Weather and Climate Impacts on Water Supply Nolan Doesken Colorado Climate Center Atmospheric Science Department Colorado State University http://ccc.atmos.colostate.edu Presented at the South Platte Forum, Longmont, CO, October 26, 2005 Prepared by Odie Bliss
Water Year 2005 temperature departures from 1971-2000 average Water Year 2005 10.0 8.0 Departure (Degrees Fahrenheit) 6.0 4.0 2.0 0.0-2.0-4.0 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Eastern Plains Foothills Mountains Western Valleys
2000 2005 33 31 29 27 25 23 21 19 17 Colorado Statewide Winter Temperature Average Colorado Statewide Average Winter (Dec-Feb) Temperature Temperature Average Temperature 1905 1910 1915 1920 1925 1930 1935 1940 1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 1900 1895 Temperatuure (deg F)
70 69 68 67 66 65 64 63 62 61 60 Colorado Statewide Summer Temperature Average Colorado Statewide Average Summer (Jun-Aug) Temperature Temperature Average Temperature 1910 1915 1920 1925 1930 1935 1940 1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 1905 1900 1895 Temperature (deg F)
July 2005 Daily Temperatures July 2005 Daily Maximum and Mininum Temperatures 110 Colo Spr DIA Grand Jct Ft Collins 100 90 Temperature (deg F) 80 70 60 50 40 1 2 3 4 5 6 7 8 9 10111213141516171819202122232425262728293031 Day
Joe Wright Snotel
University Camp Snotel
Hoosier Pass Snotel
Upper San Juan Snotel
April 1 Snowpack
Water Year 2005 precipitation as a percent of the 1971-2000 average
Boulder 2005 Water Year 2005 Water Year 30 Year Averages-1971-2000 Max Year - 1995 Min Year - 1966 Period of Record Average - 1894-2002 2002 Water Year 35 30 Accumulated Precipitation (inches) 25 20 15 10 5 0 OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP Months
Cheesman 2005 Water Year 30 Year Averages-1971-2000 Max Year - 1970 Min Year - 2002 Period of Record Average - 1904-2002 25 2005 Water Year Accumulated Precipitaton (Inches) 20 15 10 5 0 OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP Months
Leroy 5SW 2005 Water Year 30 Year Averages-1971-2000 Max Year - 1995 Min Year - 1894 Period of Record Average - 1890-2002 2005 Water Year Accumulated 2002 Water Year Accumulated 30 25 Accumulated Precipitation (Inches) 20 15 10 5 0 OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP Months
25 20 15 10 5 Colorado Statewide Water Year Precipitation Totals Colorado Statewide Water Year (Oct-Sep) Precipitation from 1896-2005 1895 1995 1900 1905 1910 1915 1920 1925 1930 1935 1940 1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 2000 2005 Year Precipitation (inches)
South Platte Headquarters
South Platte River at Englewood
St. Vrain Creek below Longmont
South Platte River at Fort Morgan
Oct 1. 2005 140 120 100 80 60 40 20 0 Reservoir Storage Levels Colorado Statewide Reservoir Levels on October 1st for Years 1997-2004 and Oct 1, 2005 Oct 1. 1998 Oct 1. 1999 Oct 1. 2000 Oct 1. 2001 Oct 1. 2002 Oct 1. 2003 Oct 1. 2004 Oct 1. 1997 Percent of Average
Summary Snow blitz across southern Rockies. Near-average snowpack in the South Platte basin. Mild winter (12 th in a row). Beneficial April and early June precipitation. A hot and dry July. Below average growing season precipitation. A saving Denver-metro rain August 3-5 th. Overall Above average temperature, near to slightly below average precipitation. October 2005 Great moisture on the Plains!
1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 48-Month SPI Fraction of Colorado in Drought Based on 48 month SPI (1890 - September 2005) 1890 1892 1894 1896 1898 1900 1902 1904 1906 1908 1910 1912 1914 1916 1918 1920 1922 1924 1926 1928 1930 1932 1934 1936 1938 1940 1942 1944 1946 1948 1950 1952 1954 1956 1958 1960 1962 1964 1966 1968 1970 1972 1974 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 Year Fraction (in percent)
Temperature Nov-Jan 2006 From the Colorado Prediction Center http://www.cpc.ncep.noaa.gov/products/predictions/multi_season/13_seasonal_outlooks/color/churchill.html
Precipitation Nov-Jan 2006 From the Colorado Prediction Center http://www.cpc.ncep.noaa.gov/products/predictions/multi_season/13_seasonal_outlooks/color/churchill.html
Temperature Feb-Apr 2006 From the Colorado Prediction Center http://www.cpc.ncep.noaa.gov/products/predictions/multi_season/13_seasonal_outlooks/color/churchill.html
Precipitation Feb-Apr 2006 From the Colorado Prediction Center http://www.cpc.ncep.noaa.gov/products/predictions/multi_season/13_seasonal_outlooks/color/churchill.html
Temperature May-Jul 2006 From the Colorado Prediction Center http://www.cpc.ncep.noaa.gov/products/predictions/multi_season/13_seasonal_outlooks/color/churchill.html
Precipitation May-Jul 2006 From the Colorado Prediction Center http://www.cpc.ncep.noaa.gov/products/predictions/multi_season/13_seasonal_outlooks/color/churchill.html
And How About CoCoRaHS?
CoCoRaHS Colorado Statewide map for April 11, 2005
CoCoRaHS Colorado Statewide map for August 4, 2005
CoCoRaHS Colorado Statewide map for October 10, 2005
CoCoRaHS Colorado Statewide map for October 11, 2005
For more information visit the CoCoRaHS Web site http://www.cocorahs.org Support for this project provided by Informal Science Education Program, National Science Foundation and many local charter sponsors.
Colorado Climate Center Data and Power Point Presentations available for downloading http://ccc.atmos.colostate.edu click on Drought then click on Presentations