Tomer’s Take: A powerful atmospheric river remains on track for the West through 1/4. Grand totals of 1-5 feet (or more) for PNW, BC, CA, UT, WY, and CO.

-> See below for my forecast grand totals and snow timeline for the Wasatch.

My forecast video 12/27:

Current Setup

Infrared satellite shows the storm track reaching all the way back to Hawaii. This is the Pineapple Express.

Forecast Pattern

Forecast jet stream valid 12/30 continues to show an impressive west-to-east conveyor belt of moisture slamming into the West like a firehose.

Forecast Timing

Forecast snow totals (inches) valid 12/27-1/1.

Forecast Totals

Forecast snow totals (inches) valid 12/27-12/29.

Forecast snow totals (inches) valid 12/30-1/4.

Forecast grand totals 12/27-1/4:

Mammoth Mountain, CA: 99″

Tahoe/Palisades/Kirkwood/Heavenly: 68″

Alta, UT: 70″

Wolf Creek, CO: 53″

Crested Butte, CO: 47″

Aspen/Snowmass, CO: 34″

Jackson Hole, WY: 31″

Snow Timeline for the Wasatch:

• 12/27: 11″
• 12/28: 11″
• 12/29: 1″
• 12/30: 15″
• 12/31: 15″
• 1/1: 10″
• 1/2: 1″
• 1/3: 1″
• 1/4: 4″

Forecast snow totals (inches) valid 12/27-1/4.

Tomer’s Take: Data continues to suggest a “strong to extreme” intensity atmospheric river (AR) 12/27-1/4 for most of the West. Grand totals (see below) of 1-5 feet or more.

My forecast video 12/26:

Current Setup

Water vapor satellite shows the organizing atmospheric river reaching all the way into the western Pacific. This is the Pineapple Express.

Forecast Pattern

Forecast jet stream valid 12/30. Very impressive west to east jet stream pattern acting like a conveyor belt for the moisture. The jet reaches west beyond Hawaii.

Forecast Timing

Forecast radar/satellite valid 12/26-12/31.

Forecast Totals

Forecast snow totals (inches) valid 12/26-12/28.

Forecast snow totals (inches) valid 12/29-1/4.

My forecast grand totals 12/27-1/4:

Alta, UT: 64″

Jackson Hole, WY: 29″

Aspen/Snowmass, CO: 32″

Crested Butte, CO: 54″

Silverton, CO: 48″

Wolf Creek, CO: 46″

Mammoth Mountain, CA: 91″

Heavenly/Tahoe/Palisades/Kirkwood: 71″

++++++++++++++++++++++++++++++++++++++++++++

Key Snow Timeline for Wasatch:

• 12/27: (PM) 14″
• 12/28: (AM) 10″
• 12/29: (PM) 2″
• 12/30: 12″
• 12/31: 12″
• 1/1: 12″
• 1/2: 1″
• 1/3: 1″
• 1/4: 1″

Forecast snow totals (inches) valid 12/26-1/4.

Tomer’s Take: A major atmospheric river (AR) pattern hits the West with big snow totals 12/27-1/3 with 4-5 distinct waves of moisture. A larger storm system hits the Northeast on 1/1 but it appears to be mainly rain.

My forecast video 12/25:

Current Setup

Infrared satellite shows the organizing atmospheric river over the Pacific. Areas of low pressure are lined-up to deliver the moisture.

Atmospheric River Intensity

Data suggest a prolonged AR with intensity pegged early at strong to extreme on 12/27. The moisture feed lasts through 1/3.

Forecast Pattern

Forecast jet stream valid 12/30 illustrates the reach and fetch of this AR. This is the Pineapple Express.

Forecast Timing

Forecast radar/satellite valid 12/25-12/30.

Forecast Totals

Forecast snow totals (inches) valid 12/25-12/27.

Forecast snow totals (inches) valid 12/28-1/3.

Key snow timeline for the Wasatch:

• 12/27: 6-12″
• 12/28: 6-12″
• 12/29: 6″
• 12/30: 6″
• 12/31: 4″

Forecast snow totals (inches) valid 12/25-1/3.

Tomer’s Take: A ‘strong to extreme intensity’ atmospheric river arrives on/after 12/27 through 1/3 across the West with big snow totals. Out East, it’s cold and windy in the wake of the Blizzard with lake effect snow.

I snapped this aerial photo of the Eastern Plains of Colorado on Friday 12/23. It looks like the moon with wind-blasted snow and inverted temps around zero.

