Snow and mountain weather next 8 days

Storm #2 delivered a few pockets of moderate snow accumulation including Crested Butte, Aspen Mountain, and Copper Mountain in Colorado.

Crested Butte 12/9/2021.
Copper Mountain 12/9/2021.

The main event for Utah and Colorado remains the 3rd storm system of the cycle. It’s currently exiting California and will move into Utah then Colorado between Thursday and Friday. On infrared satellite also notice the storm system sliding out of the Gulf of Alaska aimed at the Pacific Northwest.

Infrared satellite and storm track 12/9/2021.

This qualifies as a weak to moderate intensity atmospheric river setup. Heavy snow accumulation (30-50″) likely on the higher volcanoes and Cascades between Friday-Saturday. 8-12″ interior British Columbia and Banff Area.

This storm system and atmospheric river sinks south and hits California by Sunday night and continues Monday and Tuesday. Heavy precipitation totals are likely.

Integrated vapor transport for San Francisco, CA zone.

This storm system then breaks loose 12/14-12/15 and delivers snow to Utah, Idaho, Wyoming, Montana, Colorado, and New Mexico. The track of this storm system is still in question and will have important implications on snow accumulation.

Snow Forecast

Let’s look at my snow forecast in two timeframes.

Mid-mountain totals 12/9-12/12

Inches of snow 12/9-12/12.

Mid-mountain totals 12/13-12/17.

Inches of snow 12/13-12/17.

Drilling down, here’s my snow plume collective.

Inches of snow, mid-mountain.

Cold Morning 12/11

I’m also forecasting the coldest morning of the season so far in Colorado in the wake of this storm system. Let’s look at Saturday (12/11) morning.

12/11 5amGUSTS (MPH)AIR TEMP (F)
LONGS PEAK70-15
CRESTED BUTTE20-20
BERTHOUD PASS50-10
QUANDARY PEAK40-20
CAMERON PASS45-8
Tomer forecast 12/11 5am.

For more analysis here’s my forecast video:

Powder weekend ahead; storm system next week

Tomer’s Take

  • 1-2 feet of snow accumulation Thursday-Friday in Utah and Colorado.
  • Pacific Northwest atmospheric river (moderate intensity) delivers 25-60 inches Saturday to Baker, Rainier, Stevens Pass, Timberline, and Bachelor.
  • That atmospheric river then hits California Monday-Wednesday with potentially big totals. Forecast intensity is moderate.
  • Storm system hits Utah, Idaho, Wyoming, and Colorado next Tuesday-Thursday.

The current infrared satellite shows a minor low and major low. Also notice the low pressure near Hawaii. That becomes part of the atmospheric river setup this weekend into next week for the West Coast.

Infrared satellite and storm track 12/8/2021 5am.

Looking at next week, you can see the pressure anomalies Tuesday-Wednesday (12/14-12/15).

Pressure anomalies (500mb) 12/14-12/15.

I’ll break my snowfall forecast into two timeframes.

Mid-mountain totals 12/8-12/12:

Inches of snow 12/8-12/12.

Mid-mountain totals 12/13-12/16:

Inches of snow 12/13-12/16.

Drilling down, here’s my snow plume forecast for Crested Butte, CO.

Inches of total snow 12/8/2021.

My forecast video analysis:

Snow trends through Friday and next week

Tomer’s Take

  • 2nd storm system Wednesday-Thursday is minor and fast-moving.
  • 3rd storm system is the main event 12/9-12/10 with moderate to heavy snow accumulation in UT, CO, and northern NM. It’s a colder and windier storm system, which will help with snow efficiency.
  • Next storm system hits California with heavy rain/snow on 12/13-12/14 then moves into the Intermountain West 12/14-12/15.
  • This storm system could turn into an atmospheric river setup for California.
Infrared satellite and storm track, 12/7/2021.

Let’s look at storm #3. It’s the final storm of this cycle for the Intermountain West. Atmospheric pressures are forecast to run two standard deviations below the 30-year average. This means it’s strong.

Pressure anomalies (500mb) valid 12/10/2021.

Let’s look at my forecast snow totals in two timeframes.

Forecast mid-mountain totals 12/7-12/11:

Inches of snow 12/7-12/11.

Forecast mid-mountain totals 12/12-12/15:

Inches of snow 12/12-12/15.

