New 1991-2020 Averages being used this year.
Green Water Supply Outlook, January 1, 2022

Green Water Supply Outlook, January 1, 2022

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

Contents

Green Summary




*Median of forecasts within each basin.


Upper Green Basin Conditions




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

Yampa/White Basin Conditions




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

Duchesne Basin Conditions




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

Lower Green Basin Conditions




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


Upper Green 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
Green
Daniel, Nr, Warren Bridge, At April-July148 195 240 94 295 340
Pine Ck
Fremont Lk, Abv April-July58 70 86 85 95 115
New Fork
Big Piney, Nr April-July145 210 265 75 325 430
Green
Fontenelle Reservoir, Fontenelle, Nr April-July310 535 650 88 775 970
Big Sandy
Farson, Nr April-July20 30 40 80 47 62
Green
Green River, Wy, Nr April-July300 525 650 88 785 1010
Hams Fork
Frontier, Nr, Pole Ck, Blo April-July25 30 43 83 60 70
Viva Naughton Reservoir April-July30 39 55 75 86 105
Blacks Fork
Robertson, Nr April-July56 65 90 102 102 120
Ef Smiths Fork
Stateline Reservoir, Robertson,nr April-July18.5 23 28 100 34 38
Green
Flaming Gorge Reservoir April-July420 650 840 87 1130 1420


Yampa/White 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
Yampa
Stagecoach Rsvr, Abv April-July19.5 23 27 100 31 38
Steamboat Springs April-July155 205 250 96 285 340
Elk
Milner, Nr April-July260 315 395 120 430 470
Elkhead Ck
Long Gulch, Abv, Hayden, Nr April-July55 70 90 127 110 130
Yampa
Maybell, Nr April-July620 800 985 107 1130 1330
Little Snake
Slater, Nr April-July105 125 170 110 200 220
Dixon, Nr April-July195 240 340 103 395 530
Lily, Nr April-July200 250 350 108 430 580
Yampa
Deerlodge Park April-July800 1010 1330 112 1570 1850
White
Meeker, Nr April-July175 200 240 92 280 400
Watson, Nr April-July170 200 245 91 295 430


Duchesne 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
Big Brush Ck
Vernal, Nr, Red Fleet Res, Abv April-July10 13.5 17 87 20 28
Ashley Ck
Vernal, Nr April-July21 30 40 87 49 70
West Fork Duchesne
Vat Diversion, Blo April-July12 16 20 118 27 35
Duchesne
Tabiona, Nr April-July70 83 110 107 130 155
Rock Ck
Upper Stillwater Reservoir April-July58 68 82 114 102 125
South Fork Rock Ck
Docs Div, Blo April-July4.5 5.5 7.5 103 10 12
Rock Ck
Mountain Home, Nr April-July65 75 96 110 120 145
Currant Ck
Currant Ck Reservoir April-July16 20 25 141 35 45
Strawberry
Strawberry Reservoir, Soldier Springs April-July29 38 60 100 82 105
Starvation Reservoir, Duchesne, Nr April-July65 85 125 133 160 210
Duchesne
Duchesne, Nr, Knight Div, Abv April-July140 170 205 109 250 290
Lake Fork
Moon Lake Reservoir, Mtn Home, Nr April-July45 55 67 105 83 105
Yellowstone
Altonah, Nr April-July45 58 68 113 82 102
Whiterocks
Whiterocks, Nr April-July34 47 56 110 65 90
Uinta
Neola, Nr April-July45 65 80 111 93 123
Duchesne
Myton April-July190 240 345 113 475 575
Randlett, Nr April-July200 255 385 110 525 650


Lower Green 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
White
Blo Tabbyune Ck, Soldier Summit, Nr April-July6 9.5 16 127 23 28
Fish Ck
Scofield, Nr, Reservoir, Abv April-July20 25 33 127 42 50
Price
Scofield Reservoir, Scofield, Nr April-July26 35 44 129 58 75
Green
Green River, Ut April-July1730 2230 2950 105 3630 4620
Huntington Ck
Electric Lake April-July10 13 17 150 20 25
Power Plant, Blo April-July35 43 52 130 62 72
Seeley Ck
Joes Vly Reservoir, Orangeville, Nr April-July36 46 54 106 67 80
Ferron Ck
Ferron, Nr April-July25 31 37 106 47 60
Muddy Ck
Emery, Nr April-July12 14.5 17.5 96 24 30

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).

Green 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 Green
Fontenelle Reservoir, Fontenelle, Nr 203.0 102 61 179.9 90 199.0 334.0
untitled Big Sandy
Big Sandy Reservoir, Nr Farson 6.1 38 16 8.0 50 16.1 38.3
Blacks Fork
Meeks Cabin 9.0 88 30 3.2 32 10.2 29.9
untitled Ef Smiths Fork
Stateline Reservoir, Robertson,nr 5.1 94 37 3.6 66 5.4 13.9
untitled Green
Flaming Gorge Reservoir 2899.9 93 77 3156.9 101 3110.9 3749.0
untitled Strawberry
Strawberry Reservoir, Soldier Springs 811.7 100 73 919.4 113 810.6 1105.9
Starvation Reservoir, Duchesne, Nr 125.3 94 76 134.8 101 133.2 165.3
untitled Rock Ck
Upper Stillwater Reservoir 28.7 259 91 9.3 84 11.1 31.4
untitled Lake Fork
Moon Lake Reservoir, Mtn Home, Nr 21.7 122 59 11.0 62 17.7 36.5
untitled Big Brush Ck
Red Fleet Reservoir, Vernal, Nr 9.9 58 39 15.4 90 17.2 25.7
untitled Price
Scofield Reservoir, Scofield, Nr 16.3 67 25 31.4 129 24.2 65.8
untitled Seeley Ck
Joes Vly Reservoir, Orangeville, Nr 21.2 56 34 38.0 101 37.7 62.5
untitled Huntington Ck
Electric Lake 11.4 63 36 19.7 109 18.1 31.5
untitled
TOTAL 4169.3 95 73 4530.7 103 4411.4 5689.6

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: Brenda Alcorn