My forecast video 12/24:

Current Setup

Infrared satellite shows the organizing atmospheric river (AR) in the Pacific. The moisture fetch extends to Hawaii.

Forecast Pattern

Forecast jet stream valid 12/30/2022. Powerful west-to-east jet stream delivers heavy precipitation. The rain/snow line has to be watched.

Let’s zoom out. Forecast jet stream valid 12/30/2022. This paints a very clear picture as to what we’re dealing with: Pineapple Express. The jet acts like a moisture conveyor belt.

Forecast Timing

Forecast radar/satellite valid 12/24-12/29.

Forecast Totals

Forecast snow totals (inches) valid 12/24-12/26.

Forecast snow totals (inches) valid 12/27-1/1. This represents the heart of the atmospheric river.

Key days for biggest accumulation in the Wasatch:

• 12/27: 4″
• 12/28: 6″
• 12/29: 6″
• 12/30: 6″
• 12/31: 6″
• 1/1: 1″+

Forecast snow totals (inches) valid 12/24-1/1.

Tomer’s Take: Looking ahead, a moderate to strong intensity atmospheric river hits the West Coast on/after 12/27 through 1/1 with 3-4 different waves of rich Pacific moisture. Big totals likely.

Big low in the Northeast continues:

Strong wind, snow, rain, then back to snow for VT, NH, and ME. For example, Killington is reporting strong wind, 7″ of new snow, and 38 degrees.

Current Setup

Infrared satellite shows what’s organizing in the Pacific. I oftentimes refer to this as the Pineapple Express. Snow levels on/after 12/27 will be a concern.

Forecast Pattern

Forecast jet stream valid 12/31. Notice the west to east jet stream. Jet level wind reaches back to Hawaii acting like a conveyor belt for a firehose of moisture.

Forecast Timing

Forecast radar/satellite valid 12/23-12/28.

Forecast Totals

Forecast snow totals (inches) valid 12/23-12/25.

Forecast snow totals (inches) valid 12/26-12/31. This is the heart of the atmospheric river for the West.

Key powder days for the Wasatch:

• 12/27: 6″
• 12/28: 4″
• 12/29: 6″
• 12/30: 6″
• 12/31: 4″+

Forecast snow totals (inches) valid 12/23-12/31.

Tomer’s Take: The Western Arctic front races east and develops into a deep area of low pressure over the Great Lakes. It flushes the ski areas of VT, NH, and ME with warm air and mixed precipitation. Out West, Arctic air lingers with a moderate to strong intensity atmospheric river (AR) on/after 12/27.

My forecast video 12/22:

Current Setup

Denver hit -24F this morning – it’s 3rd coldest air temperature on record. Denver hit 50 for the high temp on Wednesday and dropped below zero in less than two hours when the Arctic front arrived.

Alta, UT is reporting 5″ in the last 24 hours.

Jackson Hole, WY 2″ in the last 24 hours.

Loveland, CO 5″ in the last 24 hours. Wind gusts are reaching 80mph generating wind chills to -40 to -60F.

Winer Park, CO 8″ in the last 24 hours.

Forecast Pattern

Forecast jet stream pattern valid 12/30. A moderate to strong intensity AR is possible.

Forecast Timing

Forecast radar/satellite valid 12/22-12/27.

Forecast Totals

Forecast snow totals (inches) valid 12/22-12/24.

Forecast snow totals (inches) valid 12/25-12/27.

Forecast snow totals (inches) valid 12/28-12/31. The AR delivers big totals to the West.

Forecast snow totals (inches) valid 12/22-12/26.

Tomer’s Take: An Arctic front is diving south through MT, WY, and CO driving the snow accumulation. This Arctic front then moves east and develops into a deep area of low pressure for the Great Lakes and Northeast. Unfortunately, the track puts the ski areas of VT, NH, and ME in the warm sector with a mix of precipitation. On/after 12/27 the West could see a moderate intensity atmospheric river.

My forecast video 12/21:

Forecast Timing

Forecast radar/satellite valid 12/21-12/26.

Forecast Snow Totals

Forecast totals (inches) valid 12/21-12/23.

Forecast totals (inches) valid 12/24-12/26.

Forecast totals (inches) valid 12/27-12/30.

Forecast totals (inches) valid 12/22-12/26.

Tomer’s Take: An Arctic front racing north to south from Canada will drive the Western snow pattern through 12/22. Then it moves East and develops into a strong, deep area of low pressure over the Great Lakes. But, it puts the big NE ski areas in the warm sector with a mix of precipitation. Long term, the West Coast might be setting up for an atmospheric river.

