The number of days over 100F at DFW reported by the National Weather Service has been increasing and peaked in 2011.
But at Weatherford, which is a reasonably well sited rural station west of Fort Worth, 100 degree days peaked in 1980 and have been declining long term.
ftp://ftp.ncdc.noaa.gov/pub/data/ghcn/daily/hcn/USC00419532.dly
