SEATTLE (AP) – A windy Pacific storm dumped heavy rain Monday on western Washington, raising the threat of record-breaking flooding and closing the main road in Mount Rainier National Park.

Gov. Chris Gregoire declared a state of emergency for 18 counties, authorizing the National Guard to activate and the state Emergency Management Division to coordinate assistance.

Officials at Mount Rainier National Park, which had 7 inches of rain Sunday and was expecting 10 more Monday, closed the main park road, turned visitors away and sent employees home early via the only exit road open.

The National Weather Service warned county officials to expect worse conditions than in 2003, when flooding caused $17 million in property damage in Concrete and 3,400 households were evacuated, he said. Residents began showing up at one shelter by midday, and a hospital evacuated 15 patients as a precaution.

The warm-weather rainstorms, propelled by air currents from Hawaii in a pattern called the Pineapple Express, could cause flooding of record proportions, the weather service said. Several rivers had already jumped their banks.

The Army Corps of Engineers was sandbagging several rivers. At least 200 hunters were evacuated from about 65 hunting camps near the Cowlitz River.

As of early Monday afternoon, Stampede Pass on the Cascade crest east of Seattle had 4½ inches of rain in the previous 24 hours, while Seattle-Tacoma International Airport recorded more than 21/2 inches. The forecast called for 6 to 10 inches in the Cascades and about 3 inches in the Seattle area in the 24 hours ending Monday night, with most rivers expected to crest Tuesday.