Wasatch Weather Weenies

Last night's storm was a bit of a bust, putting down only 5" at Alta-Collins, so we turn our attention to other weather matters, namely the lake-effect rain falling in the western Salt Lake and eastern Tooele Valley this morning. Satellite and radar imagery show a nice wind-parallel cloud and somewhat disorganized precipitation band south of the Great Salt Lake. Fortunately for commuters, this is a relatively warm event and the precipitation on the valley floor is falling in the form of rain.  Here's a webcam image from Lakepoint near the northern tip of the Oquirrh Mountains. This is a somewhat unusual event in two regards.  First, the difference between the lake temperature (+6ºC) and the temperature at 700 mb (-7ºC) is pretty small (13ºC).  For many years, meteorologists assumed that temperature difference needed to be at least 16ºC for lake-effect to develop, but in recent work, we show that lake-effect can occur at values as low as 12ºC ( Alcott et al. 20...

Today's post goes out to Harold Ramis, who passed away in late February.  Ramis wrote or acted in many of the great comedies of my youth including Meatballs, Animal House, Caddyshack, Stripes, and Ghost Busters.  If I'm killing time flicking channels and find one of these movies, I'm hooked until they are over and my kids roll their eyes as I recite every line by memory.  Dean Wormer's lecture to the guys from Delta House is one of my favorites, and I enjoy it even more now that I've been a professor and a Department Chair. I thought of Ramis because he wrote Groundhog Day, the movie in which Bill Murray's character is a weatherman who experiences the same day over and over again.  On the large scale, the system we have rumbling into Utah is a bit of a repeat of the previous one in that the upper-level trough and attendant cold front are rolling over and through a long-wave ridge.   On the other hand, the system is stronger and, although it is curre...

 We are entering the home stretch of the 2014 Utah Legislative Session.  A number of bills related to air quality are under consideration, either in committee or in the House or Senate.  If you are interested, the best summary I can find is at the Healthy Environment Alliance of Utah (HEAL) web site. Whether it be at the national or state level, it's quite a gamut that a bill must run to become a law.  One congressman's chief of staff told me several years ago that only 3% of the bills proposed in Congress eventually become law, and most of those that pass are for trivial things like declaring broccoli the vegetable of the month.  I'm not sure if that 3% number is accurate (it might be high, especially in the current Congress), but his point was simply to illustrate, as is also done in the great Schoolhouse Rock video above, that it is very difficult to pass legislation. Air Quality related bills still in play this legislative session include one to ph...

Let's get the present weather out of the way quickly.  A front will be moving through northern Utah this morning, with the accompanying precipitation just about to move into the Salt Lake Valley at 8 am MST. Source: NCAR/RAL Typically a radar image like that in early March would be cause for extreme alarm as snow moves in during the morning rush hour, but alas, this year is not normal and instead we'll see rain during this event with perhaps a few flakes on the upper benches as it winds down.  There will be a few inches of snow for the mountains. Now, let's look back at the past weather and build upon yesterday's "image of the day," which showed the remarkable increase in snowpack in February at Tony Grove Lake in the Logan Area Mountains. Source: NWS/NRCS During February, Tony Grove Lake and the northern Utah mountains down to about Mount Timpanogos were on the southern periphery of a remarkable corridor of heavy snow.  Many areas of western Monta...

Source: NWS and NRCS An increase of 20+ inches in snowpack SWE in a month in the Logan Area Mountains.

A nearly snow free Kimball Junction, 2 March 2014 With an interesting February in the record books, I thought we would take a look back on the month and think about it in the context of the climate change that is anticipated in the coming century. Based on observations from the Salt Lake City airport, February 2014 was very mild.  Only three days had minimum temperatures below average and only 6 had maximum temperatures below average. Source: NWS For the month, the average temperature was 42.2ºF, 7.9ºF above the average for 1981–2010.  In terms of precipitation, we received 1.57 inches, which is about 25% more than average.  In terms of snowfall, we got only 2.1 inches compared to an average of 10.7 inches. And what about the snowpack?  Snow in the Salt Lake Valley was obliterated, as well as the snow at Mountain Dell, a popular area for cross country skiing.  The month was pretty much a disaster for snow at and below 7000 feet in the central Wa...

Orographic clouds over Lone Peak, Saturday, 1 Mar 2014 It's been a great storm cycle thus far.  We are now looking at a total of 21 inches of snow at Alta-Collins since Thursday morning with 2.78 inches of water.  The stuff that fell last night and this morning was especially dense with 10" of snow containing 1.42" of water for a 14.2% water content.  One look at the highly scientific sample of snow collected by my open door's arm rest this morning at Snowbird pretty much shows why.  Those nasty looking orographic clouds in the photo above were laying down nothing but graupel. You can also see the small graupel in the real-time data (12:05 PM MST) collected by the University of Utah MultiAngle Snowflake Camera (MASC), provided by Alta on their Snowflake Showcase . Source: University of Utah/Alta Ski Area This collaborative effort between the U and Alta provides real-time photos of snowflakes (or in this case snow pellets) up at Alta.   A few...