No surprise…more rain and upper-elevation snow is ahead for this Tuesday through Wednesday morning for portions of the Northwest US, as another disturbance enters the picture. Multiple strong storms over the Bering Sea along with a zonal flow in the jet stream will bring stormy weather to this part of the country.
During the daylight hours of Tuesday, precipitation will begin, enveloping most of Washington and Oregon. The heaviest of the rain will be in western Washington, where up to an inch of rain is forecasted to fall. The highest snow totals will also likely be found in the Washington Cascades. Up to two feet of fresh powder is expected to come down. Some snow is also likely for the Cascades of Oregon, but the accumulations will be lighter.
Significant snow accumulations will begin around 4,000 feet, according to the European model:
The rain and snow will move out of western Washington and Oregon, although a few lingering snow showers are possible for the mountains. All of this moisture will move into the eastern portions of the states, as well as most of Idaho and extreme western Montana. Idaho and the Bitterroots of Montana will now receive the brunt of the snow accumulations. A widespread 3-6 inches of snow is forecast for central, northern, and extreme eastern Idaho. Localized locations may receive up to one foot. This will definitely be a snow event for Idaho, with the exception of some rain in the valleys.
This disturbance will begin to wind down on Wednesday. The only areas that will still be dealing with any rain or snow will be portions of central Montana and the northwestern corner of Wyoming. This corner of Wyoming is going to see significant snow accumulations; up to a foot is forecast to fall on Wednesday morning. There won’t be as much in the way of snow for Montana, as it will be a bit too warm for it. During the latter half of Wednesday, a few rain and snow showers may move across eastern Montana, northern Wyoming, and the Dakotas.