SEATTLE – Heavy rains and winds from a Pacific storm lashed Western Washington on Monday, with the National Weather Service issuing “record severity” flood warnings for eight rivers. Gov. Chris Gregoire declared a state of emergency for 18 counties.

A hunter was reported missing in the swollen Cowlitz River in southwest Washington after a riverbank collapsed beneath his vehicle. Residents of low-lying areas near rivers and streams were encouraged to move to higher ground, as some rivers were expected to surpass flood stage by more than 10 feet, including the Snohomish River near Monroe and the Skykomish River near Gold Bar, northeast of Seattle.

The warm, moisture-heavy storm that came onshore during the weekend would continue over the region through Wednesday, the weather service said, with intense rainfall predicted through Tuesday in some areas.

A number of rivers jumped their banks Monday, including the Snohomish and Skykomish. The weather service said water was expected to cover farms, flood some rural homes and close many roads, and was not expected to recede in some areas until Friday.

In Snohomish County, where more than a dozen roads had been closed Monday, a sheriff’s office helicopter rescued several transients stranded on a Skykomish River sand bar near Sultan, where they had been camping. To the north in Sedro-Woolley, United General Hospital evacuated about 15 patients as a precautionary measure.

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 – Highway 410 over Chinook Pass.

“We want to prevent visitors getting trapped inside the park. The road is vulnerable to washouts in several key places, and there is only one way out,” said Superintendent Dave Uberagua.

Gregoire’s declaration allows state agencies in the 18 western and central Washington counties to spend money and use resources to aid local governments and communities. It also authorizes the Washington National Guard to activate, and the state Emergency Management Division to coordinate state assistance.

Although Seattle’s morning commute was snarled by drenching rains and overflowing drains, most of the flooding was in rural areas. A mudslide closed part of South Spokane Street, a main road in industrial South Seattle.

Record flooding was expected on the Snoqualmie River near Carnation, the Skykomish River near Gold Bar, the Snohomish River in the town of Snohomish, the North Fork of the Stillaguamish River at Arlington, the South Fork of the Stillaguamish near Granite Falls, the Carbon River near Fairfax, the Skagit River near Mt. Vernon, and the Cowlitz River in Packwood and Randle.

Less severe flood warnings were issued for other rivers, including the Naches, Cowlitz, Lewis, White, Elwa, Nooksack, Puyallup, Carbon, Boagachiel and Satsop rivers.

As of Monday afternoon, Stampede Pass on the Cascade crest east of Seattle had 4.42 inches of rain in the previous 24 hours, while Seattle-Tacoma International Airport recorded 2.66 inches, Bremerton had 3.29 inches and Olympia had 2.76.

High winds and a high tide Monday afternoon were expected to intensify flood conditions, the weather service said.

The forecast called for 6 to 10 inches of rain in the Cascades in the 24 hours ending Monday night. Weather service forecasters issued flood warnings for all Western Washington counties except for Skamania County north of the Columbia River, where a flood watch was in effect.

The Snoqualmie River was expected to surpass its 54-foot flood stage Monday and rise as high as 61.5 feet by late Tuesday morning. The Snohomish River was expected to rise to near 25.4 feet by late Tuesday morning – more than 10 feet above flood stage.

Evacuations were being encouraged in eastern Skagit County, with the Skagit River expected to reach record levels near Concrete, where floodwaters caused $17 million of property damage and 3,400 households were evacuated in 2003, said county spokesman Dan Berentson. He said the weather service warned county officials to expect worse conditions than the 2003 flood.

An emergency shelter was set up at the First Baptist Church in Hamilton, where Pastor Ron Edwards said people started to arrive around noon.

A less serious flood watch was issued for the less populated eastern slopes of the Cascade Range, and wind warnings were issued for gusts to 45 mph in much of Eastern Washington and to nearly 60 mph west of the Cascades. Gale force winds were forecast for most of the state’s marine waters, including Puget Sound.

The Lewis County sheriff’s office said a 20-year-old Seattle elk hunter was missing after his pickup truck was swept into the rising waters of the Cowlitz River south of Mount Rainier early Monday. The man was in his truck east of Packwood when the river bank collapsed, Sheriff Steve Mansfield said.

The truck was Later spotted in the river, but authorities were unable to determine whether the driver was still in it, Mansfield said.

Searchers from the Packwood and Randle fire departments had successfully evacuated 200 to 225 elk hunters in 60 to 70 hunting camps near the Cowlitz River Monday morning, Mansfield said.

Urban flood warnings were issued for clogged storm drains and overflowing streams in Western Washington, and coastal flooding from heavy surf and high tides. High water over a road blocked the north entrance to the parking garage at Seattle-Tacoma International Airport Monday morning, said airport spokesman Bob Parker.