Seasonal Fraction of Annual Precipitation

This map shows the percentage of annual precipitation that occurs during the indicated 3-month season, based upon climatological precipitation using the 1991-2020 base period from the monthly CPC Merged Analysis of Precipitation (CMAP) dataset.

Regions shaded in green receive more than 30% of their annual precipitation, while areas shaded in brown receive less than 20% of their annual precipitation during the indicated 3-month season. Light blue represents fractions of annual precipitation between 20% to 30%. Contours are drawn at intervals of 10%. Masked areas in white indicate regions that receive less than 25 mm of precipitation during the 3-month season shown. The tool allows the selection of any of the 12 overlapping 3-month seasons during the year.

Dataset Documentation

Seasonal Fraction of Annual Precipitation

CPC Merged Analysis of Precipitation (CMAP) Version 2 (using rain gauge and satellite estimates), January 2012 release, on a 2.5° lat/lon grid
Data Source
NCEP, Climate Prediction Center (CMAP January 2012 release)
Percentage of annual climatological precipitation that occurs during any 3-month season of the year, using the 1991-2020 climatological base period


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