An Oasis or a Mirage?

The Cottonwood resorts were able to squeeze all of 1 inch out of the very weak disturbance last night and cloudy skies have been the rule today.  Matt L was thinking that there might have been more, but alas, it was only enough to produce some wisps as you cruised down the groomers.  A shearing, negatively tilted trough will come onshore in California tonight, adding more to their much-needed totals. 

The trough really falls apart tomorrow though, and the moisture and lift just aren’t going to come together for Northern Utah.  I think an inch or less is a good bet Wednesday.  Like Matt L mentioned, Brian Head might be able to get to 6 inches or so as they will have more moisture to play with.  The shreds of the trough will hang around Thursday, bringing grey skies and maybe another inch to the Wasatch.  Beaver Mountain and the Logan-area mountain will do better Thursday, with 1-4 possible by Friday morning.  

Looking forward from Friday, the large scale pattern will begin to shift from what we have seen this week.  According to the current GFS, the polar jet over the eastern Pacific will become fairly static as a deep long-wave trough sets up over the Central Pacific.  Such a pattern will keep the proverbial firehose pointed right at Oregon and Washington.  Enough of this moisture will make it inland that Northern Utah could do pretty well in the moist WNW flow from Sunday to next Tuesday, albeit with high freezing levels. The ECMWF ensemble likes it too, with virtually all the ensemble members on board with the idea of a strong, wet westerly jet hitting the northwest US. 

The only question is whether we will end up too far south to get it!  This setup lookssimilar to the one that really gave our season a kick in the pants last February, where the Cottonwoods did well, low elevations got rain, and areas from Logan, UT to the Tetons just got hammered. 

In short, don’t bank on it yet, but the 5-7 day outlook is hopeful.

Dense powder is still powder

As anticipated, the first part of this storm came in like concrete; shallow clouds and warm temps are a recipe for dense snow. We are now entering into the cold phase of this storm, so the snow that falls tonight and tomorrow should finish us off with a nice right-side-up snowfall.

 

Before I get into the forecast though, here’s a look at how snowfall totals are coming along throughout the Wasatch for this storm:

Alta Collins and Top Cecret: 4″

Snowbird: 5″

Thaynes Canyon Snotel (PC resort): 2″

Snowbasin: 7″

Ben Lomond Peak Snotel: over 10″

Tony Grove Lake Snotel: 3″

 

All of these locations came in at over 10% water content, so like I said, quite dense, but the skiing on the 5″ at Snowbird today was surprisingly good! Creamy powder is still powder, and it is also very good at covering up rocks and building a base. On a final note, you can’t ignore that huge number on Ben Lomond! It appears that during the pre-frontal W/SW flow, orographic precip generation went big up there. I say over 10″ only because there is no board to sweep at snotel sites, and settlement of the snow makes it impossible to say just how much fell. Needless to say though, they’ll likely be the winners for this storm.

 

Now for the forecast, I’m gonna stick with the storm total numbers that others before me have put up. We’re just shy of verifying within our ranges, so the additional snow that it appears will fall should push us into those ranges. Periods of snow will continue through tomorrow (Sunday), with things winding down in the afternoon/evening. One wild card with the cold upper-level temperatures though, is lake-effect, and there is a chance we could see a band Sunday. This would give us a few more inches in the Cottonwoods than forecast if were to happen.

 

Long range still looks similar to what Trey described, with a shot at a fairly weak storm in the Tuesday-Wednesday timeframe. In the mean time, get out and enjoy the snow!

Snow. Finally!

As I write this early Friday evening, precipitation can be seen moving into radar range..when was the last time we could say that?! As I’m sure many of you have noticed, it’s been unseasonably warm. Today we broke another record high at Salt Lake Int’l Airport. Why’s this important? It means any pre-frontal precipitation will fall as snow only at very high elevations. The bulk of precipitation is expected to be associated with the frontal passage, however, so snow levels will lower during the heaviest precipitation. A few quick model numbers for the Nrn Wasatch: GFS = .2″ qpf, ECMWF = .5″ qpf, NAM = .4″ qpf, GFS (4 km) = .6″ qpf,  NAM (4km) = .8″ qpf. If we grossly used a 10:1 snow ratio that would yield about 2-10 inches for the model solutions. So what are we calling for?

 

Like Ian said in his forecast below, we’ll likely see modest accumulations with the front overnight tonight followed by additional accumulations Saturday PM. Overall, I’m sticking with the 6-12 inches for the Upper Cottonwoods as we’ve called for the last several days. Lower totals in lower elevation areas like PC: 3-7 inches (higher amnts possible above mid-mountain). This storm will be “right side up” so it at least has that going for us. Groomers will probably be great, but off trail you’ll risk hitting crust or hidden rocks. 

