10/21 update: Weekend mountain snow

Tomer’s Take:

• Pattern change underway. High pressure becomes dislodged.
• Two low pressure systems lined-up: 10/22-10/24 and 10/26-10/28.
• Bullseyes: Utah’s Wasatch especially Little Cottonwood, Colorado’s Western/Southwest mountains including Crested Butte, Purgatory, Silverton and Wolf Creek, Montana’s Big Sky and Bridger Bowl.

Current Setup

The long-standing high pressure ridge becomes dislodged and replaced by both low pressure systems 10/22-10/28.

Water vapor satellite shows the setup. Storm #2 is currently cut-off but will eventually be reabsorbed by the Polar Jet. Orange/red = drier air aloft.

What is a cut-off low? It’s simply not attached to the main jet stream flow. It’s spinning alone.

Storm #2 Pattern

Forecast mid-atmosphere pressure anomalies show the potential for a second trough 10/26-10/28.

Forecast Wind Gusts

Grand Teton	MPH
10/21	55
10/22	55
10/23	35
10/24	40

Kings Peak	MPH
10/21	35
10/22	65
10/23	45
10/24	30

Forecast Snow

Forecast radar/satellite valid 9pm Saturday 10/22.

Forecast radar/satellite valid 6am Sunday 10/23.

Forecast radar/satellite valid 9pm Sunday 10/23.

Forecast snow totals between 10/21-10/24.

Forecast snow totals between 10/26-10/28.

My forecast video: