download data:
http://water.weather.gov/precip/p_download_new/2011/06/28/

http://prism.oregonstate.edu/pub/prism/us/grids/tmax/
http://prism.oregonstate.edu/pub/prism/us/grids/tmin/
http://prism.oregonstate.edu/pub/prism/us/grids/tdmean/