Rivers rising, expected to peak Monday through Tuesday

After an atmospheric river arrived Saturday night, the rain is continuing into Monday but it appears to be aimed toward the northern third of western Washington.

What happened to Seattle’s ‘Pineapple Express?’ Enter, the ‘atmospheric river’

However, there will be rain around even farther south from the heaviest rainfall areas.

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Snohomish County PUD

Forecast

Highs will again be mild, well into the upper 50s.

This batch of rain will produce 4-5 inches of lowland rain across the San Juans, Whatcom and Skagit counties as well as at the coast.

Farther south, there will be an Olympic Mountain rain shadow reducing rainfall totals around Everett down to near Seattle. Even parts of King County could see 1-2 inches of rain Saturday night through Monday morning.

The rivers across the area will spike up again, but the greatest rainfall will likely be in the North Cascades with 6-10 inches of rain.

As a result of that, the Skagit River at Mount Vernon will likely reach major flood stage Monday and Tuesday.

The other river systems farther south will rise, but should not approach the crests seen or that will mean the current system that moved out Friday.

Wind advisories are in effect through Monday for most of western Washington with wind gusts between 40 to 50 mph.

The winds will really pick up Monday afternoon along the strait and the northern interior.

Gusty winds today around the Pacific Northwest along with the rain. A Wind Advisory is in effect for most of Western Washington until midday Monday for wind gusts between 45-55 mph. @kiro7seattle #kiro7seattle #seattle #wawx pic.twitter.com/11IIMzIgLZ

— Claire Anderson (@ClaireKIRO7) November 14, 2021

Flooding

A flood watch will remain in effect through Tuesday for many area rivers as they continue to rise and peak through Tuesday evening.

With the threat of major flooding along the Skagit River, some people were told to evacuate the town of Hamilton on Sunday. An evacuation advisory was put in place, and the Red Cross is running an evacuation shelter out of Hamilton Baptist Church in Sedro-Woolley.

FLOOD UPDATE: A second emergency siren has sounded in Hamilton, urging residents to evacuate. By third siren, all residents should be at a safer location at higher ground. An emergency shelter at the Hamilton Baptist Church is scheduled to open at 5pm for those seeking shelter.

— Skagit County (@SkagitGov) November 15, 2021

The U.S. Army Corps of Engineers helped with local flood fighting efforts and activated its Emergency Operations Center in Skagit County.

An Army Corps team began work on Thursday, repairing an eroding segment of a Skagit River levee near Lions Park in Mount Vernon.

Anyone with questions or who needs sandbags can call the Skagit County Department of Emergency Management at 360-416-1850.

Skagit County residents were told to expect water over low-lying roads, particularly Swan Road, Whitmarsh Road in Burlington, Martin Road in Rockport and potentially Cape Horn.

River flood warnings with a major flood stage forecasted include: Skagit, Elwha, Skokomish, Nooksack, SF Nooksack, Cowlitz, Samish, Bogachiel, Snoqualmie, Skykomish, Snohomish, and Chehalis.

You can keep track of the rivers in your area here.

Next week outlook

The atmospheric river comes to an end Monday morning as a strong cold front moves into the area. This will bring lower snow levels to the Cascades and we could see some snow back to the passes Monday night into Tuesday.

Winds will still be breezy Monday as the cold front moves through. Winds will be strongest north of Everett and along the strait.

The great news is that we have an extended (albeit cold) break, from Wednesday through at least the end of next week. Highs will be hard-pressed to get to the mid-40s in the lowlands, with lows in the 20s and 30s.

We could see some of the coldest temperatures of the season Wednesday and Thursday mornings with widespread frost and some freezing temperatures.