Washington Joins Oregon, California and more as Pineapple Express Brings Historic Flooding, Mudslides, and Travel Disruptions to the Pacific Northwest

Published on December 15, 2025

The Pacific Northwest is bracing for historic flooding and significant travel disruptions as the region faces yet another round of intense weather caused by the infamous Pineapple Express. A powerful atmospheric river, known for its heavy rainfall and snow, is set to impact Washington, Oregon, and Northern California from Monday, December 15, 2025, through mid-week. This latest storm event, expected to bring an additional 2–4 inches of rain, could trigger widespread flooding, mudslides, and damaging winds, with major implications for travelers and locals alike.

The Pineapple Express: What You Need to Know

The Pineapple Express refers to a type of atmospheric river — a narrow band of concentrated moisture that originates near the Hawaiian Islands. When this moisture-rich air flows towards the Pacific Northwest, it brings unrelenting rain, higher-than-normal temperatures, and sometimes snow at higher elevations. The term Pineapple Express is derived from the tropical region it originates from, and it’s known to produce heavy rainfall that can result in significant flooding, mudslides, and other weather-related hazards.

This week’s storm is expected to be particularly severe, as the atmospheric river will bring record-breaking rainfall, mountain snow, and strong winds across Western Washington, Oregon, and Northern California. Residents of the Pacific Northwest are already on high alert, and the National Weather Service (NWS) has issued flood warnings and wind advisories for the affected regions.

The storm is set to unleash persistent rain on areas that have already received substantial rainfall in the past week. Washington State, Oregon, and parts of California will bear the brunt of the storm. As a result, numerous rivers are expected to crest well above their flood stages, with some locations seeing floodwaters higher than ever before.

Government Warnings and Travel Alerts

Both state and federal government authorities have issued emergency declarations for Washington and Oregon due to the severity of the expected storms. On December 10, 2025, the Governor of Washington, Bob Ferguson, declared a state of emergency in response to the widespread flooding, mudslides, and damaged infrastructure that were already affecting parts of the state. This emergency declaration allows the state to request federal assistance and deploy emergency resources to areas most impacted by the storms.

The Federal Emergency Management Agency (FEMA) has activated disaster response teams to assist in evacuation efforts, while local agencies are on standby to help with flood mitigation and recovery efforts. Travelers planning to visit Washington, Oregon, or California this week are urged to stay updated on local travel advisories and weather warnings from official sources such as the National Weather Service and state departments of transportation.

Impact on Travel: What You Should Expect

Travelers planning to visit or transit through the Pacific Northwest this week should be prepared for widespread delays and disruptions across all forms of transportation. Airports in Seattle-Tacoma (SEA), Portland International (PDX), and San Francisco International (SFO) are expected to experience flight delays and cancellations due to low visibility, heavy rain, and strong winds. Flight schedules could be further disrupted as airports work to clear runways from floodwater and debris.

The NWS has warned that high winds of up to 50 mph will occur along the coast, with gusts reaching 90 mph in the northern Rockies. This could lead to crosswind hazards for drivers on highways like Interstate 5 and Interstate 90, especially for high-profile vehicles such as trucks and buses. Travelers should expect road closures due to rising floodwaters and landslides, especially on routes through Washington’s Cascades and Oregon’s Coastal Range. According to the Washington State Department of Transportation (WSDOT), certain mountain passes like Stevens Pass and Snoqualmie Pass could see snow levels drop as low as 4,000 feet, causing travel disruptions for those planning to drive through the Cascades.

Beyond the airports and highways, rail services may also face disruptions. Amtrak passengers traveling on the Coast Starlight or other routes through the Pacific Northwest could see delays due to flooding and washed-out tracks. As floodwaters rise, rail operators may be forced to temporarily halt services for safety reasons.

Outdoor and Adventure Travel: Stay Cautious

The Pacific Northwest is renowned for its outdoor and adventure tourism, particularly in the mountain regions and national parks. However, this storm will make hiking and outdoor exploration potentially dangerous due to mudslides, flooded trails, and rapidly rising rivers. Visitors to Mount Rainier National Park, Olympic National Park, or other popular destinations should reconsider outdoor plans this week and adhere to local advisories regarding trail closures or restricted access.

What Can Travelers Do to Stay Safe?

• Stay updated: Travelers should check official weather warnings from the National Weather Service and state transportation departments regularly to stay informed about flood risks, road closures, and weather conditions.
• Book flexible tickets: If you’re flying into or out of Seattle, Portland, or other airports in the region, consider booking flexible flights in case of delays or cancellations.
• Avoid non-essential travel: If you’re in Washington, Oregon, or California, try to avoid traveling in flood-prone areas, especially in low-lying regions that are prone to flash floods.

Conclusion: The Storm’s Aftermath and Long-Term Impact

The Pineapple Express storm’s arrival marks a significant challenge for travelers and residents alike in the Pacific Northwest. With flooding, mudslides, wind damage, and travel disruptions, the region will be dealing with the storm’s aftermath for days to come. Whether you’re planning a visit to Seattle, Portland, or any other city in the area, it’s important to keep abreast of the latest weather reports and transportation updates to ensure a safe and seamless journey.

While these storms may cause temporary disruptions, the Pacific Northwest remains a stunning and adventurous destination for nature lovers, and this latest weather event underscores the region’s importance as an outdoor escape — albeit a challenging one in the winter months. Always ensure your safety comes first before venturing into these wild and unpredictable conditions.