Wasatch Weather Weenies

One of the odder claims that I've seen in recent years is that March is Utah's snowiest month.  Ski Utah suggested this in their recent blog post March Always Delivers the Snow . Certainly March can be a great month for skiing, especially if you like the combination of a deep snowpack, longer days, and warmer sun, but is it really the snowiest? If one is talking about snowfall, that's debatable.  Below is the average total snowfall and average daily snowfall (in parentheses) by month at Alta based on data from the Western Region Climate Center.  Based on total snowfall, January is a bit ahead of March, although the difference is probably not statistically significant.  Based on average daily snowfall, a metric that I prefer because it adjusts for the number of days in each month, the snowiest months are January and February, although again, the difference relative to December and March is very small. November: 62.8" (2.09") December: 80" (2.58"...

After abandoning us for a stretch in February, it is clear that Meteorological Winter (the months of December, January, and February) is going to go out with a bang as snow impacts the morning commute across much of the Salt Lake Valley and the northern Wasatch Front today. The large-scale setup for this event is worth a peak as it features many of the characteristics that we often see when an upper-level trough swings across the Great Basin.  At 2000 UTC (1700 MST) yesterday, the system was "vertically stacked" along the Pacific Northwest coast with the 500-mb low center (as indicated by the 500-mb height contours in black) located nearly over the sea level pressure low (as indicated by color contours).  To the south, a pronounced lee trough existed downstream of the Sierra Nevada, from which a surface trough extended into western Utah. As the upper-level trough slid southward and eastward overnight, the Great Basin trough extended northeastward across northern Utah a...

A quick shout out to begin today's post to Mrs. Professor Powder, who celebrated her big five-oh in style today.  I must confess that I did pull the government weather-control lever to ensure bluebird skies and high-speed cruising for her birthday.   She has put up with my weather weenieness for just over half of those years and today was no exception.  So much to see!  Yes, the views were great, but did you spot the 22-degre halo? How about wind transport?  The photo below as taken about 1 PM.  At the time, winds on Mt. Baldy were a rather unimpressive 17 mph with gusts to 32.  No mind, there's plenty of low-density blower to transport and that speed will do it with snow like that.  We departed soon after, but I suspect that wind deposition rates increased further with the winds this afternoon.   With so much dry snow around, not just on the snowpack, but also in the trees, one could practically pick out the gusts by e...

As many of you are aware, the microclimate of the North Ogden Valley holds a special place in my heart (see Pound for Pound the Snowiest Place in Utah ). Source: Secrets of the Greatest Snow on Earth Every time I go there in the winter or spring, I'm blown away by the snowpack.  Today I needed to get some work done, and battling the weekend crowds in the Cottonwoods wasn't very inviting, so my son and I shot up to the Ogden Valley for some skinny skiing at the North Fork Park trail system maintained by Ogden Nordic . It's hard to believe that North Fork Park is at an elevation of about 5800 feet.  I check the map every time I visit there.  The snowpack is remarkably robust, blowing away anything at a comparable elevation on the back of the central Wasatch.  The scene today was a winter wonderland. I didn't measure snow depth anywhere, but the Ben Lomond Trail SNOTEL site is nearby and at an elevation 5820 ft.  For 24 February, the median snowp...

Ski touring this morning was the epitome of too much of a good thing, at least where we were.  New snow depths based on the highly scientific ski pole insertion were around a meter. Trail breaking, especially on the ridge we were ascending, was a pig wallow.  Special thanks to the two gorillas (you know who you are) who broke the first 2/3 or so ahead of us and eventually bailed off for a run.  Your efforts are appreciated! Options for turns were limited.  Diving into steep terrain invited the potential for powerful sloughing. Lower angle terrain required downhill trailbreaking.  Occasionally one could find a happy medium, but as soon as the slope angle backed off, you just augured in. Nevertheless, there were some visits to the white room. Those pictures look good, but I'll be honest, the skiing wasn't all that great.  Given the choice between a Goldilocks storm with good "bounce" or over-the-head blower, I'll take bounce every time...

We interrupt our regularly scheduled programming for deep-powder skiing and this message from Squaw Valley/Alpine Meadows , which is mind boggling and requires no embellishment.

A buried upper White Pine Canyon on December 24, 2010.  Snow depth at Alta-Collins: 105" While ski touring this weekend, one of my students had the audacity to ask me if this ski season is as good as 10/11. Now, in my mind, the 10/11 ski season is the gold standard since I arrived in Utah in 1995 for a variety of reasons.  First, the season started fast, with 62" of snow at Alta-Collins on 1 December.  Second, we crested 100 inches at Alta-Collins before Christmas, opening up adventuring in rocky, high-elevation terrain very early in the season (see above).  Third, there was abundant low-elevation snowpack, greatly improving access to many backcountry areas.  Fourth, the snow just kept coming and, although Alta ski area does not measure snow after the end of the season, a reasonable case could be made that they reached near 800 inches by the end of May (see Alta 800! ). Professor Powder getting Memorial Day Weekend 2011 freshies.  Photo: Tyler Cru...