Current Setup

Water vapor satellite shows a deep trough over the Central Pacific including Hawaii. This may help develop a future atmospheric river on/after 12/28 for the West Coast. Also, notice the Arctic front diving south through the Intermountain West.

Orange/red = drier air aloft.

Forecast Pattern

Forecast jet stream valid 12/22 for the East. The Western Arctic front develops into a powerful area of low pressure with strong wind and heavy snow across the Great Lakes. Blizzard warnings are possible. Unfortunately, the track of the low puts most of the VT, NH, ME ski areas into the warm sector with a mix of precipitation.

Forecast jet stream valid 12/25. This N-S jet stream favors the PNW, BC, Banff, MT, ID, WY, northern UT, C+N CO.

Forecast jet stream valid 12/29. Fascinating pattern by 12/28-12/29 with big potential for heavy snow. This could be a moderate intensity atmospheric river (AR) for the West Coast.

Forecast Timing

Forecast radar/satellite valid 12/20-12/25.

Forecast Totals

Forecast snow totals (inches) valid 12/20-12/22.

I added Powderhorn Ski Area, CO to the map.

Forecast snow totals (inches) valid 12/23-12/25.

Forecast snow totals (inches) valid 12/26-12/29.

Forecast snow totals (inches) valid 12/20-12/26.

I added Hunter Mountain Ski Area, NY to the map.

My forecast video 12/20:

Tomer’s Take: The place to be through Christmas is the PNW, BC, Banff, ID, MT, WY, UT, CO where an Arctic front will direct the pattern. In the Northeast, the Western Arctic front develops into a large low pressure on/around 12/23. Unfortunately, it looks too warm with snow to rain then back to snow.

My forecast video 12/18:

Current Setup

Visible satellite shows a quiet Western pattern for now. Notice the blue Arctic front diving south from Canada. That front then connects to the large low pressure over the Pacific.

Forecast Pattern

Forecast jet stream pattern valid 12/19. The Arctic front is diving south from Canada.

Forecast jet stream pattern valid 12/25. Notice the N to S jet stream from the upper reaches of Canada through MT, WY, and CO.

Forecast Timing

Forecast radar/satellite valid 12/18-12/23.

Forecast Totals

Forecast snow totals (inches) valid 12/18-12/20. Arctic front starting to make its move south.

Forecast snow totals (inches) valid 12/21-12/23. Arctic front drags snow North to South with high ratios.

Forecast snow totals (inches) valid 12/24-12/27. NW flow type setup favoring Banff, BC, MT, ID, WY, UT, and Central & Northern Mountains of Colorado.

Snow returns to California on/around 12/27.

Forecast snow totals (inches) valid 12/18-12/26. The bulk of this snow occurs on/around 12/23 but will be mixed with rain.

Tomer’s Take: The next storm system for the Northeast arrives on/around 12/23 but might be too warm with rain initially then snow.

>Out West, an Arctic front 12/20-12/22 spreads snow north to south through ID, UT, MT, WY, CO.

>Then a NW type flow develops 12/23-12/26 favoring WY, ID, MT, CO, PNW, BC, Banff.

• Killington is reporting 22″ in 24 hours.
• Sunday River is reporting 22″ in 24 hours.

My forecast video 12/17:

Current Setup

Water vapor satellite shows a quiet period for the West. It turns more active on/after 12/20 with an Arctic front.

Orange/red = drier air aloft.

Forecast Pattern

Forecast jet stream valid 12/17/2022. A quiet period for the West.

Forecast jet stream valid 12/25/2022. A NW type flow develops 12/23-12/26 favoring PNW, BC, Banff, MT, ID, WY, CO.

Forecast Timing

Forecast radar/satellite valid 12/17-12/22.

Forecast Totals

Forecast snow totals (inches) valid 12/17-12/19.

Forecast snow totals (inches) valid 12/20-12/22. An Arctic front drags snow north to south.

Forecast snow totals (inches) valid 12/23-12/26. A NW flow develops forcing snow through PNW, BC, Banff, ID, MT, WY, CO.

Forecast snow totals (inches) valid 12/17-12/22. Most of this accumulation occurs as residual snow from the big snowstorm 12/16-12/17. Lake effect is also likely 12/18-12/19.

Forecast snow totals (inches) valid 12/23-12/26. A large storm system hits on/around 12/23, but it might be too warm with rain initially then snow.