*source: national centers for environmental information (NCEI)Mean indicates the mean of daily mean temperatures for that month (mean of means), Max and Min are the mean of daily maximum and minimum temperatures for that month.

Note: The measurements above come from the Portland International Airport weather station, with the exception of October 2013, absent from the original dataset. Mesurement for Oct 2013 were obtained from the Troutdale (OR) Airport weather station, located 12 miles east of PDX weather station.