Drilling down, here’s my snow plume forecast for Crested Butte.

Inches of snow over time. 12/7/2021.

For more analysis, here’s my forecast video.

Snow forecast this week across the West

Three storm systems are lined-up for the Intermountain West this week.

  • 1st storm system sacrifices itself to chip away at and dislodge the big high pressure dome.
  • 2nd storm system is minor and fast-moving.
  • 3rd storm systems is the main event. It’s also colder and windier.
Infrared satellite and storm track 12/6/2021 5am.

Snow Forecast

The first two storm systems help to establish a more favorable storm track for the the 3rd storm system to flourish.

Notice the big dip at jet stream level in the forecast image below. These strong winds and colder temperatures will increase the generation and efficiency of snowfall.

Jet Stream forecast valid 12/10/2021. GFS interpretation.

My wind gust forecast for the highest Western peaks reveals two surges. One surge occurs with the first storm system, and a second larger surge occurs with the 3rd storm system.

Tomer wind gust forecast (mph). 12/6/2021.

Here’s my snow forecast in two timeframes.

Snow totals (inches) between 12/6-12/8:

Inches of snow 12/6-12/8.

Snow totals (inches) between 12/9-12/12:

Inches of snow 12/9-12/12.

Let’s drill down a little more. Here’s my snow plume forecast for mid-mountain Park City, UT.

Inches of snow over time.

Snow (finally) for the West this week

2-3 different storm systems are lined-up for the Intermountain West through 12/11. The first storm system will lose strength battling the bulletproof area of high pressure. But, this greases the atmospheric skids for the final two storm systems. Notice the dipping storm track over Hawaii on this infrared satellite image. This is the pattern change headed for the West.

Infrared satellite 12/5/2021.

Snow Forecast

  • First storm system delivers light to moderate accumulations as it sets the storm track.
  • 2nd storm system is minor with light snow accumulations.
  • 3rd storm system is the main event. It’s also colder, which will help with snow efficiency and generation.

I put together an in-depth forecast video:

Tomer forecast video 12/5/2021.

My snow forecast is broken down into two timeframes.

Totals between 12/5-12/8:

Inches of snow 12/5-12/8.

Totals between 12/9-12/12:

Inches of snow 12/9-12/12.

Side Note:

My friend Cole (who’s also into the outdoors) put together this great Blog post and podcast after interviewing me. We talk about meteorology, my background, my professional work with mountaineerning and skiing teams around the world, television, 14ers, Kelso Ridge, and the changing landscape of Colorado.

Please give it a look and listen!

2-3 storm systems next week across the West

I started Saturday off with a trail run in the Foothills of Colorado. The weather here has been incredibly warm and dry the last two weeks.

Saturday morning run 12/4/2021.

I thought extensively about the mountain weather forecast for next week. My conclusions:

  • 2-3 storm systems possible across the West.
  • The first storm system becomes weaker and weaker as it battles this bulletproof area of high pressure.
  • The first storm system sacrifices itself and greases the atmospheric skids for potentially a 2nd and 3rd storm system.
  • The 3rd storm system could be the main event.
  • Snow forecasts will fluctuate wildly until the first storm weakens/dislodges the big high.
  • The best skiing might be late-week and weekend.

I recorded an in-depth forecast video. I include a two-part snow forecast so you can see how this might unfold next week.

Tomer forecast video 12/4/2021 11am.

Snow forecast next week across the West

2-3 different storm systems remain possible next week across the Intermountain West. The first storm system will likely lose strength and snow potential as it battles the massive high pressure ridge currently anchored over the West. This will create wild fluctuations in snow forecasts through this weekend.

You can see the storm track (yellow), high pressure ridge, and storm systems lined-up in the infrared satellite image.

Infrared satellite 12/3/2021 5am.

The first storm system essentially sacrifices itself to grease the atmospheric skids for the 2nd and potential 3rd storm systems.

Mid-atmosphere pressure anomalies valid 12/7/2021. GFS interpretation.

How likely is the 3rd storm system? The data is split. The 2nd storm system could absorb the 3rd and become a single larger storm system. Time will tell.

Snow Forecast

Let’s look at the long-range snow forecast in two timeframes.

