Helena Montana Climate Data

Monthly Average Climate Data for Helena Montana

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January14.8 °F33.5 °F0.56 in.
February16.9 °F37.2 °F0.61 in.
March23.2 °F46.3 °F0.67 in.
April30.6 °F55.1 °F1.24 in.
May39.0 °F64.7 °F2.09 in.
June46.1 °F73.1 °F2.28 in.
July51.8 °F84.2 °F1.28 in.
August49.9 °F83.6 °F1.09 in.
September42.2 °F72.1 °F1.19 in.
October32.8 °F56.9 °F1.0 in.
November23.6 °F42.7 °F0.78 in.
December15.6 °F33.7 °F0.57 in.
Annual32.2 °F56.9 °F13.36 in.

Climate Data for Helena Montana

Average First Frost DateSep. 21 - Sep. 30
Average Last Frost DateJun. 1 - Jun. 10
Average Days With FrostOver 180 Days
Plant Hardiness Zone - 2023Zone 5a : -20°F to -15°F
Plant Hardiness Zone - 2012Zone 4b : -25°F to -20°F
Current Drought ConditionsSevere Drought
Köppen Climate ClassificationDfb - Humid Continental Mild Summer, Wet All Year
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