Historical Palmer Drought Indices
Monthly maps of drought conditions in the contiguous U.S. as measured by the Palmer Drought Severity Index, Palmer Hydrological Drought Index, Palmer Modified Drought Index, and Palmer Z-Index (Palmer, 1965) are provided for January 1900—November 2014. Animations of any set of monthly maps for any period desired can be viewed by selecting the beginning and ending dates of interest.
NCDC added Alaska climate divisions to its nClimDiv dataset on Friday, March 6, 2015, coincident with the release of the February 2015 monthly monitoring report. For more information on this data, please visit the Alaska Climate Divisions FAQ.
Palmer Hydrological Drought Index