1991-2020 Monthly Precipitation Normal Maps

A common misconception is that a climate "normal" describes the "typical" state of the atmosphere. "Normal" is simply a 30-year arithmetic mean, computed once per decade. The precipitation normals data presented in the maps below summarize the observation period 1991-2020. These values are benchmarks to be used throughout this decade as a measure of central tendency. Normals data can be useful in placing ongoing weather conditions in historical context. Additionally, normals data offer an excellent tool for describing climate variability across space. Clicking on any of the maps below will bring the user to a page that provides a larger version of the normal precipitation map, as well as links to *.zip files containing the map in a variety of formats (*.jpg, *.wmf, *asc).

Normal January PrecipitationJanuaryNormal February PrecipitationFebruaryNormal March PrecipitationMarch
Normal April PrecipitationAprilNormal May PrecipitationMayNormal June PrecipitationJune
Normal July PrecipitationJulyNormal August PrecipitationAugustNormal September PrecipitationSeptember
Normal October PrecipitationOctoberNormal November PrecipitationNovemberNormal December PrecipitationDecember
Normal Annual PrecipitationAnnual (Jan-Dec)


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