West pattern transition; What about late November?

Tomer’s Take:

• Pattern transition underway for the West.
• Currently a weak low is sliding south from the PNW to CA. It’s headed to NM and southern CO as a southern track low through 11/14.
• This low opens the door for a large trough to develop across the Intermountain West (MT, WY, CO) with a stiff northerly flow from Canada through 11/19.
• The PNW/BC/West Coast gets a large ridge of high pressure through 11/19.
• What’s beyond 11/19? Data is mixed but the PNW could turn slightly more active.
• Bottom line: No big storm cycles on the horizon.

Current Setup

Infrared satellite shows the storm track, weak low pressure in the PNW sliding south, a second low headed for AK/Canada, and a high pressure that will become the dominate feature for the PNW/West Coast through 11/19.

November 12-19

Forecast jet stream flow 11/14. Notice the weak low sliding south through CA with light snow accumulation. Behind it a large ridge of high pressure amplifies the jet stream. This in turn sends it south through MT, WY, CO with colder air and fast-moving cold fronts and light snow chances.

Forecast jet stream flow valid 11/17. Big dip in the jet continues for MT, WY, CO.

Forecast jet stream flow valid 11/19. PNW/BC/West Coast high pressure ridge remains strong.

Late November?

Below is one possible pattern valid 11/24/2022. It shows a slight preference for lower mid-atmosphere pressures in the PNW/BC. Higher pressures are possible for parts of the Intermountain West.

This would mean most of the snow/colder temps are in the PNW/BC.

Forecast Timing

Forecast radar/satellite valid 11/12-11/17.

Forecast Snowfall

Forecast snow totals (inches) valid 11/12-11/15.

Forecast snow totals (inches) valid 11/16-11/19.

My forecast video 11/12: