Index Washington Climate Data

Monthly Average Climate Data for Index Washington

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January33.0 °F43.9 °F12.42 in.
February33.3 °F47.5 °F8.36 in.
March35.3 °F51.9 °F9.14 in.
April39.1 °F58.4 °F7.32 in.
May45.0 °F65.8 °F4.91 in.
June49.1 °F69.8 °F4.05 in.
July52.9 °F77.0 °F1.6 in.
August52.8 °F77.9 °F1.73 in.
September48.7 °F71.2 °F4.16 in.
October42.6 °F58.8 °F9.12 in.
November36.8 °F49.0 °F13.73 in.
December32.8 °F42.8 °F11.63 in.
Annual41.8 °F59.5 °F88.17 in.

Climate Data for Index Washington

Average First Frost DateOct. 21 - Oct. 31
Average Last Frost DateMay 11 - May 20
Average Days With Frost75-100 Days
Plant Hardiness Zone - 2023Zone 8b : 15°F to 20°F
Plant Hardiness Zone - 2012Zone 8a : 10°F to 15°F
Current Drought ConditionsAbnormally Dry
Köppen Climate ClassificationCsb - Warm-Summer Mediterranean Climate