Green Water Supply Outlook, February 1, 2015

Note: This publication is scheduled for revision. If you have feedback on content, format, or publication frequency, please contact us.
Prepared by Ashley Nielson
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		50%
Exceedance
Volume		Percent
Average		10%
Exceedance
Volume
Green
Daniel, Nr, Warren Bridge, At April-July190 260 106 340
Pine Ck
Fremont Lk, Abv April-July70 95 97 120
New Fork
Big Piney, Nr April-July205 320 90 470
Green
Fontenelle Res, Fontenelle Nr April-July520 725 100 1060
Big Sandy
Farson, Nr April-July26 40 77 64
Green
Green River, Wy, Nr April-July510 730 100 1100
Hams Fork
Frontier, Nr, Pole Ck, Blo April-July31 48 89 78
Viva Naughton Res April-July45 65 88 120
Blacks Fork
Robertson, Nr April-July44 66 74 103
Ef Smiths Fork
Stateline Res, Robertson,nr April-July15 20 77 29
Green
Flaming Gorge Res, Flaming Gorge Dam, At April-July600 875 89 1520


Yampa/White Specific Site Forecasts (kaf)

Click site name for graph.
Forecast
Period		90%
Exceedance
Volume		50%
Exceedance
Volume		Percent
Average		10%
Exceedance
Volume
Yampa
Stagecoach Rsvr, Abv April-July16.7 23 100 31
Steamboat Springs April-July150 230 88 315
Elk
Milner, Nr April-July200 280 88 370
Elkhead Ck
Long Gulch, Abv, Hayden, Nr April-July23 49 67 67
Yampa
Maybell, Nr April-July480 740 79 1000
Little Snake
Slater, Nr April-July79 115 74 162
Dixon, Nr April-July128 205 59 330
Lily, Nr April-July122 210 61 340
Yampa
Deerlodge Park April-July605 945 76 1300
White
Meeker, Nr April-July180 240 86 325
Watson, Nr April-July180 250 89 350


Duchesne Specific Site Forecasts (kaf)

Click site name for graph.
Forecast
Period		90%
Exceedance
Volume		50%
Exceedance
Volume		Percent
Average		10%
Exceedance
Volume
Big Brush Ck
Vernal, Nr, Red Fleet Res, Abv April-July6.5 12.8 61 22
Ashley Ck
Vernal, Nr April-July16.2 30 60 56
West Fork Duchesne
Vat Diversion, Blo April-July7.5 12.4 67 20
Duchesne
Tabiona, Nr April-July60 83 77 115
Rock Ck
Upper Stillwater Res April-July47 62 84 93
South Fork Rock Ck
Docs Div, Blo April-July3.4 5.2 71 8.4
Rock Ck
Mountain Home, Nr April-July57 74 84 111
Currant Ck
Currant Ck Res April-July7 12 60 21
Strawberry
Solider Springs,nr April-July23 40 56 80
Starvation Res, Duchesne, Nr April-July43 72 64 128
Duchesne
Duchesne, Nr, Knight Div, Abv April-July118 155 80 215
Lake Fork
Moon Lake Res, Mtn Home, Nr April-July38 53 80 77
Yellowstone
Altonah, Nr April-July39 51 84 71
Whiterocks
Whiterocks, Nr April-July23 36 67 61
Uinta
Neola, Nr April-July32 55 74 83
Duchesne
Myton April-July140 215 65 380
Randlett, Nr April-July150 230 60 430


Lower Green Specific Site Forecasts (kaf)

Click site name for graph.
Forecast
Period		90%
Exceedance
Volume		50%
Exceedance
Volume		Percent
Average		10%
Exceedance
Volume
White
Blo Tabbyune Ck, Soldier Summit, Nr April-July5.2 10.7 69 18
Fish Ck
Scofield, Nr, Reservoir, Abv April-July14.3 21 70 35
Price
Scofield Res, Scofield, Nr April-July18 28 68 48
Green
Green River, Ut April-July1600 2270 77 3500
Huntington Ck
Electric Lake April-July4.5 9 68 16
Power Plant, Blo April-July19 28 70 47
Seeley Ck
Joes Vly Res, Orangeville, Nr April-July32 45 80 75
Ferron Ck
Ferron, Nr April-July24 34 89 54
Muddy Ck
Emery, Nr April-July12.4 18 90 28

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 Res, Fontenelle Nr 232.7 155 67 162.7 108 150.1 344.8
untitled Big Sandy
Big Sandy Res, Farson, Nr 21.5 130 56 9.2 56 16.6 38.3
Blacks Fork
Meeks Cabin 22.6 196 76 13.1 114 11.5 29.9
untitled Ef Smiths Fork
Stateline Res, Robertson,nr 8.5 153 62 6.8 122 5.6 13.9
untitled Green
Flaming Gorge Res, Flaming Gorge Dam, At 3232.9 106 86 2847.2 93 3050.5 3749.0
untitled Strawberry
Solider Springs,nr 837.6 127 76 830.2 126 659.9 1105.9
Starvation Res, Duchesne, Nr 146.8 106 89 148.0 107 138.8 165.3
untitled Rock Ck
Upper Stillwater Res 14.2 164 45 9.9 115 8.6 31.4
untitled Lake Fork
Moon Lake Res, Mtn Home, Nr 30.6 125 84 23.2 95 24.4 36.5
untitled Big Brush Ck
Red Fleet Res, Vernal, Nr 11.3 63 44 10.7 59 18.0 25.7
untitled Price
Scofield Res, Scofield, Nr 12.3 41 19 14.5 48 29.9 65.8
untitled Seeley Ck
Joes Vly Res, Orangeville, Nr 40.7 104 65 30.1 77 39.3 62.5
untitled Huntington Ck
Electric Lake 18.8 98 60 17.0 89 19.2 31.5
untitled
TOTAL 4630.6 111 81 4122.6 99 4172.4 5700.4

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 1981-2010 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: Ashley Nielson