Pacific Will Unload Almost Two Feet of Rain on Northwest

(Bloomberg) -

In the next week, parts of the Pacific Northwest might get more than 20 inches of rain, more than San Francisco gets in an average year.

The culprit is a low-pressure system over the Gulf of Alaska flicking “streaks of energy” that land on North America’s coast as storms, said Brian Hurley, senior branch forecaster at the U.S. Weather Prediction Center in College Park, Maryland.

Storms already have wiped out a drought in the area around Seattle and in western Washington, according to the U.S. Drought Monitor, the result of a clash between the systems and the topography.

The rain is coming in a west-to-east motion and is hitting mountains running north to south, said Brad Rippey, a meteorologist with the U.S. Department of Agriculture. The peaks “are very efficient at wringing out the moisture,” he said.

A look at drought conditions in Washington makes this starkly apparent. The line at which the drought ends runs right along the Cascades.

More than 73 percent of the state is either abnormally dry or in some stage of drought, all within the central to eastern part of the state.

“It is a small geographic area being effected,” Rippey said.

Next week’s extreme rain will fall on the Olympic Peninsula, while Seattle itself will probably get about 3.5 inches through Tuesday, said Josh Smith, a National Weather Service meteorologist there. In a normal year, the city gets about 37.5 inches, 3 more than what it has received so far.

The rains aren’t going far enough south to reach California or pushing deep enough east to really roll drought back across the entire region, said Dave Simeral of the Western Regional Climate Center in Reno, Nevada. At best, California, in its fourth year of drought, may get a taste, Hurley said.

So when is California going to get some real rain?

Not now. Maybe later.

El Nino, the warming event in the equatorial Pacific that upends global weather patterns, is forecast to pump a steady stream of storms across California. That probably won’t happen for a few more weeks, however, Hurley said.

As always, even a train of heavy rains and snows isn’t likely to eradicate the deeply entrenched drought in California.

Maybe there is a glimmer of hope in all of this.

“It is encouraging to see some moisture coming in,” Rippey said.