It is worth a look at the intricacies of our current inversion event in which the inversion has lifted some, which brings with it some good news for valley residents and some bad news for bench residents.
Note how in the morning sounding below, temperatures decrease from about 0ºC at the surface to -5.3˚C at 6400 ft (810 mb) where the inversion is based.
Source: SPC
As a result, instead of pollutants being trapped in a very shallow layer close to the valley floor, they are actually mixing through a depth of about 2000 feet. This means lower pollution concentrations on the valley floor. Note, for example, how much lower PM2.5 concentrations are today compared to the previous day at Hawthorne Elementary (it's possible there was some flushing in of cleaner air in easterly flow too, but I suspect the raising of the inversion was also a contributor)
Source: DAQ
On the other hand, the deeper pollution layer means higher pollutant levels on the upper benches (compared to shallower events) and in some areas such as the lower canyons. The photo below, taken looking north from upper Mill Creek Canyon, shows low clouds tonguing up Parleys Canyon, and with it air pollution. Skate skiers at Mountain Dell, for example, are probably seeing moderate air quality levels this afternoon. That might also be true in lower Mill Creek Canyon.
The Snowbird Prism Cam also shows the sea of stratus over the Salt Lake Valley, with a tongue pushing up Little Cottonwood.
I suspect the development of down valley flow tonight will cause a flushing of clean air into the lower canyons, which will be followed by a push of dirty air and stratus up the lower canyons tomorrow, as occurred today.
This is a repost from 11 January 2013 just because it is fun to reminisce.
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The U closed today at 1 PM and we took full advantage by taking a tour in the Avenues Foothills. There's an impressive snowpack at the top of Terrace Hills Drive (~5000 ft).
Good cover on the mountain bike trails.
We made a brief visit to the white room. Yes folks, this was in the Avenues foothills.
The snowpack on the north aspect is quite scary. Facets down low (very soft) and column failures with isolation at the old snow/new snow interface. We kept slope angles low, which made it a bit challenging to keep momentum going given the depth of the new snow. Better safe than sorry.
In all honesty, the snow is too deep and too dry for good skiing. I think the skiing will be better once things settle out some. When's the last time you said that about skiing from town?
Pretty interesting snowpack numbers across the western U.S. so far this season. Most basins currently sit near or below median snowpack water equivalent for this time of year, although there are a few draped across the central mountain west that are at or above average.
Stations in the southern, central, and northern Wasatch sit at 83% (Cascade Mountain) to 130% (Hardscrabble) of median.
I prefer to use median rather than average for these comparisons since it lies at the midpoint of the historical record. A small number of big snow years tend to yield an average that is higher than median.
Data from snowbird shows we have been pretty close to median for most of the cool season.
That's a nice start, especially compared to recent winters, but we still have a long ways to go. Nobody really knows how the rest of the season is going to go in northern Utah (at least nobody who can claim to be able to produce a reliable forecast). The Climate Prediction Center gives us "equal chances" for precipitation over the next month, which basically means we have equal chances for below, near, or above average precipitation.
I'll call the snowpack so far both half full and half empty. Half full because it has been a decent ski season. Half empty because we still have a long ways to go.
I left town on Saturday morning to attend the annual meeting of the American Meteorological Society in Phoenix. Like clockwork, it has been snowing and snowing big. Alta-Collins recorded 16 inches Saturday night and Sunday and then another 3 inches last night (through 8 am). After today, things look to settle down for a few days, at least if the SREF forecasts hold.
I've also been drooling at the snowfall amounts being recorded in the northeastern Alps of Austria.
With my Fulbright starting in Innsbruck in a couple of weeks, I have been thinking a bit about my first trip to Austria in 2001.
For that trip, the Salt Lake City Organizing Committee for the Olympic Winter Games (SLOC) asked me to go to the 2001 Alpine World Championships in St. Anton to observe logistics for the event, including weather. I had already done this at the 1998 Nagano Winter Olympics, so I initially begged off, but they were persistent. After reading a quote about St. Anton being one of the best ski expert ski areas in Europe with a hedonistic nightlife, I figured I would go.
The trip started out on a low note as I injured my knee skiing the day prior to our departure and could barely walk on the plane or the first couple of days we were in Zurich meeting with MeteoSwiss (the Swiss National Weather Service). Our first day in St. Anton, which was bluebird with deep powder, did not have any official activities planned. I ended up working and meeting with the meteorological support team for the world championships while the others skied.
Subsequent days I was feeling better and got up on the courses and learned about the logistics and weather impacts. This was a "tough assignment" involving skiing, watching races, and having a former U.S. ski team coach give you a colorful play-by-play of the events as they unfold.
On the morning of the Men's Super-G, we had pretty much learned all we could and decided to get up early and check out Lech, one of the ski areas in the Arlberg. We got on the lift with an Austrian Ski Instructor who asked us who the big American was. We said, "Daron Rahlves". He replied, "Never heard of him."
The skiing was terrible. It was foggy and the snow was subpar. We decided we should go back and check out the Super-G, which turned out to be a great decision. When Rahlves left the start house, Austrians were in first (Stephan Eberharter) and second (Hermann Maier) and positioned for a huge win on home snow.
Rahlves crossed the finish line with the best time by 8 one-hundredths of a second, resulting in two Americans jumping up and down and screaming "Never Heard of Him." It's worth a look at the Eurosport coverage of the race.
It was a great win, but Jingoism aside, I've always admired the Austrian ski team and the many great skiers that they've produced. The powerful Herman Maier was a huge favorite of mine. Pick up a copy of his book The Race of My Life, which chronicles his comeback from a 2001 motorcycle accident, if you can find it reasonably priced somewhere online. Although we will not attend in person, I'm very much looking forward to watching the Hahnenkamm downhill in Austria. If you are wondering, the last non European to win it was Daron Rahlves on a shortened course in 2003. Rahlves is still getting after it.
The new year is here and my sabbatical begins officially on January 7th. I'm pretty excited as I will be serving as the Fulbright Visiting Professor of Natural Sciences at the University of Innsbruck beginning on March 1st. The appointment will involve teaching classes in atmospheric and related sciences, as well as forging research ties with their Institute of Atmospheric and Cryospheric Sciences.
We depart in about two weeks and will be living in Innsbruck for about 6 months. We have run most of the gauntlet needed to move temporarily to Austria, but still have a few issues to take care of. Perhaps most challenging was getting a packing system down that will allow us to get all of our gear to Innsbruck in two checked bags and a carry on. Sadly, I need to leave my skate gear at home, but may rent for a couple of days to try out the 2019 Nordic World Championship track in Seefeld, just outside of Innsbruck.
I've been watching the Innsbruck area web cams and ski reports for a few weeks and have been getting nervous as the snowfall has seemed fair at best so far and non-existent in the lower elevations. However, a storm has finally descended on the area and there's some white now even in town.
The forecasts are looking optimistic. I haven't dialed in my software yet for the Alps, but the GFS loop below shows a prolonged period of moist northerly flow impinging on the eastern Alps over the next few days.
Water equivalents produced over the next five days by the relatively low resolution GFS exceed 10 cm (4 inches) in some areas, so this should be a game changer for the Austrian ski season.
You may be wondering what will happen to the Wasatch Weather Weenies while I am gone. My plans are not certain, but I am anticipating doing occasional posts on Austrian skiing, culture, and weather.
