Atmospheric river brings ‘a fire hose of moisture’ to Northwest

The official word on current weather?

“Gray and wet,” said Andy Bryant, a forecaster for the National Weather Service’s Portland office.

A so-called atmospheric river pounded the Pacific Northwest late this week, bringing with it heavy rains, wind and some flooding in the region. The phenomenon is so named for its terrestrial cousin: a long, narrow band of tropical moisture, a sort of air-bound river, that can carry serious rainfall.

“It’s a fire hose of moisture,” Bryant said.

Vancouver and Portland were on the southern edge of the system, Bryant said, so this part of the region wasn’t hit as hard as the coast or Puget Sound. A landslide that covered an unspecified portion of BNSF Railway tracks delayed passenger railway traffic until Sunday morning, and The Seattle Times reported that the Emerald City saw its rainiest day this decade.

Vancouver, meanwhile, received about 1 3/4 inches of rain over 48 hours as of Saturday morning. The rainfall record for Dec. 20 is 2.01 inches, set in 1925, and only 0.63 inch fell on the same day this year. Saturday also saw a small landslide of branches and debris on Highway 503 near Old Lewis River Road, which briefly blocked northbound traffic in the afternoon.

There may not have been any rain records here Friday, but Vancouver did tie the high-temperature record of 59 degrees.

“You should have been out in shorts and a T-shirt,” Bryant said.

The gloomy weather may have had you contemplating sunnier days, but here in Clark County, the week’s rains were needed. October and November were unusually dry, Bryant said, with below-average snowpacks in the Cascade Mountains.

“This was beneficial rain,” he said. “We’ve had a lot of rivers that have been pretty low, which hasn’t been great for salmon and other critters.”

As for Christmas Eve and Christmas Day, there’s a chance of sunshine, but mostly cool, cloudy days with temperatures in the low 40s and possible rain.