The Priest River Experiment Station, located about 50 miles NE of Spokane, has recorded climate data nearly continuously since its establishment 100 years ago in 1911.
This station has been well maintained with a good exposure over grass in a rural environment far removed from UHI effects.
Page 14 of this history shows the weather station 76 years ago in 1935:
Here is Bob Meyer’s 2007 site survey published at Anthony Watts’ surfacestations.org:
http://gallery.surfacestations.org/main.php?g2_itemId=12655
The StationSurvey notes make interesting reading.
Over those 100 years from 1911-2010 the warmest April was in 1934 with an average temperature of 52.1 F and the coldest was in 2008 with an average temperature of 37.9 F.
The warmest year was 1934 with 47.4 F and the coldest year was 1916 with 40.2 F. The warmest year in the past 20 years was 1998 with 46.3 F.
More data can be found here:
http://www.wrcc.dri.edu/cgi-bin/cliMAIN.pl?id7386