Colorado s 2003 Moisture Outlook Nolan Doesken and Roger Pielke, Sr. Colorado Climate Center Prepared by Tara Green and Odie Bliss http://climate.atmos.colostate.edu
How we got into this drought!
Fort Collins Total Water Year Precipitation (Oct-Sep) 35 30 Precipitation (inches) 25 20 15 10 5 0 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 Month
Through 1999
Through 1999
Reservoir Storage Statewide Reservoir Levels for Colorado 140 120 Percent of Average 100 80 60 40 20 0 Oct 1. 1998 Oct 1. 1999 Oct 1. 2000 Oct 1. 2001 Oct 1. 2002 Feb 1. 2003 Date Provisional Data Provided by NRCS
Colorado Statewide Annual Temperatures through 2002 50 Colorado Average Annual Temperature (1895-2002) Temperature (degrees F) 48 46 44 42 40 1895 1905 1915 1925 1935 1945 1955 1965 1975 1985 1995 2005 Year From NOAA, National Climatic Data Center
Summer Temperatures Fort Collins, 1889-2002 Fort Collins Summer Average Temperature (June - August), 1889-2002 Summer Total 7 year running mean 74 Temperature (Deg. F) 72 70 68 66 64 62 60 58 1889 1899 1909 1919 1929 1939 1949 1959 1969 1979 1989 1999 Years
Where do we stand now?
Oct 2002 - Jan 2003 Precipitation as percent of average
Temperature - Water Year 2003 10 Departure from average, degree F 8 6 4 2 0-2 -4-6 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Eastern Plains Foothills Mountains Western Valleys
Water Year 2003 UPPER SAN JUAN SNOTEL
Water Year 2003 HOOSIER PASS SNOTEL
Water Year 2003 JOE WRIGHT SNOTEL
Grand Lake 1 NW 2003 Water Year (through October '02-January '03) 30 Year Averages-1971-2000 Max Year - 1984 Min Year - 2002 Period of Record Average - 1941-2002 2003 Water Year Accumulated 35 Accumulated Precipitation (Inches) 30 25 20 15 10 5 0 OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP Months
Akron 4E 2003 Water Year (through October '02-January'03) 35 30 Year Averages-1971-2000 Max Year - 1915 Min Year - 1966 Period of Record Average - 1906-2002 2003 Water Year Accumulated Accumulated Precipitation (Inches) 30 25 20 15 10 5 0 OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP Months
What May Be Ahead in 2003
Precipitation 4.0 3.5 Monthly Average Precipitation for Selected Sites in the South Platte Basin Hoosier Pass Denver Stapleton Sterling Precipitation (inches) 3.0 2.5 2.0 1.5 1.0 0.5 0.0 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Month
Monthly Average Precipitation for 1971-2000 3.5 3.0 Precipitation (inches) 2.5 2.0 1.5 1.0 0.5 0.0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month Lamar Cheyenne Wells Walsh Center Fruita
A few storms contribute a large fraction of annual precipitation while many small events contribute a small fraction. Precipitation
Greeley Daily Accumulated Precipitation 20 Accumulated Daily 1999 2000 2001 2002 Precipitation (inches) 15 10 5 0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Day
What Happens Next We have never experienced 2 consecutive extreme statewide drought years. Past multi-year drought, characterized by one extreme year preceded and followed by other dry year. Entire State rarely all recovers quickly and at the same time. Hope for the best, plan for the worst!!
Our Path For 2003 Precipitation (inches) 16 14 12 10 8 6 4 2 0 Greeley, Colorado Monthly Accumulated Precipitation for Water Year 2003 vs. 30-year Averages (1971-2000). 30-yr Acc WY2003 Acc Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Month
Positive Indicators Late winter snows Cool spring Multi-day precipitation Low intensity rainfall Light winds High humidity Abundant cloud cover
Negative Indicators Little late winter snow Missed opportunities Warm spring Brief, sporadic precipitation High intensity rainfall Frequent, strong winds Low humidity Abundant sunshine
Current Indicators El Niño still present Unfavorable Pacific decadal oscillation Missed opportunities February not a good indicator Wet often follows dry Most extreme dry periods last one year (Exceptions: SE CO)
Temperature March-May May 2003 From the Colorado Prediction Center http://www.cpc.ncep.noaa.gov/products/predictions/multi_season/13_seasonal_outlooks/color/churchill.html
Precipitation March-May May 2003 From the Colorado Prediction Center http://www.cpc.ncep.noaa.gov/products/predictions/multi_season/13_seasonal_outlooks/color/churchill.html
Temperature June-Aug 2003 From the Colorado Prediction Center http://www.cpc.ncep.noaa.gov/products/predictions/multi_season/13_seasonal_outlooks/color/churchill.html
Precipitation June-Aug 2003 From the Colorado Prediction Center http://www.cpc.ncep.noaa.gov/products/predictions/multi_season/13_seasonal_outlooks/color/churchill.html
Breaking This Drought A wet spring is essential to begin that process. Will Be Tough
COAGMET Weather Data for Agriculture Automated weather stations with daily and hourly readings of: Temperature Humidity Wind Precipitation Solar energy Evapotranspiration http://www.coagmet.com
Colorado Climate Magazine Good bedtime reading about the climate of Colorado -- recent and historic $15/year subscription pays printing and mailing costs
CoCo RaHS YOU CAN HELP! http://www.cocorahs.com
Colorado Climate Center Colorado State University Data and Power Point Presentations available for downloading http://climate.atmos.colostate.edu click on Drought then click on Presentations