Whiteout conditions possible in W. Washington mountains this weekend

A cool, wet front is moving over Western Washington starting Friday, making excursions into the highlands potentially treacherous for hikers and skiers.

The weather pattern is likely to bring showers beginning in the early afternoon, according to the National Weather Service in Seattle. Behind that is “a pool of moist and unstable air” that could bring thunderstorms on Saturday and Sunday afternoons and evenings, as well as the possibility of snow and whiteout conditions at higher elevations, said meteorologist Doug McDonnal.

“We’re transitioning to showery and rather cool weather with a high right around 60,” he said. The normal high in Seattle this time of year is around 69 degrees, McDonnal said.

In the mountains, the snow level could dip to as low as 4,000 feet and a few inches of snow are likely above that elevation, he said.

“This is the time of year people go out hiking or do some mountaineering at Mount Baker and Mount Rainier,” McDonnal said. “It’s also popular to go skiing starting at Paradise and going up to Camp Muir. But this is the kind of weather where there could be whiteout conditions, which make navigation very tricky, and it’s easy to end up getting wet and cold.”

The four Seattle Boy Scouts who were rescued earlier this week on Mount Baker became lost due to whiteout conditions, McDonnal said.

Travelers to the mountains or any alpine terrain this weekend should at minimum have a GPS system and know how to use it, he said.