 

Long range

Another storm is on tap for mid-week! Unfortunately, it looks like the bulk will miss us once again, but any snow is welcomed. And it could still be decent: ECMWF gives us solid accumulations, GFS and ensembles not so much. We’ll hopefully have a better idea once we get this storm out of the picture.

 

 

 

Rummaging for Scraps

One of the most impressive storm systems in years is already making its impact felt along the Pacific Coast.  The National Weather Service has issued just about every kind of warning it can issue, from high surf and wind to blizzards.  Places in Washington State have already totaled up 10 inches of water.  Too bad it was just that- water.  At that particular station what snow was present has now been washed away.  And that is only 1000 feet below treeline!  Not great for skiing, although the storm will finish with lower snow levels.  

As the previous post mentioned, it would be great if the Sierra Nevada didn’t exist right now.  They will doing their best to remove moisture from the air these next few days.  That’s fine. California needs it much more than we do.  Utah is most likely to get snow between Friday evening and Sunday morning as the Pacific trough passes over us.  The biggest variable in my mind for snow amounts is how long the moist northwesterly flow behind the trough lasts.  It is during this post-trough NW flow that the Cottonwood Canyons can really get it. Looking at the GFS and EC I think something around 7-14 inches is possible in the upper Cottonwoods, with 4-9 elsewhere.  That 14 is a little bit on a limb, but I think the potential is there due to the cool, moist NW flow. The storm should be all snow at the resorts, with the bottom of Snowbasin and Sundance being the only possible exceptions Friday night.  

Right now it looks to me like Saturday will be the better day to ski, but I say that with low confidence.  Never turn your back on a model indicating moist northwest flow.

The long range doesn’t look great with split flow dominating.  

Relief is on the way!

Jeff and I went for a tour along the Park City ridgeline today, and it felt like a March day. The south aspects were getting slushy (even up high), and it was very much a short-sleeve affair while climbing. Despite the toasty temps though, it is December and the sun angle is very low, so the high elevation slopes facing more toward the north still had great snow! Surprisingly great snow. This warm spell (December heat wave?) will persist for a few more days unfortunately. In fact, tomorrow through Thursday will be even warmer than today. Thursday will likely be the toastiest day this week…getting about as warm as it can get in December. Skies will definitely be bluebird on Monday, and for Tues-Thurs, there should be a reasonable amount of sun, although some weak disturbances passing to our north may bring some periods of clouds. Now for the good stuff..relief from our snow drought is in sight!

I think we’ve gotten to the point (as far as model predictability goes) where I can say with reasonable certainty that we will be getting a storm late week/this coming weekend. The devil is in the details though, and here is what remains uncertain where we stand now, 5-6 days out:

-Timing: the ECMWF has the show starting much later and ending earlier than the GFS. This affects snowfall totals greatly; you need a long duration storm for lots of snow.

-Where the best large-scale rising motion will be: if it doesn’t set up over Utah, we won’t get very much snow.

-Which direction the upper-level winds will be coming from: the preferred corridor for moisture transport into Utah is through NorCal/S. Oregon…I’m a bit worried with our moisture tap coming from the southwest. The model solutions will shift around in the coming days, and if things move north (over the High Sierra Nevada), we could miss out on the Grade A pacific moisture.

-Temperatures: right now the temperature trend during the storm looks great (starting warm, ending cold), but the model soutions will shift around as I mentioned, so we’ll keep an eye on this.

So all we can say is that a storm is very likely; we’ll let you know as soon as the details and strength of this storm come into focus.

Same ole Same ole

It looks like we’ll continue with warm and dry conditions through mid-week, unfortunately (although this is perfect biking weather…gotta find some good with the bad). The models are continuing to depict a strong trough impacting our area late next week, but run to run consistency has been lacking. Significant timing and amplitude differences exist between the GFS, EURO, and ensembles, however, at least all the models are showing some kind of trough by next weekend. As good as things were a couple weeks ago, this latest drought (As Matt mentioned) has now pulled us behind in snowfall totals :(. It’s still VERY early in the season, though, so things can change. In the meantime, enjoy this pleasant weather and shred some groomers!

 

Warm and Dry

Well, the prognosis is still not good for snow in Utah over the next 5 days.  Some flurries are possible Saturday, and thats about it.  The one silver lining to all the warm weather and clouds has been that weak layers in the backcountry are healing.  Other than that, though, I can’t think of much good that is coming from this pattern.  

It doesn’t really feel like it, but we are only slightly behind average for snow in the higher elevations of the Wasatch right now.  Most stations are 75-90% of their normal snowpack water content.  Up by Logan they are above average.  If you want a deep snowpack you can drive to Jackson though. They have been doing fairly well the last couple weeks, with 50% more season snowfall than the Cottonwoods.

