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
Precipitation (inches)
30
25
20
15
10
5
0
1890
1900
1910
1920
1930
1940
1950
Month
1960
1970
1980
1990
2000
Through 1999
Through 1999
Reservoir Storage
Statewide Reservoir Levels for Colorado
140
Percent of Average
120
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
Colorado Average Annual Temperature
(1895 - 2002)
Temperature (degrees F)
50
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
Temperature (Deg. F)
74
72
70
68
66
64
62
60
58
99
19
89
19
79
19
69
19
59
19
49
19
39
19
29
19
19
19
09
19
99
18
89
18
Years
Where do we stand now?
Oct 2002 - Jan 2003 Precipitation as
percent of average
Temperature - Water Year 2003
Departure from average, degree F
10
8
6
4
2
0
-2
-4
-6
Oct
Nov
Dec
Jan
Eastern Plains
Feb
Mar
Foothills
Apr
May
Mountains
Jun
Jul
Aug
Western Valleys
Sep
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
Min Year - 2002
2003 Water Year Accumulated
Max Year - 1984
Period of Record Average - 1941 - 2002
30
25
20
15
10
5
Months
SE
P
UG
A
JU
L
JU
N
Y
M
A
PR
A
R
M
A
FE
B
JA
N
EC
D
O
V
N
T
0
O
C
Accumulated Precipitation
(Inches)
35
Akron 4E
2003 Water Year
(through October '02-January'03)
30 Year Averages-1971-2000
Min Year - 1966
2003 Water Year Accumulated
Max Year - 1915
Period of Record Average - 1906 - 2002
30
25
20
15
10
5
Months
SE
P
UG
A
JU
L
JU
N
Y
M
A
PR
A
R
M
A
FE
B
JA
N
EC
D
O
V
N
T
0
O
C
Accumulated Precipitation (Inches)
35
What May Be Ahead in 2003
Precipitation
Monthly Average Precipitation for Selected Sites
in the South Platte Basin
4.0
Hoosier Pass
Denver Stapleton
Sterling
Precipitation (inches)
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
Oct
Nov
Dec
Jan
Feb
Mar
Apr
Month
May
Jun
Jul
Aug
Sep
Monthly Average Precipitation for
1971-2000
3.5
Precipitation (inches)
3.0
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
Precipitation

A few storms
contribute a large
fraction of annual
precipitation
while many small
events contribute
a small fraction.
Greeley Daily Accumulated Precipitation
Accumulated Daily
1999
2000
2001
2002
Precipitation (inches)
20
15
10
5
0
Jan
Feb
Mar
Apr
May
Jun
Jul
Day
Aug
Sep
Oct
Nov
Dec
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
Greeley, Colorado
Monthly Accumulated Precipitation for Water Year 2003
vs. 30-year Averages (1971-2000).
16
30-yr Acc
Precipitation (inches)
14
WY2003 Acc
12
10
8
6
4
2
0
Oct
Nov
Dec
Jan
Feb
Mar
Apr
Month
May
Jun
Jul
Aug
Sep
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 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 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
Will Be Tough

A wet spring is
essential to begin
that process.
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”