Pattern through February 1

Tomer’s Take: A major low pressure (last of the atmospheric river) slides through UT/AZ/CO/NM next 24 hours with big totals. Then, the pattern shifts north with high pressure ridging over the Pacific Ocean and West Coast. The jet takes a NW orientation favoring PNW/BC/ID/MT/UT/WY/CO. By February 1, a trough might establish itself across the entire West with snow and cold.

Alta, UT is reporting 20 inches in the last 24 hours. That’s a 4-day total of 49 inches = about a foot a day. 423 inches for the season so far where they’re “Rolling in the Deep”.

Mammoth Mountain is reporting 11 inches in the last 24 hours. 378 inches for the season so far.

Season Totals So Far:

My forecast video 1/17:

Current Setup

Visible satellite shows a split jet with leftover AR moisture and a southern track low. It becomes a Panhandle Hooker storm system for CO/NM.

Forecast Pattern

Forecast jet stream valid 1/25. Notice the high pressure ridging off the West Coast and PNW. This flow favors Banff, MT, WY, northern UT, and the Central and Northern Mountains of CO.

February 1

Below is the EPS forecast atmospheric pressure anomalies (middle atmosphere) for late 1/31.

The high pressure ridge drifts West and a trough develops across the West. This type of pattern supports snow across the West.

Forecast Timing

Forecast radar/satellite valid 1/17-1/22.

Forecast Totals

Forecast snow totals (inches) valid 1/17-1/19.

Forecast snow totals (inches) valid 1/20-1/26. Notice the NW orientation of the snowfall/storm track.

Forecast snow totals (inches) valid 1/17-1/26. Central and Northern Mountains of Colorado:

Forecast snow totals (inches) valid 1/17-1/26. Most of this snow falls 1/19-1/20 and 1/22-1/23.