Last night's storm delivered nicely across the central Wasatch with most upper-elevation sites reporting a foot or more. Although we're in a bit of a lull at present, the pattern setting up through Friday generally looks like a good one.  Today is a bit tricky, with the front sort of pinwheeling around and going through various phases of redevelopment, so I'm not sure how it's going to play out, but after that, we're in cold, moist, northwest flow for the rest of the workweek, such as advertised below by the NAM for 5 PM tomorrow (Thursday) afternoon. A quick look at the NCAR ensemble shows today's lull, but then the likelihood of precipitation increasing in the afternoon.  The waxing and waning of snowfall in the cold, unstable post-frontal environment is very difficult to time, but overall, I would expect we will see periods of snow showers through Friday (the graph below covers only through tomorrow afternoon, but other models support that view). M...

Here's an interesting non-alternative fact about our current wind storm.  Peak gusts over the past 24-hour period ending at around 8:30 AM are quite similar in the valleys and on the mountain ridges. Three sites have reported gusts in excess of 70 mph, two upper-elevation sites near Snowbasin (83 and 73 mph) and one in the western Uintas (77 mph) and these are the highest gusts so far in northern Utah.  So, technically one can find a couple of mountain sites that have the highest gusts in the region. However, if we move a bit closer to the Salt Lake Valley, we see that peak gusts in the valleys are comparable to those in the mountains.  Here's a selection from MesoWest: SR-201/I-80 Junction: 69 mph Park City Ridgeline: 69 mph Mount Baldy: 68 mph Stockton Bar: 68 mph Great Salt Lake Marina: 67 mph Mid-elevation Mt. Timpanogos: 66 mph Sandy: 66 mph So, what gives?  Why is the wind blowing so hard in the valleys, especially overnight? The peak gust in th...

Today featured strong south to southwest flow impinging on the central Wasatch, leading to the formation of a very pronounced cap cloud over Lone Peak and the Alpine Ridge separating Little Cottonwood and American Fork Canyons.  The cap cloud was illuminated in sunlight when I arrived home from my ski tour this afternoon. Cap clouds of the type above form due to orographically (i.e., terrain) forced ascent as flow impinges on the mountain barrier and is forced to rise.  It is very common to see such clouds over Lone Peak and the Alpine Ridge in southerly or southwesterly flow. This morning, the top of the cloud pattern featured a structure that looked liked breaking waves on a beach.  Such patterns are produced by Kelvin-Helmholtz instability (or K-H instability or just K-H for short).  K-H instability is named after Lord Kelvin and Hermann von Helmholtz, 19th century scientists who made important contributions to meteorology and many other scientific fie...

Today's ski tour was a bit like one you might experience in April.  Snow levels around 7000 feet (but higher overnight).  Wet sponge conditions in which you simultaneously get wet from the inside out and from the outside in.  Decent, creamy conditions above 9000 feet, but snow becoming increasingly cruddy and shallow with decreasing altitude below that point.  Then one returns home and it looks like April.  Warm and partly sunny with little low-elevation snowpack.   From a snowpack standpoint, this week was one in which the rich (high altitudes) get richer and the poor (low altitudes) get poorer.  In fact, traveling up and down Big Cottonwood Canyon today it was clear that this week was a total and complete disaster for the snowpack below about 8000 feet and especially below 7000 feet.  The snow losses below 7000 feet were visually staggering (I didn't take any photos) and where there was snow, it looked water logged and tired. I really w...

Yes, I know you are probably interested in the President's Day Weekend forecast, but you can get that elsewhere.  We try to look at things differently here at the Wasatch Weather Weenies.  Thus, we're going to Mexico, with a return trip to California and Utah. Why?  An exceptionally deep upper-level trough will be impacting northwest Mexico Friday and Saturday as part of the storm system that is also sweeping across the western United States.  The GFS forecast loop below shows the band of heavy precipitation sweeping through the Mexican states of Baja California, Baja California Sur, Sonora, and Sinaloa with the 500-mb trough. That 500-mb trough is exceptionally deep for such a low latitude.  As it sweeps over Cabo San Lucas, the 500-mb heights are lower than anything observed during this 3-week period in the Climate Forecast System Reanalysis record for 1979-2009.  Basically, the jet stream has decided its had enough of the cold mid latitudes and is...

California is a land of weather extremes.  Most of the California's precipitation falls from December through March, during the so-called "wet-season."  However, the precipitation that falls each wet season varies greatly, leading to precipitation extremes that include seasonal or multi-year droughts and pluvials (periods of increased rainfall). I hesitate to use the word "cycles" to describe the fluctuations between these precipitation extremes because they are not regular.  Instead, it is probably best to say that the precipitation climate of California is highly variable. Only last year California was mired in extreme drought.  That has certainly changed this year with heavy precipitation and remarkable mountain snowpack.  However, as impressive as this past winter has been so far, the potential exists for even greater precipitation.  Geologic evidence suggests that massive flooding strikes California every 100-200 years (some studies suggest a longer ...

Thanks to world travels, inversions and air pollution, and active storm cycles, I haven't had a chance to throw some climate tidbits at you in some time.  Here goes. 2016 Warmest Calendar Year on Record Globally I'm late to the party on this one and you probably knew this already, but 2016 was the warmest calendar year on record, inching out 2015.  Collectively, those two years easily represent a new "high" for the planet, well above anything else in the instrumented record. Source: National Centers for Environmental Information Tough to say if 2017 will set another record.  I wouldn't be surprised if we pushed it a bit higher, or if we settled back a bit as has often happened during the long-term warming trend over the past few decades.  If the latter occurs, don't fall talk of a global warming pause or hiatus.  The train has left the station and we're on our way to a warmer future. No Record for Utah The statewide average temperature in 2016 ...