Mediocre or bad? That is the question

Well, here’s the deal.  We have a couple sad excuses for troughs moving through Utah between Sunday and Tuesday.  The heat, sun and wind have taken their toll on the snow and conditions are about as bad as Utah gets this time of year.  Whether you believe the GFS or Euro model depends on whether we will get an upgrade to mediocre conditions by Tuesday or we will simply stay at bad.  But we can’t complain too much, we could live on the East Coast. 

The GFS is currently really dry over the Wasatch, with only 2-4 inches forecast by Tuesday.  If the juiciest band in the GFS shifts over the Wasatch, make that 3-6. Southern Utah will do better.

The EC ensemble is looking a little better with more like 3-6 possible by Tuesday, with the most optimistic members maybe getting to 10 inches.  I know, its depressing.  Overall the expectations are down a little from what Matt forecasted yesterday. The forcing for precipitation in these troughs will be more dynamic than orographic, so there may not be huge biases from one resort to another.  Due to uncertainty with what will happen, I am not even going to bother with resort specific amounts except to say that whatever falls definitely won’t come before Sunday morning.  Sunday could be a real bad day if clouds keep the sun at bay and all the ice just stays ice without much new snow falling.  During the day Monday looks the most likely to see snow. 

The long term still looks depressing with another big ridge next week.

The Heat is On

With the partial mix-out of the valley cold pools yesterday, loss of some snow cover, and an exceptionally warm upper-level airmass working into Utah, we have actually managed some pretty warm temperatures in the valley for a January inversion episode. The WBB weather station at the U currently sits at 51 degrees…pretty impressive. Unfortunately, this means that the heat is also on in the mountains. Alta-Collins is at 37 F, and the bases of the PC resorts are in the mid 40s.

As promised, a strong upper-level ridge has been building over the intermountain West, and it will continue to strengthen its grip on us through tomorrow. Today has been very warm, but tomorrow will be pretty exceptional. As Trey mentioned, the 700mb temperature will likely exceed 6 C…this is just about as warm as it can possibly get in the Wasatch in January, As a result, we’ll likely see mid to upper 40s at most resorts, and the south-facing slopes are going to get cooked. Wet-loose avalanches are also going to be running on these aspects. One bright spot to this heat wave is that it is early January, and the sun angle is low enough that the snow on high-elevation north-facing slopes may remain relatively intact if we remain cloud-free and the humidity is low enough.

Thankfully, the ridge starts to flatten after Wedsnesday, bringing a slow cooldown through the weekend. The EC and GFS are also bringing a storm through Utah early next week, but there is some uncertainty as to the quality of the storm. At this point though, a cooldown and fresh snow are more than enough to make me happy.

 

If you want Powder go north

Unfortunately the Wasatch missed out on some big-time snow by just a few hundred miles. If you want some fresh snow go up towards Jackson Hole and points north into Montana..they’ve gotten hammered the past couple days! Meanwhile, we haven’t seen much down here in Utah and things don’t look like they’re in a hurry to change any time soon. 

Strong ridging will move overhead mid-week with warm spring-like conditions in the mountains and strong inversions in valley locations. 700 mb temperatures will reach 6 degrees Celsius by Wednesday which is very warm for this time of year. Resorts will probably top out in the mid-upper 40s!!  Things begin to cool down a little by the end of the week as the ridge axis moves away, but it still remains entrenched enough to void the area of any significant storms. A couple weak systems may impact parts of Utah this weekened into early next week but I don’t see anything of any significance for the next 7 days.

Bring a beach chair

Unfortunately the most significant news I have to rely from the forecast for this next week is extreme warmth.  Wednesday in particular will be an awesome day to get a head start on your spring break tan up at the resorts with temperatures in the 40’s.  The valley air will grow dingier and dingier as well.  This is a classic inversion pattern, with a big ridge building over the West.  Thankfully the low sun angles will preserve the snow on the high north faces, but icy or slushy snow will be widespread elsewhere this upcoming week.

Sunday and Monday we will get brushed by the strong NW flow that will deliver quite a bit of snow to the Jackson area.  So head there if you want to ski powder this week.  In the central Wasatch this system will amount to just some flurries and clouds.  Beaver and other areas north have a chance of recording an inch or two. 

