Experts predicting warmer fall, winter for Western Washington

What’s been a delightful stretch of summer weather could give way to a warmer fall and winter than normal, at least according the National Weather Service’s long-range forecasting system.

“We’re potentially in for one of the warmest autumns in years,” says Cliff Mass, noted local meteorologist and professor of atmospheric sciences at the University of Washington .

Mass says we can credit “the blob” and El Nino.

“The blob” is a highly persistent area of warm water off the Northwest coast expected to remain in place for at least the next month or two, warming the air that comes our way.

The bigger factor that could impact our weather this winter is a developing El Nino, which would lead directly to temperatures 2-4 degrees warmer than usual from December through at least February.

“There is a decreased probability of having lowland snow that will mess up the streets in Seattle, and it also implies that the freezing level is higher in the mountains so we’ll probably end up with less snowpack by the end of the winter season.”

El Nino years also tend to restrict the formation of those Pineapple Express conditions that turn on the spigot of tropical rain from the south Pacific, Mass says.

“El Nino years tend to be less stormy, less windy, a little bit warmer. I don’t know if that will translate to much more sunshine, but definitely you’ll notice a difference,” Mass says.

But Mass reminds people there are no sure things in his business. Still, the models at this point paint a pretty compelling picture.

“Is a warm fall and winter guaranteed? Of course not. But the meteorological dice are heavily weighted in this direction,” he says.

Exterior photo courtesy KIRO Radio’s Ron Upshaw.