Texas: Bogus high temperature readings

Guest Post By Richard Berler Chief Meteorologist KGNS TV Laredo, TX | Climate Science: Roger Pielke Sr.

Recently (May 2011), the daytime maximum temperatures from the AWIS jumped to well over 4F above my MMTS.
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The NWS came down to Laredo, and on camera, we approached the AWIS instrumentation and made our own temperature measurements and verified that the AWIS was running close to 5F too high during the afternoon hours. The heat of the NWS and a television news story finally prompted the FAA folks to put a replacement unit into operation at the AWIS site. The impact was immediate, and also verified that the earlier day and night 2F bias that I suspected earlier was also correct. Here’s the Tmax (AWIS-MMTS), Tmin (AWIS-MMTS) this year (July not shown as the replacement unit was deployed mid month: Jan 2.2,2.4 Feb 1.9,2.4 Mar 2.2,2.1 Apr 2.3,1.7 May 4.3,1.9 June 4.7, 1.6 Aug 0.6,0.0 Sep 0.5,-0.1.

Remarkably, when the NWS office wanted to go in and eliminate the myriad of record high temperatures that had been generated by the AWIS during the time that it had been commissioned/certified as official in 2009 (and especially the May and June data from 2011), the southern region office in Fort Worth told them to leave it alone, let it stand. I am astounded at this attitude.