Christmas Eve forecast backs off extreme windstorm; gusts still possible in Eastern Oregon

Forecasters are tracking Christmas Eve winds across much of the Pacific Northwest that could bring down trees and power lines.

But predictions have tempered since early in the week. By Wednesday morning, National Weather Service forecasters said wind gusts exceeding 60 mph in northwestern Oregon were unlikely.

“The low pressure system is coming in weaker,” Portland meteorologist Noah Alviz said. “It’ll still be breezy, but it won’t be like a historical wind storm.”

Around 11 a.m. Wednesday, much of northwest Oregon remained under a wind advisory, meaning winds could be strong enough to bring down some unsecured Christmas decorations, and people should remain cautious while driving.

Forecasters had a higher-level wind warning issued for parts of northeastern Oregon along the foothills of the Blue Mountains. That means sustained, strong winds are likely and people should stay inside.

Driving could be more treacherous on this side of the state.

“The atmospheric pressure over on their side is changing more rapidly than over here,” Alviz said. “And when the pressure changes more rapidly, you get stronger winds.”

Alviz said gusts could reach up to 75 mph in that region. The warning is in effect until 2 p.m. Wednesday.

People should still watch for downed trees, power lines

Although widespread damage isn’t expected in northwestern Oregon, Alviz said, winds could still pull down trees and power lines.

“Given all the rain we’ve had, the soils are saturated, so it’s not going to take much of a wind to knock down some trees, especially if a tree is already weak or dying,” Alviz said.

Josiah Vick, an arborist with PDX Tree Service, agrees.

“When soils are saturated, like they are right now, trees don’t usually fail just because of wind alone,” he said. “It’s a combination of wind and weakened root support that creates the risk.”

He says trees fed by a gutter off the roof or those that sit in a depression in the ground are more likely to get lots of water and therefore have shallower roots.

“Those ones seem to be the ones that are most susceptible to wind throw or bad conditions.”

Vick is expecting a busy next few weeks, even if the storm only brings winds of 40 mph. “Normally, the [calls] that we respond to first are trees that are down on a structure and they’re blocking access,” he said.

“If there is a problem where the tree is on a power line, the best thing to do is call PGE, not call your local arborist. We can’t do anything at that point.”

If there’s a downed power line on a car, authorities recommend calling 911 rather than getting out of the vehicle.

Oregon Department of Transportation said maintenance crews are preparing while still recovering from the recent storms. For safety reasons, crews do not clear fallen trees while winds are still high. Cleanup starts once conditions improve.

ODOT said its crews will be working day and night through the holiday. Travelers are asked to give them space and patience as they work to keep roads open and ensure people can reach their holiday destinations safely.