Marietta, OK Climate

Climate Insight: Marietta, OK

In Marietta, Oklahoma, the NOAA 1991–2020 climate normals put the annual average temperature at 62°F, ranging from a mean daily high of 74°F to a mean daily low of 49°F. July is typically the warmest month of the year, while January is the coldest. As thirty-year averages computed from station USC00345563, these numbers smooth out year-to-year noise into a working baseline for a typical month.

Beyond temperature, Marietta averages 39.8 inches of precipitation annually, with 3.8 inches typically falling as snow - a real factor for anyone planning to live, garden, or travel here. The frost-free season averages 210 days, which directly shapes the planting calendar and growing potential for the area, with the last spring freeze near April 6 and the first fall freeze near November 2. Turning to energy use, 3,233 heating degree days and 2,007 cooling degree days tell the story of how often furnaces and air conditioners run during a normal year.

On PlainClimate's composite comfort index, Marietta scores 93/100 (Excellent), a blended measure that weighs temperature mildness, precipitation moderation, and extreme-weather frequency against one another. The monthly tables above turn that into a planning tool: expect the mildest highs and lows in the shoulder seasons, July-driven heat at the peak of summer, and January-driven cold at the depth of winter. Every number here is a thirty-year average, not a forecast, so any given year can and does run warmer, cooler, wetter, or drier than the normal.