Hebgen Dam, MT Climate

Climate Insight: Hebgen Dam, MT

The NOAA 1991–2020 climate normals describe Hebgen Dam, Montana as a location with an annual average temperature of 37°F, ranging from a mean daily high of 50°F to a mean daily low of 25°F. July is typically the warmest month of the year, while January is the coldest. These thirty-year averages, computed from station USC00244038, smooth out year-to-year variability and give a baseline expectation for typical conditions in any given month.

Rainfall (and snow, where it falls) shapes day-to-day life here as much as temperature does. Hebgen Dam sees about 28.6 inches of precipitation a year, with 177.2 inches typically falling as snow. The frost-free season averages 87 days, which directly shapes the planting calendar and growing potential for the area, with the last spring freeze near June 15 and the first fall freeze near September 10. On the energy side, 10,200 heating degree days and 32 cooling degree days tell the story of how often furnaces and air conditioners run during a normal year.

On PlainClimate's composite comfort index, Hebgen Dam scores 44/100 (Moderate), a blended measure that weighs temperature mildness, precipitation moderation, and extreme-weather frequency against one another. Use the monthly tables above to plan around specific windows, shoulder seasons for mild highs and lows, peak summer for July-driven heat, or deep winter for January-driven cold. All figures here are thirty-year averages: any single year may run warmer, wetter, drier, or cooler than the normal, so treat them as planning guidance rather than forecasts.