Tomer’s Take: Moderate to heavy snow accumulation hits ID, MT, WY, UT, and CO 12/7-12/8 with light accumulation 12/10. Out East, a large, windy storm system pushes most ski areas into the warm sector with primarily rain on PM 12/10 changing to snow on 12/11.
My PM forecast video:
Current Setup
Water vapor satellite shows an active PNW flow with two areas of low pressure en route.
Orange/red = drier air aloft.
Forecast Jet Stream
Valid 12/8. This is the best shot of snow for the Interior Rockies. Notice the large trough over WY, CO. The 2nd storm system on 12/10 is much smaller.
Valid 12/10. Progressive, fast flow with light snow accumulation across the Interior Rockies.
Valid 12/15. Potential storm system development in SE CO/N NM. Confidence is low.
Eastern Storm System
Valid 12/10. Most big ski areas are on the warm side of the jet with rain initially then changing to snow on 12/11. This is a windy storm system.
Valid 12/10. Forecast radar/satellite shows mainly rain for the big ski resorts with snow on the colder, western side. Rain changes to snow at the ski areas on 12/11.
Forecast Radar & Satellite
Forecast Totals
*Updated 4pm 12/6.
UT Snow: 12/7-12/8.
CO Snow: Late 12/7-12/8.
WY Snow: 12/7-12/8, 12/10.
MT Snow: 12/7-12/8, 12/10.
*Updated 4pm 12/6.
Second storm system is lighter and faster but a few places squeeze out 4-5 inches.
*Updated 4pm 12/6.
Most of this accumulation in VT/NH/ME occurs on 12/11 after rainfall initially (on PM 12/10).
