At first glance I also thought it was somewhere in eastern WA, but the precipitation pattern is different there.
Alright, hopefully this one is a decent challenge... metric in parentheses
Jan: 38/20 4.5" (3/-6 11cm)
Feb: 41/22 4.8" (5/-5 12cm)
Mar: 49/30 6.1" (9/0 15cm)
Apr: 58/38 5.4" (14/3 13cm)
May: 66/47 6.1" (19/8 15cm)
Jun: 72/54 5.7" (22/12 14cm)
Jul: 75/58 5.8" (24/14 14cm)
Aug: 74/57 5.6" (23/14 14cm)
Sep: 68/51 5.8" (20/10 14cm)
Oct: 59/41 5.4" (15/5 13cm)
Nov: 51/33 5.6" (10/0 14cm)
Dec: 42/24 4.4" (5/-4 11cm)