The late John Daly has prepared a great many temprature-time plots from rural and remote weather station temperature records which show little change in annual mean temperature for long periods of time. In some cases the records start before 1900.

GO: http//www.John-Daly.com., scroll down and click on "Station Temperature Data". In particular check the plot for Death Valley. Also read his article,
"What the Station Say".

PBS: Check out the temp records for Dodge City and Tombstone.