Flood-ravaged communities of western Whatcom County braced for even more wind and rain this week as another “atmospheric river” — the fifth such storm this month — was poised to drop another multi-day deluge.
Both Everson and Sumas saw floodwaters again as the Nooksack River poured over its banks Sunday, Nov. 28, and reached Sumas on Monday, Nov. 29, according to officials in the two cities that were hardest-hit by flooding earlier in November.
And flooding could worsen as heavy rain is forecast across Western Washington from Monday night, Nov. 29, through Wednesday, Dec. 1.
Countywide damage was estimated last week at $50 million, and hundreds of residents were forced from their homes into temporary shelters.
Current data from the Northwest River Forecast Center shows the Nooksack River cresting before noon Monday as floodwaters headed downstream toward the river delta at the Lummi Reservation.
River levels were receding around noon Monday at measuring stations in Everson and near Nugent’s Corner.
Forecasts for the next several days show river levels rising to “action level” below flood stage on Wednesday in Nugent’s Corner and near moderate flood stage Wednesday night in Ferndale.
No forecast data was available for Everson.
“Current (forecast models) suggest lighter rainfall accumulations than what we experienced over the weekend, where portions of the Olympic Peninsula and (Whatcom/Skagit counties) generally saw 3-6 inches of rainfall accumulation,” said meteorologist Maddie Kristell in the online forecast discussion.
With the rain will be gusty south to southeast winds starting Tuesday afternoon, and tree damage and power outages were possible, the weather service said in statement.
Gusts of 30-35 mph were possible.
Monthly rainfall totals in Bellingham approached triple their normal levels, according to data from the National Weather Service in Seattle, and this new storm was expected to drop up to 1.5 inches of rain on the Whatcom County lowlands and 2 to 3 inches in the North Cascades.
“The big factor that will affect the scope of expected impacts will be how much of a break we receive in areas where river flooding continues (Monday),” Kristell said.
“As of (Monday) morning, the lower reaches of the Nooksack and Skagit rivers have yet to crest. It remains unclear how rivers in these areas will respond to additional rainfall over the next two days,” she said.
Some 1.17 inches of rain fell at Bellingham International Airport on Saturday, Nov. 27, and 1.63 inches fell on Sunday, Nov. 28.
Both measurements broke daily rainfall records from 1995.
For the month, 13.27 inches of rain had fallen through Sunday at the airport, against a November average of 5.2 inches.
Kristell said that the persistent rain means that an increased threat of landslides will remain for several days.
“Soils will not have adequate time to fully dry out, therefore they will remain unstable,” Kristell said.
Indeed, a landslide blocked part of northbound Interstate 5 south of Bellingham on Sunday, reducing traffic to one lane and creating long backups. The lane remained closed Monday, as WSDOT assessed the scene.