My forecast snow totals 12/3-12/7:

Inches of snow 12/3-12/7.

Forecast totals 12/8-12/11:

Inches of snow 12/8-12/11.

Drilling down, let’s look at my snow plume forecast for Park City, UT and Jackson Hole, WY.

Inches of snow 12/3-12/11.
Inches of snow 12/3-12/11.
Tomer forecast video 12/3/2021.

2-3 storm systems next week

Confidence is growing for two storm systems next week across the Intermountain West. Could we see a 3rd storm system late next week? Yes there is some data to support that possibility.

Here’s the current setup on water vapor satellite. The red colors indicate drier air aloft. The primary storm track continues to favor the Pacific Northwest, British Columbia, and western Alberta.

Water vapor satellite 12/2/2021 5am. Red = drier air aloft.

Next Week

The first storm system on 12/6-12/7 will chip away and dislodge the big high pressure ridge currently across the West. This will grease the atmospheric skids for the 2nd storm system and possibly a 3rd by 12/10.

Pressure anomalies around 18,000ft next week. GFS interpretation.

Let’s look at snow totals in two phases. Totals between 12/2-12/5:

Inches of snow 12/2-12/5.

Totals between 12/6-12/10 (Assuming 3 Storm Systems):

Inches of snow 12/6-12/10.

I had a request for my Park City snow plume forecast (from Brett). 2-3 storm systems could deliver significant grand totals by 12/10.

Tomer Park City mid-mountain snow plume 12/2/2021.
Tomer forecast video 12/2/2021.

Next week’s storm system(s)

The high pressure ridge across the West is running three standard deviations above the 30-year average . This means it’s strong. But, a storm system (or two) next week will attempt to break it down. The current water vapor satellite continues to show very dry air across the Intermountain West (Red = Drier Air).

Water vapor satellite 12/1/2021 5am. Red = Drier Air.

Next Week

There are two storm systems lined-up for the Intermountain West between 12/6-12/10. This is good news because it will take more than one storm system to completely break down the high pressure dome.

Storm #1, 12/6-12/7:

12/6-12/7 500mb GFS pressure pattern.

Storm #2, 12/9-12/10:

12/9-12/10 500mb GFS pressure pattern.

How much snowfall? Let’s break this down into two timeframes again.

My forecast totals 12/1-12/6, click to enlarge:

Inches of total snow 12/1-12/6.

My snow forecast between 12/6-12/10, click to enlarge:

Inches total snow 12/1-12/6.

Let’s drill down a little more and look at Jackson Hole. Here’s my snow plume forecast 10 days into the future. You can see the effect of both storm systems.

Tomer snow plume forecast 12/1/2021.

What’s my opinion on both storm systems? It’s too early to get excited but at least there’s something on the horizon. I worry about the strength of the high pressure ridge. Two storm systems are required to do the job.

Snow forecast next 10 days across the West

The high pressure dome sitting across the West strengthened to three standard deviations above the 30-year average. This means that the next storm system will have a more difficult time breaking it down. Like I said yesterday, my gut says it might take two storm systems with the first being sacrificed to break the high.

Water vapor satellite 11/30/2021 5am. Red = Drier Air.

In the above satellite image I marked the storm track in yellow. The bullseye remains the Pacific Northwest, British Columbia, and western Alberta. This flow is actually so strong that it exceeds the threshold required to be a “moderate to strong atmospheric river”. Here’s the integrated vapor transport forecast (IVT):

When will snow return to the West? Yesterday I suggested on/around 12/7. That still looks accurate but the strength of the storm system is in question as it runs into a stronger high pressure ridge. In the end, it might be what’s behind this first storm system that really matters. In other words, what we need is a full storm cycle rather than a one-and-done.

Lower pressures possible across the West valid 12/7/2021. GFS interpretation.

As the storm track drops south so will the wind. Wind gusts on the higher peaks will start to increase late in the period.

Tomer wind gust (mph) forecast through 12/6.

Snow Forecast

The potential amounts of snow are trending down. Let’s look at this before the pattern change and after.

My snow forecast (inches) between 11/30 and 12/5, click to enlarge:

Total snow (inches) 11/30-12/5.

Total snow between 12/6-12/9, click to enlarge:

Total snow (inches) 12/6-12/9.
Tomer forecast video 11/30/2021.