A Little Bit Of Everything With More On The Way

TL;DR:

    If you can't decide what weather you want this weekend you're in luck, while temperatures will be high through the beginning of the weekend, they will drop and snow will begin falling on Sunday.

Nowcast:

    Good morning from the mountains, if you find yourself venturing out today expect higher temperatures. Currently at the mountain bases temperatures are breaking freezing and reaching up to 35 °C. Ridgeline temperatures are sitting right around freezing with strong Southerly winds reaching into the upper 40s.

Alta

Short term:

    For your holiday weekend expect a little bit of everything. Throughout the day today temperatures will be high and the sun will be shining. As we sit under a ridge of high pressure our next storm is brewing off the West coast. Steadily throughout the weekend temperatures will creep back down with freezing levels dipping down into the valley by mid-day Sunday. Saturday night the flurries will begin and will intensify through the day. Models are calling for an additional 1.5" of water to fall by mid-day Sunday. With the continued cooling we can expect this storm to result in a right-side-up addition of 15" of pow! Snow will continue through Sunday evening and taper off through the night.

University of Utah Department of Atmospheric Science

Long term:

    If you're unable to make it to the mountains to enjoy the powder this weekend, fear not as there is more snow on the way! Following this weekend's storm, there will be a second effort beginning Monday night and lasting through the day Tuesday. Bellow this weekend's storm can be seen highlighted in green and the storm for the beginning of next week is highlighted in blue.

If you plan to travel in the backcountry ensure you are properly equipped with the right equipment. Know before you go, for all things avalanche and a full avalanche forecast check in with our friends over at the Utah Avalanche Center.

Round n is done. Round n+1 on the way.

TL;DR: 

The storm has passed, for now. Clear skies today and tomorrow, with another storm coming in this weekend. The active pattern that has produced so much snow over the past 30 days shows little signs of stopping. Alta is currently the snowiest ski area on planet Earth; it's a great time to forecast weather and ski in Utah!

Nowcast:

Bluebird day in the mountains today. Below is the cam from Alta. Probably feeling a little FOMO if you're sitting at your desk like I am today.

Webcam view of Mount Baldy. Courtesy: Alta Ski Area

I expect temperatures to remain below freezing throughout the day, with low to moderate winds. As I said, a great day to be skiing...

Short-term:

Not too much to write about from a short-term standpoint. Weather will remain clear throughout today and tomorrow. The main concern from a skiing standpoint is the temperatures tomorrow. I expect the mountain base to be above freezing, with near-freezing temperatures at mountaintop. Below is a GFS time-height plot at Alta. The blue line in the figure represents the freezing level; you
can see it gets well above the town of Alta. 

GFS Time Height plot at Alta, UT. Courtesy: UofU ATMOS

Long-term:

Later this weekend, we will get another system that will impact the state. This system looks to be eaten up more by the Sierra Mountains than the one earlier this week, but we could still get some solid accumulation. This system will be followed by 2 more pulses of moisture, both weaker than the first. 

The real question will be how much moisture can sneak by the Sierras. We will have a better picture later in the week. This uncertainty is expressed in the ensembles; the spread is around 35 inches for this first storm. I put a vertical red line in the figure where I suggest the transition is between the storms.

NAEFS ensemble snow accumulation for Alta-Collins. Courtesy: UofU ATMOS

Based on the ensemble, it's really up in the air with regard to what accumulation we can expect. A moderate amount (15 inches) is likely (90% chance), as only a few members produce less than 15 inches. Look for forecasts tomorrow and Saturday to get a more accurate picture of how much we can expect. 

In the final frames of both the GFS and European Model runs, a blocking ridge shows up over the Eastern Pacific. This is too far out to really be concerned about, but there is a possibility of a pattern shift...

Can't Stop, Won't Stop

TL;DR:

Snow tapers off this afternoon with the potential for another significant storm impacting the state of Utah this weekend. Objective metrics are telling us that conditions truly are all-time in the Wasatch; These are the winters that change lives.

Nowcast

Lingering snow showers should taper off by the end of the day. It's chilly out with temperatures ranging from the mid-20s at the base of Park City to 20F at the base of Alta at 9,000' to 11F at 11,000' on Mount Baldy. Winds have been strong all day, gusting to 79 mph on Mount Baldy with sustained winds in the 25-30 mph range on the highest ridgelines.

