Dominant December High Pressure

Posted at 4:56 PM, Dec 02, 2020
and last updated 2020-12-02 20:47:36-05

An AIR STAGNATION ALERT has been issued for some of the valleys of western Montana for decreasing air quality.

What a beautiful Wednesday! More sunshine will occur over the next several days. The jet stream has lifted well north into Canada as a monster ridge of high pressure builds across western North America. This pattern will persist through the rest of the week, this weekend, and into next week. While skies will be clear for most of the state throughout the period, other weather conditions will differ. The valley of western Montana will have inversions which will trap colder air with calm wind conditions. The calm wind conditions will allow for a buildup of stagnant air which will decrease the air quality. Meanwhile the plains and higher elevations will be breezy with milder temperatures and fresh air. Overnight lows will also be much colder in the valleys than the plains. Changes are likely toward the end next week. Snow is possible for the second weekend of December.

Have a great day!

Curtis Grevenitz

Chief Meteorologist