Wasatch Weather Weenies

Residents of the northern Wasatch Front and northern Salt Lake Valley were treated to some natural air conditioning thanks to a complex of thunderstorms that moved across the area yesterday evening.   Source: ral.ucar.edu Some of the thunderstorms were severe and produced wind gusts of 60 mph in Sugarhouse, 64 mph in Tremonton, and 72 mph at the I215/I80 exchange.   There was also beneficial rain and cooling. Temperatures at the Salt Lake City International Airport dropped to 67°F, the lowest temperature observed there since July 4, and I was able to get temperatures in my house below 70°F for the first time since we returned from Austria.   We were also treated to a beautiful double rainbow as the storm moved off to the east.   Unfortunately, as has been forecast for a few days, the heat is expected to return in spades by the weekend, with the National Weather Service issuing an Extreme Heat Watch for SaturdayAfternoon through Sunday Evening with...

Yesterday (Monday) morning's minimum temperature at the Salt Lake City Airport was an incredibly warm 85°F.  Daily records though are based on the minimum and maximum temperatures over the period from midnight to midnight local standard time and last night temperatures dropped to 82°F by midnight local standard time (1 AM MDT), so that stands as the minimum temperature for the day.  Still 82°F ties for the highest minimum temperature at the Salt Lake City International Airport.  Other days that only cooled to 82°F are 23 July 2023 and 13 July 2021.   The top 20 highest minimum temperatures in the Salt Lake City area are below.  17 of them are in the 2000s, which likely reflects multiple factors including climate change, urban growth, and local conditions at the observing sites. Source: https://xmacis.rcc-acis.org/ All occurred though between July 3rd and 31st.  More evidence of the misery of July.

I heard a Catholic priest say in downtown Salt Lake City this weekend that the weather is "Hotter than Hell."  Who am I to argue with a man of the cloth? That said, let's take a quick look at the data and forecast as we approach the end of July. The month actually started out with four days with minimum temperatures between 62 and 66 at the Salt Lake City International Airport.  And believe it or not on July 22nd, we actually had a maximum of only 87°F.  Other than thoat, it's been hot.  Since July 4th, every day but one has had a minimum temperature at or above 70°F and there have been nine days with a maximum temperature at or above 100°F, including the all-time record high of 109°F on July 12th.   For the first 25 days of the month, the mean temperature at the Salt Lake City International Airport was 85.3°F.  This is not a record, but it is 4th all-time in the Salt Lake City area and 4.2°F higher than any equivalent period in the 20th century. ...

I've been wondering for some time if snow storage will come to Utah, even posting on the possibility ten years ago (see Is Snow Storage Coming to Utah ).   It finally has come, but to a place I didn't expect, the Soldier Hollow Nordic Center (SoHo). If you walk around the center, you might spy a whale of white a bit to the southwest of their day lodge.  As you approach, you'll see an insulated mat manufactured by a company called Snow Secure covering about 60,000 cubic meters of snow.   Last February, Soldier Hollow put eight snowguns in this area and made snow whenever they could for a few weeks.   That snow was then piled high by snowcats.  Even now, in late July, the pile is perhaps as much as 15 feet high in the center.   SoHo is hoping that 80% of the snow they put under the mat will still be around by mid November for them to spread out on about a kilometer cross country trail, enabling them to open early and focus snowmaking effo...

In the wake of recent tragedies, it's worth a bit of review of flood and lightning safety.  In the case of floods, here's some data from the National Weather Service and their partners: More deaths occur due to flooding than any other thunderstorm hazard. Over half of all flood-related drownings occur when a vehicle is driven into flood waters. The next highest percentage of flood-related deaths is due to walking into or near flood waters. Source: National Weather Service A full run-down of National Weather Service flood products, including outlooks, watches, advisories, and warnings is available at  https://www.weather.gov/safety/flood-products .  In Utah, the National Weather Service also provides flash flood potential ratings for southern Utah and covering 12 recreation areas at  https://www.weather.gov/slc/flashflood .   As evident in near the Cottonwood Fire and Beaver, fire scars can be especially problematic for flash flooding and debris flows. ...

Sadly there were six weather-related fatalities in Utah on Friday and Saturday.  A man was killed after being stuck by lighnting on the American Fork Twin Peaks at around 12:20 PM .   We hiked up Snowbird that morning, reaching the summit around 11 AM.  There were a few sprinkles around at that time.  When we reached our vehicle at around 11:30 we heard the first rumble of thunder.  The strongest radar reflectivity in the Snowbird/American Fork Twins area was observed at 12:02 PM.  It was a fairly small scale cell.   Source: https://weather.ral.ucar.edu/ Three lightning strikes were observed on the Alpine ridge yesterday (orange dots below).  One was just south of the American Fork Twin.   Source: lightningmaps.org Given uncertainties in strike geolocation, that may have been the one.   On the prior day in southern Utah, a family of five were killed in a flash flood at a campground near Bicknell .   The...

