Shelby, MT Climate

Climate Insight: Shelby, MT

The NOAA 1991–2020 climate normals describe Shelby, Montana as a location with an annual average temperature of 42°F, ranging from a mean daily high of 56°F to a mean daily low of 29°F. July is typically the warmest month of the year, while January is the coldest. These thirty-year averages, computed from station USC00247500, smooth out year-to-year variability and give a baseline expectation for typical conditions in any given month.

Precipitation patterns matter as much as temperature for anyone planning to live, garden, or travel here. Shelby receives roughly 12.1 inches of precipitation each year, with 38.9 inches typically falling as snow. The frost-free season averages 116 days, which directly shapes the planting calendar and growing potential for the area, with the last spring freeze near May 23 and the first fall freeze near September 16. For energy use, 8,532 heating degree days and 242 cooling degree days tell the story of how often furnaces and air conditioners run during a normal year.

On PlainClimate's composite comfort index, Shelby 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.