Most US Station All-Time Record Maximum Temperatures Were Set Prior To 1940
'There are 863 USHCN (U.S. Historical Climatology Network) stations which have been continuously active since at least 1930. The majority of them recorded their all-time record maximum temperature prior to 1940.'
Since 1999, NASA and NOAA have tried to delete the hot 1930′s from the US temperature record, because it doesn't suit their agenda.