Forecasters warn flooding possible in Whatcom, Skagit counties as warm storm system arrives
Heavy rain is forecast across Western Washington this weekend, prompting an alert about flooding on the Nooksack River in Whatcom County.
This weekend’s storm arrives as temperatures begin to warm and snow levels rise to 9,000 feet, meaning rain instead of snow is forecast across the North Cascades. Such scenarios can create the same conditions that were blamed for flooding along the Nooksack River in November 2021, the National Weather Service said in a “hydrologic outlook” warning issued Thursday.
“While uncertainty with respect to flood potential at individual river points remains high, confidence in heavier rainfall setting up across the mountains of Whatcom, Skagit and Snohomish counties has increased. If the middle to high end forecast rainfall amounts occur, minor flooding is possible on rivers draining from the Cascades in these areas,” the weather service said.
As of Thursday afternoon, estimates from the Northwest River Forecast Center show the Nooksack River cresting well below flood stage along the north and south forks — at Nugents Corner and at Ferndale.
Saturday looks to be the wettest day, with rainfall totals of 2 to 3 inches in the mountains and about a half-inch in the lowlands, the weather service said.
This weekend’s storm will be packing breezy south winds of around 30 mph, not strong enough for warnings, the forecast said.
Avalanche danger is “moderate” the mountains of Whatcom and Skagit counties, according to the Northwest Avalanche Center.
“Glide avalanches have occurred in the last few days around the Mount Baker backcountry and likely other areas in the zone as well. Avoid traveling on or below steep areas where you see gaping cracks in the snow, or in common glide locations where snow is coating smooth rock slabs or grassy slopes,” the avalanche center said online.
A glide avalanche is the process of an entire snowpack sliding as a unit, according to the U.S. Forest Service’s National Avalanche Center.
This story was originally published December 6, 2024 at 5:00 AM.