In long range model dreamland there is a good, wet trough making its way into Utah on Thursday next week in the deterministic 12Z GFS.  Who knows if it will happen.  We can hope..

Covering up a few of those rocks

We’ve got another storm coming in starting Wednesday morning! Woooo more snow! Now that I got that out of the way, I’ll add that it’s going to be (yet another) warm and weak storm. Oh well, I’ll take it. The steeps at Snowbird were still pretty rocky this weekend, so the dense snow that will fall should be pretty helpful. For those (like USW’s Matt Jeglum) who were lucky enough to be out touring in the backcountry, the coverage was adequate on the less-rocky terrain and the snow skied well, but avalanche conditions remain quite spooky. Be careful out there.

The storm coming our way is a closed off low-pressure system that has been spinning off the coast of California for the past few days. The low is finally getting picked back up into the storm track, but unfortunately it will be filling (weakening) hastily. This means that although we have a decent amount of moisture that has been pumped into the interior West, the amount of rising motion in the atmosphere to generate precipitation will be fairly limited. The window of time we have to generate snow over the mountains varies between the GFS and ECMWF models, but I’m thinking Wednesday morning through Thursday morning is reasonable, although snowfall rates will likely be pretty low and the rain-snow line will be fairly high due to warm temperatures. With that in mind I’m gonna go 4-8″ storm total for the high elevations of the Cottonwoods, Timpanogos area, and the northern Wasatch, with 2-4″ in the Park City area. The rain-snow line may be near the base of Snowbird and Solitude at times, and unfortunately the PC resort bases will likely see some rain.

UPDATE @ 10am Tuesday: I just don’t like our chances for 8″ of snow anywhere in the Wasatch, so I’d count more on 3-6″…this storm has continued to undwerwhelm me in the models

Long Range:The long range is all over the place. This afternoon’s run of the GFS model just magically created a storm this Saturday over Utah. The ensemble members say it should be a weak storm at best. I’m not gonna bite yet, so I’ll say we have a shot at a weak storm this weekend. That’s it…hopefully Jeff will have more for you tomorrow.

The North wins again

It seems to be a reoccurring theme from last season, the Nrn resorts and mountains faired much better with today’s frontal band than areas near and south of Salt Lake City. Overall, it looks like 4-8 inches of snow fell between Pow Mow and the Beaver with only an inch or 2 for all other areas. Snow showers will continue in the Wasatch tonight but highest amnts will remain in the far north. 

 

Looking Ahead: Unfortunately, the trend is not our friend. I hate to be the bearer of bad news, but the models have continued to depict a weaker, less amplified trough for mid-week. So in response to Matt’s question in the previous blog, it doesn’t look like we’ll be getting very wet. The atmospheric river won’t penetrate very far inland; so this along with a weaker trough means marginal snowfall accumulations. Right now I’m thinking ~ 3-6 inches through Thursday. I’ll definitely be happy if we can squeeze 6 inches out of the mid-week storm, all things considered. In the longer range it doesn’t look like anything significant at least through next weekend.

California is gonna get wet. Will we?

Lets get the weekend forecast out of the way so we can talk about the next potential big storm.  

A fairly strong cold front dropping south from Canada will push just about to the Utah-Idaho border by late Saturday.  This will bring mind-numbing temperatures back to Montana and a decent shot of snow to the Bear River Range near Logan and maybe the Northern Wasatch on Sunday.  Right now I would say we are looking at around half an inch of water for the mountains east of Logan decreasing to maybe and maybe half that by the time you get as far south as the Cottonwoods. With relatively moderate temps this will probably translate to 4-8 inches of snow near Beaver Mountain and a measly 2-5 in the Cottonwoods and Park City.  Snowbasin and PowMow will be in the middle. 

On a side note, The Bear River Range is picking up where it left off last year in terms of just getting dumped on. After leaving the Central Wasatch in the dust during the latter half of the ’13/’14 season, the Tony Grove SNOTEL in the Bear Rivers is at 163% of average snowpack for the date.  There is 40% more snow-water on the ground there than at Snowbird.  

Hopefully the Cottonwoods and points south will hopefully be able to make up some ground next week.  The EC and GFS models have been consistent on a closed-low pressure system slowly drifting off the Pacific into California on Monday and Tuesday.  This low wil be associated with a moisture plume coming out of the sub-tropics called an atmospheric river.  With this juicy subtropical air slamming into the Sierra Nevada, California stands to get a good soaking.  Where the models haven’t been consistent is whether this moisture may make it inland and if so, where it would fall.  The current GFS and EC solutions have it wet in the Wasatch Tuesday-Thursday, but looking at the ensembles still shows that things are quite uncertain.  I won’t bother with any specific snow forecasts yet, but the potential is there for a foot-plus if things come together.  Its been a while since we had a good base-building southerly flow storm so I am crossing my fingers we get it.

Matt