Williamsburg, IA Climate

Climate Insight: Williamsburg, IA

Based on station USC00139067 feeding NOAA's 1991–2020 climate normals, Williamsburg, Iowa averages 48°F a year, ranging from a mean daily high of 59°F to a mean daily low of 38°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.

Williamsburg averages 37.7 inches of precipitation a year, with 28.1 inches typically falling as snow, and that matters as much to daily life here as temperature does. The frost-free season averages 164 days, which directly shapes the planting calendar and growing potential for the area, with the last spring freeze near April 28 and the first fall freeze near October 9. As for energy demand, 6,866 heating degree days and 785 cooling degree days tell the story of how often furnaces and air conditioners run during a normal year.

On PlainClimate's composite comfort index, Williamsburg scores 59/100 (Moderate), 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.