There’s nothing but rain in the forecast for the next week in Western Washington, prompting meteorologists to warn that lowland flooding and landslides are possible.
“It looks to be pretty wet, with heavy rain in the mountains instead of snow. That’s going to run right into the rivers,” said Johnny Burg, with the National Weather Service in Seattle.
As much as a quarter-inch to a half-inch of rain is possible daily through the weekend, Burg said.
Snow will continue this week in the North Cascades until Sunday, when temperatures are expected to rise above freezing.
Heaviest rain is forecast Sunday night and Monday, during a warming trend that will drop the snow level to about 5,000 feet – approximately the level of Panorama Dome at Mt. Baker Ski Area.
Lowland high temperatures will be in the mid-40s, with mountain highs in the 20s until Sunday.
In addition, heavy snowfall in the mountains this week has added to extreme avalanche danger in the North Cascades, according to the Northwest Avalanche Center.
“It could snow more for the next several days, then it will start to warm,” Burg said.
A similar cycle of warm, rainy weather occurred in December and the Whatcom County lowlands saw minor flooding along the Nooksack River.
“We’re just seeing system after system, one right after the other,” Burg said. “That’s kind of what winter is around here.”
Since the first week of January, 12 of the past 20 days have seen a high temperature of 48 degrees or warmer, according to National Weather Service observations at Bellingham International Airport – including a record high 62 degrees on Jan. 17.
Greatest danger of flooding was along the Nooksack River, which is running within a few feet of flood stage in the foothills.
Gage height was 141.13 feet and steady Wednesday morning on the Nooksack near Deming, according to a USGS measuring station. Flood stage at the monitoring site is 146.5 feet.
For the Nooksack River at Ferndale, gage height was at 8.7 feet and slowly rising Wednesday morning, but the river was well below the minor flood stage of 18 feet.
Burg said the greatest threat of landslides was later in the week on steep hillsides and along coastal bluffs.