Flooding fears linger ahead of another massive storm system heading toward Whatcom County

Ferndale averted major flooding Monday morning on a rain-swollen Nooksack River, after Everson and other upstream communities also saw minimal effects of high water on Sunday.

But more heavy rain is in the forecast and flooding remains a concern through midweek, the National Weather Service in Seattle said online.

“A more substantial atmospheric river arrives into the region late Tuesday and lingering through Wednesday. The favored locations for highest rainfall will be the Olympics and potentially the North Cascades,” meteorologist Maddie Kristell said.

“With snow levels continuing to remain high and rivers already running high, additional river flooding is possible. The threat of landslides will also remain elevated,” Kristell said.

Tuesday night’s storm is aimed at a broad area from the Olympics to Vancouver Island, forecasters said.

Exact rainfall totals for Whatcom County were unknown, along with how much snowmelt to expect from continued unseasonable warm weather. Bellingham could get one-quarter to one-half inch of rain from Tuesday through Thursday, according to a weather service briefing Monday afternoon.

“Continued uncertainty remains in the exact rainfall amounts into the middle of next week,” the weather service said. “Snowmelt is contributing to rises on rivers, but the extent of this contribution to water levels remains difficult to forecast. Washington rivers are highly sensitive to small variations in precipitation and snow levels. River forecasts are likely to change frequently.”

Estimates from the Northwest River Forecast Center showed a crest of 19 feet was expected before noon Monday in Ferndale, a measure that’s 1 foot above minor flood stage.

“The city has begun prepping for flood response and continues to closely monitor the river’s levels and will update the public if the forecasted levels change. In the meantime, please be patient on all roads, never drive over standing water where you can’t see the roadway underneath, and obey all road closure signs,” Ferndale officials said Sunday on Facebook.

Monday’s crest was at 18.52 feet, which caused minor flooding “with minimal impacts and road closures overall,” the city posted on Facebook about 11 a.m. Monday. “VanderYacht Park will remain closed until there is no more water flowing back into the river. Please continue to follow all road closure signs and never drive over standing water where you cannot see the roadway underneath.”

Hovander Homestead Park in Ferndale was closed as a precaution, and it would remain closed through Tuesday, the Whatcom County Parks and Recreation Department said in an emailed statement.

Slater Road was closed indefinitely between Ferndale Road and the Ferndale city limits because of water over the roadway, the Whatcom County Department of Public Works said Sunday in a statement.

In addition, water of the roadway forced closure of Hannegan Road between Polinder Road and the Lynden city limits.

In all, more than a dozen roads were closed or posted for restricted travel because of water on the pavement, according to Whatcom County’s website.

Everson was largely spared too.

”It looks like we’ve peaked at the point (in Everson),” Mayor John Perry told The Bellingham Herald in an interview late Sunday afternoon.

Perry said that Emerson Road was closed because of water over the road.

Main Street in downtown Everson saw minor flooding from backed-up storm drains and not overflow from the river, he said.

“Right now, Everson looks good. I don’t see any worries for Everson, Nooksack and Sumas,” he said.

Those three communities in northern lowland Whatcom County bore the brunt of heavy flooding on the Nooksack River in January-February 2020 and November 2021, a disastrous event that killed one man, displaced 500 people and caused more than $200 million in damage countywide.

Those storms were all caused by the same kind of subtropical atmospheric river of rain — known as a Pineapple Express — that drenched Western Washington last weekend.

A record 0.72 inches of rain for the date fell Saturday, followed by 0.76 inches on Sunday at Bellingham International Airport. On Sunday, the high temperature was 62 degrees, also a record for the date.

Such storms drop rain in the mountains, causing rapid snowmelt in the rivers and streams that flow out of the North Cascades.