Swan Lake, MT Climate

Climate Insight: Swan Lake, MT

Based on station USC00248087 feeding NOAA's 1991–2020 climate normals, Swan Lake, Montana averages 44°F a year, ranging from a mean daily high of 55°F to a mean daily low of 32°F. July is typically the warmest month of the year, while January is the coldest. Because these figures are thirty-year averages rather than any single year's readings, they describe the typical month, not a forecast for it.

Swan Lake averages an uncharted amount of precipitation a year, predominantly as rainfall, and that matters as much to daily life here as temperature does. The frost-free season averages 125 days, which directly shapes the planting calendar and growing potential for the area, with the last spring freeze near May 17 and the first fall freeze near September 19. As for energy demand, 7,953 heating degree days and 142 cooling degree days tell the story of how often furnaces and air conditioners run during a normal year.

On PlainClimate's composite comfort index, Swan Lake scores 39/100 (Below Average), a blended measure that weighs temperature mildness, precipitation moderation, and extreme-weather frequency against one another. For planning purposes, look to the monthly tables above: shoulder seasons bring the mildest highs and lows, summer brings July-driven heat, and deep winter brings January-driven cold. Treat every figure here as a thirty-year average rather than a forecast - individual years routinely run warmer, cooler, wetter, or drier than the normal.