Another round of mountain snow will blanket the Sierra Nevada and Cascades early this week.
The storm system can be seen moving across Oregon now with a cold front stretching southward into Northern California and out to sea.
This cold front will help spread cooler air southward into California and across the interior West early this week. Snow levels will lower to about 3,000 to 3,500 feet in the Sierra Nevada. Travel across passes, including Donner Pass, will be difficult through Monday evening.
Snow amounts will likely range between 1 and 2 feet in the Sierra Nevada and up to a foot in the Cascades and Bitterroots.
There is alot of energy moving through and plenty of cold air aloft. It will be unstable enough for some thunderstorms and hail across Northern and Central California Monday afternoon and evening. There will be adequate wind shear for some rotating thunderstorms and an isolated funnel cloud or tornado will be possible.
Winds will also be very strong across the mountains and High Desert in California and across southern Nevada into Utah. Winds can frequently gust between 45 and 55 mph with isolated gusts to 65 mph. This can create blowing dust and reduced visibility as well as down trees in the mountains and cause power outages.
The storm will be quick to leave Tuesday. Models show another upper-level shortwave coming through California and Nevada Wednesday to Thursday. This one does not look to be as strong but could bring some showers or spotty thunderstorms.
Looking at the GFS Ensemble 500 mb height anomaly a flatter pattern may set up between days 5 and 10 (Friday to the following Wednesday) which will not favor any major storms or warm or cold spells.