Sunday, July 1, 2012

June In Review

June is in the books.  It was a month without measurable rain at the Salt Lake City International Airport, with just a trace falling on the 2nd and 5th.  It has now been 35 days since the last measurable precipitation on May 27th.  The record by the way is 63 days (Sep 11 – Nov 12 1952).   To get into the top 10 we need to get to 39 days.  We have a shot at that, although there is a slight chance that we'll get some monsoon moisture and maybe some scattered showers and thunderstorms on Thursday.

The average temperature was 73.6ºF, 3.9ºF above the 1971–2000 average.  Using the evaporative cooler or air conditioning a lot?  We had 301 cooling degree days, 114 more than average.

Although a bit simplistic, the Palmer Drought Severity Index uses rainfall and temperature to evaluate drought severity.  Using this index, the US Drought Monitor presently classifies Utah as being abnormally dry or in extreme drought depending on location.

A non-scientific assessment might classify the current situation as crispy.


  1. Do you find it odd that the record dry streak was Sep-Nov? I would've thought that it would have likely occurred a few months earlier, given the summer climatology of upper-level ridging. Oh well, maybe we'll change that...

  2. What was the difference climatologically 50,000 to 30,000 years ago compared to present time that allowed a much wetter climate here in Utah?

  3. Looking at the list it appears that the longest dry periods for SLC are somewhat bi-modal, mostly either early-mid summer, or in the fall. This makes some sense since early summer has a strong climatological precip minimum centered about the beginning of July. In autumn there is commonly strong ridging also, and after mid September there is usually a lack of convection associated with these ridge situations. Also many cold frontal passages that occur in Sept/Oct are dry fronts as the storm track is relatively far to the north.