I found Austin records that goes back to the 1850s. I wish Houston NWS had data like this.
Temperature (1854-2010)
http://www.srh.noaa.gov/images/ewx/aus/attmontemp.pdf
Rainfall (1856-2010)
http://www.srh.noaa.gov/images/ewx/aus/attmonrain.pdf
It is from Camp Mabry. I wish the Houston NWS had records like this.