A Lack of Moisture

My friends of Meteorological Solutions Inc. sent me some remarkable observations taken near Milford, Utah yesterday.  It is hard to imagine a lower atmosphere completely devoid of water vapor, but yesterday in Milford is probably as close as you can get.  The observations taken ~1700 MDT (2300 UTC) show an hourly average temperature of 82.6ºF/28.1ºC and a Relative Humidity of 0.427%, yielding a dewpoint of -42.3ºF/-41.3ºC and a dewpoint depression of 125ºF/69.4ºC.

That's the big 125 in Fahrenheit!  I don't have an encyclopedic memory, but good luck finding something bigger than that.  Maybe in the central Sahara, the Empty Quarter, or Death Valley?  Incredible.