Clim. Monitoring / Climate-2003 / May / U.S. Regional Drought / Help

Climate of 2003 - May
Colorado Drought

National Climatic Data Center, 13 June 2003

Overview / Paleo Perspective

Top of Page Overview

Statewide Precipitation Ranks
for Colorado , 2002-2003
Period Rank
May 48th driest
Apr-May 52nd driest
Mar-May 30th wettest
( 80th driest)
Feb-May 18th wettest
( 92nd driest)
Jan-May 27th wettest
( 83rd driest)
Dec-May 40th wettest
( 69th driest)
Nov-May 45th wettest
( 64th driest)
Oct-May 43rd wettest
( 66th driest)
Sep-May 30th wettest
( 79th driest)
Aug-May 43rd wettest
( 66th driest)
Jul-May 48th driest
Jun-May 36th driest
 Graphic showing Colorado statewide precipitation departures, January 1998 - present
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Graphic showing Colorado statewide Palmer Z Index, January 1998 - present
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Graphic showing Colorado statewide precipitation, May 1895-2003
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Graphic showing Colorado statewide Palmer Hydrological Drought Index, January 1900 - May 2003
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Top of Page Paleoclimatic Perspective

Colorado experienced extremely dry conditions during the last two to three years. Southeastern Colorado was especially dry, with the Palmer Hydrological Drought Index reaching the lowest levels seen in the last 100 years (see top graph to right).

A tree-ring composite chronology was prepared to extend the drought record for this area back to the 16th century. This proxy index was prepared from standard tree-ring chronologies at Valley View Ranch, Mesa de Maya, and Sheep Pen Canyon and correlates well with southeast Colorado May PDSI over the period 1925-1990. The composite chronology covers the period 1534-1997 and is shown in the bottom graph to the right.

Graph showing reconstructed Southeast Colorado Precipitation Chronology, 1000-2003
larger image (75 K)

larger image (170 K)

Both the top and bottom graphs show the 1930s and 1950s droughts well. The top graph indicates that the PHDI in 2002 reached levels drier than the 1930s and 1950s droughts, which are the worst droughts of the 20th century. However, the tree-ring composite chronology suggests that droughts more severe than the 1930s and 1950s have happened in the past. Of particular interest are the remarkable low growth periods in the mid 19th century and in the 1660s and 1680s.

For data, see: Paleoclimatology / Tree Ring.

For further questions on these data or this research, please contact Connie Woodhouse at NOAA's Paloclimatology Program.

Clim. Monitoring / Climate-2003 / May / U.S. Regional Drought / Help