents are advised to prepare by using rain gear and clearing gutters.

Atmospheric rivers are narrow corridors of concentrated moisture in the atmosphere that can deliver significant amounts of rainfall over short periods. They are a common meteorological phenomenon in the Pacific Northwest and can account for up to 50% of the region's annual precipitation.

Seattle has a history of significant rainfall events leading to flooding and landslides. Notable instances include the December 2007 storms, where the Skokomish River set an all-time record-high flood level on December 3, 2007, with a maximum discharge of 29,000 cubic feet per second, leading to substantial flooding and infrastructure damage. Another significant event was the Hanukkah Eve Windstorm of 2006, which produced hurricane-force gusts and heavy rainfall between December 13 and 15, causing extensive damage and leaving over 1.8 million residences and businesses without power.

Recent studies indicate that rainfall in Seattle has become more intense due to climate change. Between 1970 and 2024, the city experienced a 6% increase in hourly rainfall intensity. This trend is attributed to human-driven climate change, which warms the atmosphere, allowing it to hold more moisture and produce heavier downpours.

The current heavy rainfall poses several risks to the Seattle area, including flooding, landslides, transportation disruptions, and economic impact. The combination of high tides and rapidly rising rivers increases the likelihood of both coastal and river flooding, potentially affecting homes, businesses, and infrastructure. Saturated soils from prolonged rainfall elevate the risk of landslides, particularly in areas with steep terrain. Flooded roads and potential landslides can lead to significant transportation challenges, affecting daily commutes and emergency response times. Damage to property and infrastructure can result in substantial economic costs for repairs and recovery efforts.

Residents are advised to take the following precautions:

• Clear Gutters and Drains: Ensuring that gutters and storm drains are free of debris can help mitigate localized flooding.

• Stay Informed: Regularly monitor updates from the National Weather Service and local authorities for the latest information and advisories.

• Emergency Kits: Prepare emergency kits with essential supplies in case of power outages or evacuation orders.

By taking these proactive measures, residents can help mitigate the risks associated with the forecasted heavy rainfall and contribute to the community's resilience in the face of extreme weather events.