Atmospheric River May “Trigger Flooding and Mudslides” This Week
Folks in the Pacific Northwest should stock up on groceries and essentials, and plan to spend the next few days hunkered down at home, as a series of atmospheric river events is expected to bring “a deluge of moisture” to the region, warned AccuWeather in a new report. Meteorologists say there is a serious threat of “blustery” weather conditions, including flooding, mudslides, and mountain snowfall.
RELATED: The #1 Sign Your Region Is About to Get Its First Hard Freeze.
The Northwest is recovering from last Sunday’s storm, which brought buckets of rain and high-elevation snow. But this weekend’s storm will “feature a more tumultuous pattern across the West,” including “additional waves of rainfall,” per AccuWeather.
The forecast shows multiple storms—what experts are calling an “atmospheric river”—slamming the region between Thursday and Sunday.
As Best Life previously explained, “An atmospheric river describes a weather pattern in which heavy moisture flows into a concentrated area.” The Northwest is no stranger to unpredictable rainstorms and wind gusts. However, in some instances, the effects can stretch into Southern California. And ’tis the season!
“Atmospheric Rivers are most common from November to January in the Northwest into Northern California. They also usually dump heavy rain in a short time period; within 24 hours, several inches can trigger flooding and mudslides,” explained AccuWeather senior meteorologist Chad Merrill.
The first atmospheric river of the season can hit Washington, Oregon, and Northern California as early as tonight, Wednesday, Oct. 22. “The upcoming late-week and early weekend storm will likely be no exception to that rule,” warned Merrill.
Starting tonight, sporadic rain showers and breezy conditions are expected to hit the coasts of southwest British Columbia, Canada, Washington, and parts of northern Oregon. But on Thursday, “a potent storm will follow in quick succession,” triggering coastal wind gusts upwards of 50 miles per hour and inland gusts reaching 30-40 miles per hour.
Rainfall totals will range from one to six inches, depending on the zone. The interior Northwest will only gain about two inches, while the coasts of Washington and Oregon, as well as the Cascades, can see up to four inches. Areas reeling from frequent rain could accumulate up to half a foot.
“The pattern setting up along the Northwest to Northern California coast is indicative of an Atmospheric River as the moisture can be traced back to Southeast Asia. This type of a pattern typically yields heavy rain and flooding with only very high-elevation snow in the Sierra given the warm air bleeding into the storm,” explained Merrill.
At a glance, the rain will be a welcome reprieve from the warmer-than-average temperatures and drought conditions the Northwest has been grappling with as of late. However, it also sets the stage for potential flooding and mudslides, which could be felt south into Northern California. All the above will likely hinder travel plans both on the ground and in the sky.
All of this to say, this weekend is the perfect time to bake all your favorite fall recipes, have a scary movie marathon, and catch up on your shows.