Mid July is here and it's worth a look at the Great Salt Lake.  Satellite imagery from July 11, when northern Utah was cloud free, showed considerable lake bed exposed in the Bear River and Farmington Bays.   Source: https://worldview.earthdata.nasa.gov/ Elevation data shows that both the north and south arms had early and broad peaks in April and began to decline in earnest around mid May.  The north arm currently sits at an elevation fo 4190.5 feet and the south arm at 4190.9 feet.  Each of these above their respective record minimums in 2002, which were a bit below 4189 feet.  It's unlikely we will get down that low this year, but getting below 4190 seems to be in play.   Source: https://greatsaltlake.utah.gov/current-conditions Next winter will be critical for whether or not we end up flirting with a record minimum again.  There are good reasons to root for a good snow year besides skiing. 

The Salt Lake City International Airport reached 109°F today (Sunday, July 12), setting a new all-time record for the site.   If you are wondering, 20.4°C was observed at 700-mb in the 0000 UTC (1800 MDT) sounding, which is also the highest observed in the sounding records (the old record was 20.2°C).   It really was a dry heat.  At the time of the 109°F, the dew point was 26°F, resulting in a dewpoint depression of a remarkable 83°F and a relative humidity of 6%. Stay hydrated my friends.

Forecasts for the next several days show the development of a strong ridge of upper-level high pressure over the north-central United States.  The GFS forecast valid 0000 UTC 14 July (1800 MDT Monday) shows 500-mb heights above the dreaded 6000-m level centered over Minnesota with anomalously high heights across most of the continental United States.   Source: pivotalweather.com This is a recipe for extreme heat to affect a good chunk of the continental United States, beginning in portions of the interior western US today and this weekend.  Currently, extreme heat warnings are in place for an area spanning from Utah to North Dakota and I suspect we will see warnings spreading farther east across the northern tier of the continental United States as the ridge fully develops.  For northern Utah over the next few days I'll invoke my 20/20 rule here for recognizing temperature extremes.  The 20/20 rule says that anything above 20C at 700-mb (10,000 feet) is exc...

I wish I could say I'm glad to be back in Utah, but the aridity and dust leave much to be desired. Yesterday at around 2000 MDT strong outflow wind from convection north of Salt Lake City picked up dust and briefly caused a spike in PM25 in some areas of the Salt Lake Valley.  Below is a photo of the dust looking south from the upper Avenues at 2007 MDT. Observations from the University of Utah show a spike in PM2.5 to almost 40 ug/m3 at 2020 MDT.   Source: MesoWest There's a good chance that the exposed bed of the desiccating Great Salt Lake was a contributor to some if not most of the dust in this event.  

We made it back to Salt Lake City today (Wednesday, July 8).  We stayed a few days in Amsterdam on the way home.  It's a little known fact that I was born in Amsterdam (Amsterdam, New York, not the big one in The Netherlands), so I always wanted to visit my hometown's namesake.   Amsterdam (the one in The Netherlands) is a real bike-friendly and bike-oriented city.  "Parking lots" are full of them.   Spending time in Europe makes you realize that US cities are really built for cars not humans.   I am a fan of Dutch painters and did enjoy spending some time at the Rijkmuseum.  A lot of paintings caught my eye, but two that had a weather or climate theme are below.  The first was Dutch Ships in a Calm Sea by Willem van de Velde II because he did such a great job with the clouds.   The second was Winter Landscape with Ice Skaters by Hendrick Avercamp because it's related to winter!   Dutch canals still freeze over s...

Andrea and I left Innsbruck on the 1st of July and are working our way back to Salt Lake.  For our last day in Innsbruck we actually went to Germany.  Mittenwald to be specific, which is just across the Austrian-German border.   We were beat from hiking so we needed an easier day.  The train ride from Innsbruck to Seefeld, Mittenwald, and finally Garmisch-Partenkirchen if you go that far is a really wonderful ride.  The ascent out of Innsbruck offers many great views of the Inn Valley and Kalkogel Alps, pictured below.   The train is almost always filled with hikers and cyclists.  It's easy to throw your bike on in Innsbruck and take it up to Seefleld or one of the surrounding villages for a good ride.  Long mountain bikes in the the Karwendel Alps are also possible.   Austria invests in their children.  They have a strong public school system and provide a lot of great opportunities.  We were joined on the train by a...

During the European heat wave we decided to escape to higher altitudes and spent a long weekend in the Dolomites, basing out of Wolkenstein in Gröden/Selva in Val Gardena, which is about 3 hours from Innsbruck by regional rail and bus.  Wokenstein/Selva is in South Tyrol (Süd Tirol in German) and was part of the Hapsburg Empire and "County of Tyrol" for more than 500 years.  After World War I, South Tyrol was annexed by Italy.  Under Mussolini, there were efforts to "Italianize" the region.  Cities were given Italian names and both German and Italian names are used today.   Following WWI, South Tyrol has had a complicated relationship with Italy, but today is an autonomous region with considerable self-governing powers.  It is also one of the wealthiest regions of the EU with low poverty rates.  Many people in the region are multilingual, speaking German, Italian, English, and in some cases Ladin, which is still spoken by some families around the ...