In the long range, the GFS has been hinting at a trough for next weekend, but the details are never consistent from run-to-run so confidence is low.

Thawing Out

Last night and today were a great example of a process in the atmosphere that we meteorologists refer to as “advection.” When the sun set yesterday evening, the temperature quickly plunged to -2 Fahrenheit at the Alta-Collins obsevring site. Instead of dropping further, however, the temperature actually rose throughout the night, reaching a balmy +7 Fahrenheit by 7am. This was the result of warm air being transported by the upper level winds into Utah. Pretty amazing to have the temperature increase on a clear december night, and an example of one of the many challenges in weather forecasting…the temperature doesn’t necessarily drop overnight!

Anyway, what does this mean for your weather forecast in the Wasatch? Well, the cold air we have sitting in the snow covered valleys isn’t going anywhere, so the warming air overhead means that inversions will set up in the valleys, with temps warming in the mountains through Friday under partly-mostly sunny skies. This should make for great skiing weather!

I know I know, most of you want the snow to come back though. So do I, but the outlook is not terribly encouraging. I think we’ll see some light snow (and a brief return of colder temeratures) on Saturday as a shortwave trough over Wyoming passes by us, but as Trey mentioned, doesn’t look like much of an event for the Wasatch. And it will be short-lived.

Long Term: After Saturday, things look to get quite warm in the mountains unfortunately. Not great for the snow on south facing slopes, and not great for air quality and temperatures in the valleys, which will be cold under stout inversions. All model guidance points to a pretty strong ridge sitting over us through at least mid-week, BUT I do see reason to hope for the late-week timeframe…until then, enjoy the sunshine. We were pretty spoiled by this last storm cycle, and you’ve gotta have a break here and there. Get your work done around the house so you can be ready for the next one.

Have a safe and happy New Year!

A Break in the Action

Unfortunately, the active storm pattern we’ve seen the last couple weeks has come to an end. It’s been a remarkable run with the snowpack doubling in just the past 2 weeks! The storm cycle stacked up perfectly beginning with a dense Atmospheric River event followed by progressively less dense snow, and ending with an incredible 4% in the final burst. Hope everyone was able to get out and enjoy it! I’ve been out of town and my arrival has brought an end to the active storm cycle (don’t worry, though, I’ll be gone again in 10 days and with that I’m sure things will get active again 😉 ).

A quick rundown of what to expect for the next week: Temperatures in the mountains will progressively warm to near climatology norms by the end of the week. This warming will occur as strong upper level ridging moves overhead. And you all know what that means for the valleys this time of year especially with a snowpack: Inversions! We could get a little something from a shortwave trough this weekend but the models currently keep it north of the Wasatch (though the ECMWF is slightly more amplified/farther south). At the very least hopefully this will help mix out valley inversions some. We’ll continue to keep an eye on this feature but it doesn’t look to be of anything significant attm. Beyond the weekend it doesn’t look like anything noteworthy until maybe mid-week at the earliest.

Wow!

Well, the totals so far include 20 inches of 4% blower at Alta, with 8 inches of that falling overnight.  Conditions yesterday were awesome, and figure to be all time today if you can get to places that didn’t get skied yesterday.  The Upper Cottonwoods, not surprisingly, did the best, and have exceeded our foreast totals.  Other areas got around 6″. The trough producing this precipitation will continue to elongate in an east-west orientation.  This elongation will keep weak synoptic lift going over Utah and as a result snow showers should continue through Tueday afternoon, favoring the southern half of the Wasatch.  Air temperatures look to remain bitter cold during that time as well.

I expect that areas north of I-80 will only get 1-4 more inches from these remaining showers through Tuesday, while areas south will see more like 2-5.  And of course 3-7 inches for the Cottonwoods.

From Wedenesday forward the trough elongates enough to cut off, leaving a weak low pressure system spinning over Southern Utah.  This system may produce some snow over the Arizona border.  Otherwise, things actually look fairly dry over Utah over the next week with ridging over us.

Storm Update

UPDATE @11:30am 12/26: Looks like we have now solidly nailed the forecast for all of the areas.

