Atmospheric river setting up over Idaho

There is a giant plume of subtropical moisture off the coast of California. It’s being pulled north by a persistent low pressure center off the Oregon Coast. The combination of these two features with help to pump a lot of moisture over Idaho in the days to come. Because the subtropical air is warm, it will drive temperatures upward and that means any snow that falls in the valley, could quickly change over to rain. The plume of moisture will be in place for several days. Here’s how everything should play out.

WEDNESDAY: We could see early morning snow in the Treasure Valley. However, the snow will likely change over to rain or a wintry mix by mid-morning. Highs will reach the low 40’s. The mountains will easily see another foot of snow by the end of the day.

THURSDAY: Look for periods of rain in the valley with snow levels rising over the mountains. I do have a little concern that if we get rain falling on snowpack, we could see a rapid rise of some rivers and streams. This is something we’ll be on the lookout for.

FRIDAY: A cold front will sweep through the area and return us to a north flow. That means temperatures will get colder and we could see a return to some snow showers in the valley with more snow in the mountains.

THE WEEKEND: The models are suggesting drier air will gradually return this weekend to the valley, but, the mountains could still see a few snow showers. Highs will gradually return to the 30’s.

In summary, it’s going to be a soggy week for much of the state. The snowpack will continue to increase. The skiers will be in hog heaven. The farmers are giving each other high fives. Water is a good thing. I just hope it stays under control.