MOSES LAKE — A combination of cold air and even colder air will cause winds to start blowing and push temperatures to 25 to 30 degrees below zero in Grant County early Thursday morning.

Steven Van Horn, meteorologist with the National Weather Service office in Spokane, said Tuesday night that temperatures are forecast to be about seven to 10 degrees below zero early Thursday morning. But the winds will be blowing out of the north, forecast to be about 10 to 12 miles per hour.

“Those winds are going to have a significant impact,” Van Horn said.

The wind chill will knock temperatures down another 10 to 15 degrees.

Normally the wind blows when warm air and cold air interact, but in this case it’s cold with even colder air behind it.

Van Horn said a cold front initially caused temperatures to drop, and that has passed through. In this case it was followed by even colder air out of the Arctic regions, and that has had the same effect as cold air meeting warmer air. The really cold air brought with it some high pressure.

“It’s the strong high pressure that’s creating the strong (pressure) gradient,” Van Horn said.

It’s going to stay cold through Friday morning, he said, but temperatures will start moderating Friday afternoon into Saturday. But there’s precipitation in the forecast just as temperatures start to warm up.

The precipitation will start falling as snow, Van Horn said, but as it warms up there’s a chance of freezing rain. The chance for freezing rain could last into Christmas Day, when temperatures are forecast to start rising above freezing. Temperatures really are forecast to start moderating on Monday, he said.