New 1991-2020 Averages being used this year.
Upper Colorado Water Supply Outlook, April 1, 2022

Upper Colorado Water Supply Outlook, April 1, 2022

Note: This publication is scheduled for revision. If you have feedback on content, format, or publication frequency, please contact us.
Prepared by Cody Moser, Ashley Nielson
NOAA, National Weather Service
Colorado Basin River Forecast Center
Salt Lake City, Utah
www.cbrfc.noaa.gov

Contents

Upper Colorado Summary




*Median of forecasts within each basin.


Upper Colorado Mainstem Basin Conditions




Snow Water Equivalent in Percent of Median.
* Percent usable capacity, not percent average contents.
Click for multi-month Graph.

Gunnison Basin Conditions




Snow Water Equivalent in Percent of Median.
* Percent usable capacity, not percent average contents.
Click for multi-month Graph.

Dolores Basin Conditions




Snow Water Equivalent in Percent of Median.
* Percent usable capacity, not percent average contents.
Click for multi-month Graph.


Upper Colorado Mainstem Specific Site Forecasts (kaf)

Click site name for graph.
Forecast
Period		90%
Exceedance
Volume		70%
Exceedance
Volume		50%
Exceedance
Volume		Percent
Average		30%
Exceedance
Volume		10%
Exceedance
Volume
Colorado
Lake Granby, Granby, Nr April-July160 180 195 87 220 250
Willow Ck
Willow Ck Reservoir, Granby, Nr April-July33 40 48 96 55 65
Fraser
Winter Park April-July13 15 16.5 89 18 20
Williams Fork
Williams Fork Reservoir, Parshall April-July54 65 75 78 80 86
Muddy Ck
Wolford Mountain Reservoir April-July20 25 30 58 38 48
Blue
Dillon Reservoir April-July105 120 135 81 150 175
Green Mtn Reservoir April-July175 205 230 82 255 285
Colorado
Kremmling, Nr April-July550 650 730 84 800 900
Eagle
Gypsum, Blo April-July205 240 275 82 305 345
Colorado
Dotsero, Nr April-July900 1030 1150 82 1270 1400
Frying Pan
Ruedi Reservoir, Basalt, Nr April-July90 110 125 93 135 150
Roaring Fork
Glenwood Springs April-July480 540 590 90 650 740
Colorado
Glenwood Springs, Blo April-July1400 1620 1780 86 1950 2200
Cameo, Nr April-July1550 1780 1940 85 2150 2450
Cisco, Nr April-July2700 3050 3350 82 3750 4500
Lake Powell, Glen Cyn Dam, At April-July3100 3600 4100 64 4900 6500


Gunnison Specific Site Forecasts (kaf)

Click site name for graph.
Forecast
Period		90%
Exceedance
Volume		70%
Exceedance
Volume		50%
Exceedance
Volume		Percent
Average		30%
Exceedance
Volume		10%
Exceedance
Volume
Taylor
Taylor Park Reservoir April-July79 89 96 102 103 120
Almont April-July120 134 145 99 154 177
East
Almont April-July140 160 176 99 189 220
Gunnison
Gunnison, Nr April-July270 305 330 94 360 425
Tomichi Ck
Gunnison April-July32 41 47 70 56 70
Lake Fork
Gateview April-July72 80 89 75 103 130
Gunnison
Blue Mesa Reservoir April-July440 490 530 83 600 745
Morrow Point Reservoir April-July470 525 565 82 635 800
Crystal Reservoir April-July510 575 625 81 700 890
Muddy Ck
Paonia Reservoir, Bardine, Nr April-July52 63 75 93 85 96
Nf Gunnison
Somerset, Nr April-July185 210 235 89 255 290
Surface Ck
Cedaredge April-July10.5 12.9 14.8 101 16.9 20
Uncompahgre
Ridgway Reservoir April-July55 65 72 78 79 98
Colona April-July63 77 85 71 95 131
Delta April-July27 45 58 61 70 105
Gunnison
Grand Junction, Nr April-July875 1000 1100 83 1220 1520


Dolores Specific Site Forecasts (kaf)

Click site name for graph.
Forecast
Period		90%
Exceedance
Volume		70%
Exceedance
Volume		50%
Exceedance
Volume		Percent
Average		30%
Exceedance
Volume		10%
Exceedance
Volume
Dolores
Dolores April-July96 118 138 64 167 200
Mcphee Reservoir April-July106 128 152 60 188 230
San Miguel
Placerville, Nr April-July53 63 73 63 83 108
Dolores
Cisco, Nr April-July165 200 240 48 280 350

Differences between the full period forecasts and the residual forecasts may not exactly equal the actual observed volumes due to rounding conventions (see Definitions section).

