Yesterday, June 22,  2018, the mercury officially hit 100°F at DFW Airport. This marks the first time of the summer 2018 season that the temperature hit the century mark. The last time DFW Airport hit 100°F was last August 19, 2017. This did not affect the record for the date which still remains as 103°F set in 1953. This is also a few weeks ahead of the average first 100 degree date, which typically occurs in mid-July. We average about sixteen 100 degree days per summer season.