Wasatch Weather Weenies

The Silly Season is upon us when prognosticators spouting an alphabet soup of climate phenomena (e.g., ENSO, PDO, NAO, etc.) make claims for what this ski season will be like. As far as northern Utah is concerned, ignore all this crap.  The correlations are low.  The useful skill is non-existent.  Yeah, I know there is a 70% chance of El Nino.  Who cares.  Nobody knows what kind of ski season the Wasatch are going to have.  Nobody.  This is why I call it the silly season .  Here's my official forecast, previewed on twitter a couple of weeks ago. There, I feel better now.

Yesterday's imagary from the Suomi NPP satellite shows how northern Utah has been in the crosshairs of plumes from fires further upstream, especially California.  PM2.5 concentrations at Hawthorne Elementary have been in the moderate to unhealthy for sensitive groups categories for about 48 hours, and in the moderate category at times for several day before that.  This is one of the worst stretches of smoke that I can remember and I've developed a persistent cough in the last couple of days.  Dry, clean, cool air is desperately needed!

Motivated by an intriguing tweet by University of East Anglia Professor Tim Osborn , I thought we would compare global temperatures for July of 1960, which was the warmest 20th century July at the Salt Lake City International Airport to July of 2018, which was the 5th warmest on record and also feature remarkable temperatures in many regions across the Northern Hemisphere.  The graph below illustrates the anomalous warmth of July 1960 as well as the recent string of very warm Julys in the 21st century.  Source: NOAA Regional Climate Centers For convenience, I am going to examine the surface temperature departure (or anomaly) from the 1981-2010 average from the NCEP/NCAR reanalysis for the two Julys.  There are better datasets for doing a surface temperature comparison, but the differences are not going to be all that significant. In July 1960, anomalous warmth covered much of the western continental U.S. and southwest Canada, with the most anomalous temperature...

A little something to get you going on this August 1st as we put July in the rear view mirror and begin to look forward to cooler times. The weather this July can best be described using words like ugly and heinous.   At the Salt Lake City International Airport, the mean temperature for the month was 83.1˚F, tied for 5th warmest all time.   Source: NOAA Regional Climate Centers And here's a factoid for you.  The 11 warmest Julys have all happened in the 21st century.  People in Salt Lake simply didn't suffer like this in the 20th century.  If you go back to Y2K, the hottest July on record was 81.2˚F (1960).  Now, it is 85.3˚F (2017).  Source: NOAA Regional Climate Centers Digging in beyond the mean monthly temperature, the mean maximum and mean minimum for the month were 95.5˚F and 70.7˚F, respectively.  The former only rates as the 14th warmest on record, but the latter is the 3rd warmest.  Minimum tempera...

There are dramatic differences in air pollution episodes over the Salt Lake Valley between winter and summer. During winter, when the sun angle is low, we frequently lack sufficient surface heating to warm the atmosphere and develop a deep layer in which turbulence can mix the near-surface air with the atmosphere aloft.  The layer in which that turbulence occurs, which is known as the boundary layer (or mixed layer) , can be very shallow.  As a result, emissions from our urban area are trapped in the valley, leading to elevated particular matter concentrations. An example is the inversion event of late December 2016.  As can be seen in the photo below, taken on the afternoon of 30 December, smog is confined primarily to the valley and the visibility improves dramatically with altitude.  Typically in these instances, one can find clean air simply by going to the mountains. A sounding taken that afternoon at the Salt Lake Airport is very typical of of winterti...

" The old records belong to a world that no longer exists " - Dr. Marty Hoerling, Research Meteorologist NOAA Earth Systems Research Laboratory It has been a remarkable summer across the Northern Hemisphere, with high-temperature records being set at locations in North America, Asia, Europe, and North Africa.  Now that we are well into the fire season, a pall of smoke generated by large wildfires hangs over much of the western United States, as evident in yesterday afternoon's GOES-16 satellite image.   Source: CIRA Will we ever return to normal? No. Although the climate, especially on regional scales, has always exhibited variability, we are now accelerating into a future in which the planet will be warming at a rate not seen since the emergence of human civilization.  Further, while this warming may occur in fits and starts rather than at a steady rate, the idea that what we are currently experiencing is "just a cycle" is pure fantasy...

Thermal anomalies (red) and smoke from the Carr Fire as seen from Aqua/MODIS 26 July 2018 A catostrophic situation is unfolding in northern California where the Carr Fire is threatening communities in and around Redding. The latest incident information from Cal Fire indicates that as of 9:17 AM this morning (27 July), the Carr Fire has burned 44, 450 acres, destroyed 65 structures, and damaged 55 structures.  Only 3% contained, the fire is currently threatening almost 5,000 structures, with numerous evacuations and road closures.  News reports indicate that the fire has now claimed the lives of two firefighters . News footage of the fire is simply unbelievable.  Below are a couple of perspectives on rotating updrafts associated with the fire. No, this is not a tornado. The Carr Fire in Shasta County created this rotation updraft. #CarrFire #California pic.twitter.com/CVvcafJBGK — ABC10 (@ABC10) July 27, 2018 Timelapse video shows the #CarrFire approa...