With Deer Valley at 9″ storm total and Canyons at 12″, the Park City resorts are within our 6-12″ range. We went for 12-24″ for the Cottonwoods resorts, and Snowbird and Alta-Collins sit at 18″ and 19″, respectively. Powder Mountain and Tony Grove Lake picked up 13″ and 9″ respectively, with our forecast of 8-16″ for the northern Wasatch.

Big kudos to Matt Jeglum for nailing this storm from 3 days out with his Deceber 22nd forecast!

 

Snowy Gifts

The much-anticipated Christmas storm blew into Utah in the wee hours of Christmas morning and delivered a nice little blanket of low-density powder to both the valleys and the mountains. I heard the skiing in the Cottonwoods was great today. Although the upper-level trough continues to spin over us, snowfall has tapered to flurries for the time being, so let’s take a look at snowfall totals so far:

Snowbird: 14″

Alta: 12″

Tony Grove Lake (Northern Wasatch): 8″

Ben Lomond (Ogden area mountains): 7″

Canyons: ~8″

If you looked at our forecastsfor this event, you’ll notice that our prediction of 12-24 for the Upper Cottonwoods has verified, albeit just barely! It appears we are good for the Northern Wasatch and PC side too. The northerly flow present during much of this event after the cold front passed was really not ideal for orographic snowfall enhancement in the Wasatch…this cut the totals down. So the question then becomes: can we squeze out a few more inches before the upper-level trough leaves us late tomorrow???

Well the computer models this evening are already wrong right out of the gate…according to them the snow should still be falling at moderate intensity. And as I said earlier, there’s not much more than flurries falling right now. So, I’m gonna have to do some old school forecasting tonight…this northerly flow direcation has been relatively unproductive this evening, but I wouldn’t be surprised if another small scale feature in the trough provides enough lift to drop a few more inches. So I’m gonna go 2-5″ more for the upper Cottonwoods and 1-4″ more elsewhere.

The next storm comes our way early Sunday as another cold trough drops out of the Pac NW. The good news is that it should bring more of the light, fluffy powder we saw today, but the bad news is that I don’t forsee this being a very big storm. We’ll give you some snowfall numbers tomorrow.

The long range after this does not look overly promising, although I think the model solutions may flip for this time period, so don’t write it off completely.

 

I’m Dreaming of a White, Blower Pow 5% Density Christmas

The 7 day period stretching from last Friday to this Friday may go down as one of the best for the Cottonwoods in quite some time (at least since last season…). We’ve already gotten the “dirty” work out of the way with this past storm putting down extraordinarily high amounts of snow water or SWE (> 5 inches in the Upper Cottonwoods) cutting what was a 40% deficit into a surplus!!! The news gets better, though, and for Christmas day things are looking downright scrumptious.

A MUCH COLDER trough (than the previous system) will bring a strong cold front in from the NW with most of the precipitation falling during and after the frontal passage. Winter will finally truly arrive for all of Nrn Utah early on Christmas morning with snow levels crashing down to valley floors, which has prompted the issuance of Winter Storm Watches. The Cottonwoods will likely fair the best once again since at least a portion of the post-frontal period will see NW flow. Here are some of the model snow water or QPF totals: GFS = .6″ NAM = .8″ ECMWF = .8″ 4km NAM = > 1.15″

Like I already mentioned this storm will be COLD with densities around 5%, our first true blower powder of the season. Snow will intially be higher density but the switch will be very quick as the trough ushers in much colder air aloft. Thus .6″ of QPF would yield appx. 12 inches of snow. With all of this said I’ll stick with Matt’s numbers from yesterday:

12 – 24 inches in the Upper Cottonwoods 

8 – 16 inches in the Northern Wasatch

6 – 12 inches in Park City

Small caveat: As is often the case with COLD NW flow storms, there will be the potential for a lake effect band to form. Uncertainties in the flow direction precludes a more confident forecast, so I’m sticking with the same #s for the Cottonwoods. Just keep in mind that totals there could easily end up in the upper range or even higher if a lake band forms and parks itself over the Cottonwoods. Hopefully we’ll have some better ideas on this potential tomorrow.