Looking down Little Cottonwood Canyon. Image courtesy of Alta Ski Area.

Storm Totals since Monday AM

Alta - 38 inches

Snowbird - 36 inches

Park City Mountain Resort - 31 inches

Deer Valley - 35 inches

Solitude - 37 inches

Brighton - 37 inches

Short-term Forecast

A ridge of high pressure will quickly build in above Utah tomorrow through Friday before a landfalling Atmospheric River in California brings cloudier weather to our region. Expect dry conditions through the end of the day Friday. Hopefully, this will give some time for everyone to dig out and for roads to reopen (looking at you LCC).

GFS Model 500mb Geopotential Height and Anomaly valid 00Z Friday January 13 (5pm MST Thursday January 12). Image courtesy of Tropical Tidbits.

Long Term Forecast
The potential for a set of two significant winter storms look to impact the state starting Saturday into Sunday. Look for more forecasts later this week to dive deeper into these systems. For reference, the GFS Little Cottonwood Canyon downscaled model for Alta-Collins shows one solution for potential snow.

GFS Little Cottonwood Canyon downscaled model for Alta-Collins. Image courtesy of the University of Utah, Department of Atmospheric Sciences.

Overnight snow with more on the way!

Nowcast:

It's currently 28F at the base of Alta. There are light winds from the southwest, but they are going to become stronger as the day continues. Alta is reporting 10" of new snow in the last 12 hours. The snow is slowly tapering off and should pick up again later today. 

Alta 12 hour snow stake, Alta.com

Short term: 

The storm started with a southwest flow in Utah yesterday afternoon, which will switch to a northwesterly flow early Wednesday morning. There is a small possibility for a break from snow this afternoon. Snow levels have been high throughout the night and will continue to drop as the storm develops. 

Tuesday at 10PM, U OF U ATMOS

The heaviest of the snow fell last night, but there is still more heavy snow to come. Through Jan 12th there is a 20% chance of 10 more inches and an 80% chance of 10+ more inches of snow coming to Alta Collins. 

Long Term:

After the storm this week there will be a ridge building over Utah for about 2 days. After the ridge it seems like an active pattern is coming to most of the west, including Utah this weekend. 

Ridge building over Utah.
Then an active pattern coming to most of the west.
 Pivotal Weather GFS

Backcountry comments:

If you will be traveling in the backcountry make sure you have the proper equipment and know before you go. For the whole avalanche forecast and all things avalanche head over to our friends at the Utah Avalanche Center.

More Snow You Want, More Snow You Get!

TL;DR:

    Snow, Snow, Snow. The snow is falling, will continue to fall, and powder will be skied. Buckle up for a wild week, the snow is going to fall through the start, take a break, and continue this weekend. Snow totals up to 30"!

Nowcast:

    If it's more snow you wanted, you are in luck. The snow is falling in the mountains with temperatures in the upper twenties dipping into the upper teens up around the top level. Ridgeline winds are blowing out of the South, and Southwest at around 30 mph. Snow will continue through today and into tomorrow. Snow totals of up to 18" are possible by tomorrow morning. 

Alta

Short term:

    Snow is the name of the game, and it isn't going to stop! Through the first half of this week, we will experience another significant snow event. The next few days will produce big time with the proper conditions, moisture, westerly flow, and cool temperatures. Models are showing areas of the Wasatch receiving astronomical water totals some even exceeding 3"! This could mean snow totals above 30", if you have some sick days, this might be a great week to get the powder fever.

University of Utah Atmospheric Science

Long term:

    Looking to the latter half of this week we are going to experience a brief recovery period prior to the next storm setting up to arrive this weekend. On the time height, cross-section bellow it can be seen that following Wednesday's cold front, the atmosphere will dry out for the remainder of the week. Along with the drying temperatures will climb before the next event this weekend. 

University of Utah Atmospheric Science

    If you plan to travel in the backcountry ensure you have the proper equipment and know before you go. For all things avalanche and the full avalanche forecast head over to the Utah Avalanche Center.