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U.S. Gridded Standardized Precipitation Index (SPEI) from nClimGrid-Monthly

Associated Agencies

National Oceanic and Atmospheric Administration's (NOAA) National Centers for Environmental Information (NCEI)

The U.S. Gridded Standardized Precipitation Evapotranspiration Index (SPEI) is derived from the nClimGrid-Monthly dataset and includes timescales of 1, 2, 3, 6, 9, 12, 24, 36, 48, 60 and 72 months.  The nClimGrid-monthly dataset is a gridded dataset derived from spatially interpolating data from the Global Historical Climatology Network (GHCN), starting in 1895.

The SPEI is available with both the gamma and Pearson Type III types of distribution fittings, using the Python Drought Indices open-source package.


How to use this site:


SPEI from nClimGrid-Monthly in NetCDF: Available for download from NOAA/NIDIS/NCEI