Mild, rainy winter returns

The rain may be coming back, but El Nino isn’t going away.

Pacific Northwest weather is headed into a wet pattern starting today, according to the National Weather Service. After a relatively clear and mild period, the predominant westerly wind pattern over the Pacific Ocean has rebuilt itself and is ushering a series of storm systems into Western Washington.

The region is in for some rain over the next few days but none of it too severe, according to the weather service.

A cloud bank sweeping toward the Northwest looked menacing on a satellite photo Tuesday, but it won’t be as strong as it looked, said Danny Mercer, a meteorologist with the weather service in Seattle.

“It’s probably going to stretch out and weaken a little bit but we do have some light rain coming in during the day,” Mercer said of today’s forecast.

Over the next few days, “it’s going to be off-and-on rain. None of the systems look particularly heavy.”

Some snow is predicted for the Cascades, with about 3 inches expected at Stevens Pass, he said. High temperatures in Everett will be in the mid-to-high 40s, with lows in the low 40s.

Last month was the warmest January on record at Sea-Tac International Airport, and the forecast for the next month is warmer and drier weather than normal, according to the weather service. This is largely attributed to El Nino, a cyclical warming of the east part of the Pacific Ocean that upends weather patterns all over North America every few years.

The mild winter has been good news for anyone concerned about flooding — the coming rain isn’t expected to cause any problems, according to the weather service.

It hasn’t been good news, however, for the larger water picture in the Northwest. The lighter snowpack likely means lighter river flows this spring, which translates to less power generated from dams.

This is expected to result in a sharp drop in revenue for the Bonneville Power Administration, the federal power marketing agency.

The outlook still could change if more snow arrives than expected. But the current prediction by the National Weather Service calls for only about 74 percent of the 30-year average of water runoff.

If the forecast holds, the melting snow would produce the lowest runoff in the Northwest since 2001.

The Snohomish County Public Utility District gets about 80 percent of its power from the Bonneville Power Administration. A spokesman for the PUD said, however, that the light winter is not expected to affect its power supplies or rates this spring.

The PUD has made some short-term purchases of extra power to cover its bases, spokesman Neil Neroutsos said.

Water in the Sultan Basin, where the PUD operates its Jackson Hydroelectric Project, is about 85 percent of normal, he said. Still, this accounts for only 4 percent of the utility’s power.

“We don’t anticipate there’ll be any problems,” he said.

The Associated Press contributed to this story.

Bill Sheets: 425-339-3439; sheets@heraldnet.com.