An Arctic jet stream headed for the Inland Northwest is expected to start chilling things today. But just wait.
“The real punch will come Sunday,” said John Livingston, head meteorologist for the National Weather Service in Spokane.
Overnight lows Sunday and Monday could drop to near zero, forecasters said.
Those would be the coldest temperatures so far this year.
Today’s high is expected to be in the mid-20s, with a low tonight near 10 degrees. That would be a shock after recent springlike weather.
There is some good news.
As cold as the forecast sounds, the Arctic air should lose some of its bite before it moves into the region. The worst of the cold is expected to remain east of the Rocky Mountains.
A weak weather disturbance is expected Sunday along with the cold. But it is developing over land and won’t have much precipitation, Livingston said.
Snow flurries are possible today and Sunday, but no large accumulations are expected. More snow may fall to the west and south.
Winds of 20 to 25 mph, with higher gusts, will send wind-chill factors as low as minus 35.
The cold weather is caused by a shift in the upper-level winds, or jet stream.
For the past month, the region has been spoiled by a flow from the southwest with rain and sunshine.
That air flow has migrated west, sending the mild air into Alaska. The Inland Northwest is getting the return flow out of the north.
The cold weather is expected to last at least through the middle of next week.