Upper Colorado End of Month Reservoir Contents (kaf)

EOM
Contents		Percent
EOM
Average		Percent
Usable
Capacity		Last Year
EOM		Last Year
%Average		EOM
Average		Usable
Capacity
untitled Colorado
Lake Granby, Granby, Nr 301.8 92 62 355.3 108 327.9 490.3
untitled Willow Ck
Willow Ck Reservoir, Granby, Nr 9.1 108 100 7.0 83 8.4 9.1
untitled Williams Fork
Williams Fork Reservoir, Parshall 59.1 89 61 64.7 98 66.2 96.9
untitled Muddy Ck
Wolford Mountain Reservoir 30.2 68 46 52.8 118 44.7 66.0
untitled Blue
Dillon Reservoir 196.3 91 77 199.3 92 216.3 254.0
Green Mtn Reservoir 53.9 82 37 66.8 101 66.0 146.9
untitled Homestake Ck
Homestake Reservoir 14.4 57 34 11.8 46 25.4 43.0
untitled Frying Pan
Ruedi Reservoir, Basalt, Nr 55.2 87 54 58.4 92 63.7 102.0
untitled Plateau Ck
Vega Reservoir, Collbran, Nr 6.3 44 19 6.1 43 14.2 32.9
untitled Taylor
Taylor Park Reservoir 57.3 86 54 62.1 93 66.4 106.2
untitled Gunnison
Blue Mesa Reservoir 239.1 49 29 399.0 82 488.3 827.9
Morrow Point Reservoir 109.0 99 93 104.5 95 109.7 117.0
Crystal Reservoir 16.8 105 96 15.7 98 16.0 17.5
untitled Muddy Ck
Paonia Reservoir, Bardine, Nr 4.3 139 26 5.4 174 3.1 16.7
untitled Uncompahgre
Ridgway Reservoir 67.1 98 81 55.2 81 68.3 83.0
untitled Dolores
Mcphee Reservoir 177.1 66 46 169.4 63 269.9 381.1
untitled
TOTAL 1397.0 75 50 1633.3 88 1854.5 2790.6
Colorado
Lake Powell 5812.4 42 24 8843.8 63 13994.9 24322.0
untitled
TOTAL 5812.4 42 24 8843.8 63 13994.9 24322.0

Precipitation Maps




Definitions

10% exceedance forecast: Given the current hydrometeorological conditions, i.e current snowpack, soil moisture and streamflow, the volume that has a 10% chance of being exceeded. Previously referred to as "Reasonable Maximum Forecast".

50% exceedance forecast: Given the current hydrometeorological conditions, i.e current snowpack, soil moisture and streamflow, the volume that has a 50% chance of being exceeded. Previously referred to as "Most Probable Forecast".

90% exceedance forecast: Given the current hydrometeorological conditions, i.e current snowpack, soil moisture and streamflow, the volume that has a 90% chance of being exceeded. Previously referred to as "Reasonable Minimum Forecast".

Acre-Foot (af): The volume equal to one acre covered one foot deep (43,560 cubic feet). See kaf below.

Average: The arithmetic mean. The sum of the values divided by the number of values. Values from 1991-2020 are used for this publication.

Categories: Much Above Average=Greater than 130%, Above Average=111-130%, Near Average=90-110%, Below Average=70-89%, Much Below Average=Less than 70%.

CBRFC: Colorado Basin River Forecast Center.

Forecast Period: The period from April 1 through July 31, unless otherwise noted.

kaf: Thousand Acre-Feet. See Acre-Foot above.

Inflow: The volume of water that flows into a reservoir or lake.

Median: The middle value of an ordered set of values. Half of the values are higher and half of the values are lower. When the set contains an even number of values the median is the average of the two middle numbers.

NOAA: National Oceanic and Atomospheric Administration.

NWS: National Weather Service.

Rounding Conventions:
RangeRound to
0-1.990.01
2.0-19.90.1
20-1991.0
200-9995.0
1000+3 significant digits


Streamflow: The volume of water that flows past a specific stream site.

Water Year: The 12-month period, October 1 through September 30. The water year is designated by the calendar year in which it ends. Thus, the year ending September 30, 2008, is called the "2008 water year."


Additional Information

Water supply forecasts take into consideration present hydrometeorological conditions and use average basin temperatures and precipitation for the forecast period. As the forecast season progresses, a greater portion of the future hydrologic and climatic uncertainty becomes known and monthly forecasts become more accurate. For more information on the tools we use, consult Water Supply Forecasting Tools.

Volume forecasts represent adjusted flows; that is, observed flows with upstream water use taken into account. Adjusted flows will closely approximate natural or unimpaired flows. However, not all upstream diversions or impoundments are measured or quantifiable. For specific adjustments used with each forecast point, consult the Guide to Water Supply Forecasting.

The Water Supply Outlook is issued monthly January through May by the Colorado Basin River Forecast Center. It represents a coordinated effort between the National Weather Service, Natural Resources Conservation Service, Bureau of Reclamation, U.S. Geological Survey and local water district managers.

Note: Data used in this report are provisional and are subject to revision.

For more information, or to be included on the mailing list, please contact:

Colorado Basin River Forecast Center
2242 W North Temple
Salt Lake City, UT 84116
(801) 524-5130
www.cbrfc.noaa.gov


Hydrologist: Cody Moser, Ashley Nielson