Green Water Supply Outlook, June 1, 2017

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		70%
Exceedance
Volume		50%
Exceedance
Volume		Percent
Average		30%
Exceedance
Volume		10%
Exceedance
Volume
Green
Daniel, Nr, Warren Bridge, At April-July395 410 430 176 445 465
June-July250 265 285 170 300 320
Pine Ck
Fremont Lk, Abv April-July136 143 148 151 152 161
June-July111 118 123 162 127 136
New Fork
Big Piney, Nr April-July600 620 670 189 710 730
June-July410 430 480 188 520 540
Green
Fontenelle Res, Fontenelle Nr April-July1540 1620 1680 232 1730 1820
June-July890 965 1030 217 1080 1170
Big Sandy
Farson, Nr April-July72 76 81 156 84 88
June-July46 50 55 162 58 62
Green
Green River, Wy, Nr April-July1580 1650 1710 234 1780 1860
June-July920 995 1050 219 1120 1200
Hams Fork
Frontier, Nr, Pole Ck, Blo April-July105 109 113 209 117 124
June-July34 38 42 162 46 53
Viva Naughton Res April-July150 155 161 218 165 173
June-July41 46 52 168 56 64
Blacks Fork
Robertson, Nr April-July102 107 114 128 119 125
June-July53 58 65 110 70 76
Ef Smiths Fork
Stateline Res, Robertson,nr April-July33 35 37 142 39 41
June-July17 18.5 21 118 23 25
Green
Flaming Gorge Res, Flaming Gorge Dam, At April-July1950 2060 2180 222 2260 2380
June-July1020 1130 1250 208 1330 1450


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-July12.6 13.2 13.9 60 14.5 15.5
June-July6.1 6.7 7.4 86 8 9
Steamboat Springs April-July183 192 200 77 210 230
June-July82 91 99 83 109 130
Elk
Milner, Nr April-July305 320 340 106 355 385
June-July100 116 136 86 150 180
Elkhead Ck
Long Gulch, Abv, Hayden, Nr April-July64 65 67 92 68 71
June-July5 5.4 7.5 72 8.9 12
Yampa
Maybell, Nr April-July695 730 770 82 800 865
June-July240 275 315 81 345 410
Little Snake
Slater, Nr April-July118 125 132 85 139 148
June-July33 40 47 71 54 63
Dixon, Nr April-July235 240 255 74 270 290
June-July71 79 92 68 108 127
Lily, Nr April-July245 255 270 78 285 305
June-July70 78 91 68 108 128
Yampa
Deerlodge Park April-July930 980 1030 83 1070 1170
June-July320 370 415 83 455 560
White
Meeker, Nr April-July192 198 205 73 215 230
June-July85 91 99 69 108 125
Watson, Nr April-July196 205 215 77 225 245
June-July87 97 106 76 115 135


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-July20 21 21 100 22 24
June-July5 5.7 6.1 68 6.8 9
Ashley Ck
Vernal, Nr April-July49 53 55 110 56 60
June-July17 21 23 96 24 28
West Fork Duchesne
Vat Diversion, Blo April-July32 33 34 183 36 37
June-July15 15.9 17 183 18.4 20
Duchesne
Tabiona, Nr April-July162 167 174 161 179 190
June-July87 92 99 165 104 115
Rock Ck
Upper Stillwater Res April-July102 107 111 150 114 122
June-July58 63 67 143 70 78
South Fork Rock Ck
Docs Div, Blo April-July10.4 11.2 11.5 158 11.9 12.8
June-July6.1 6.9 7.2 147 7.6 8.5
Rock Ck
Mountain Home, Nr April-July125 130 134 152 138 145
June-July70 75 79 141 83 90
Currant Ck
Currant Ck Res April-July31 32 33 165 34 37
June-July9.5 10.5 12 162 13.3 15.5
Strawberry
Solider Springs,nr April-July107 108 112 158 114 117
June-July22 23 27 113 29 32
Starvation Res, Duchesne, Nr April-July195 197 205 183 210 215
June-July50 52 61 161 64 70
Duchesne
Duchesne, Nr, Knight Div, Abv April-July285 295 300 155 310 325
June-July157 167 175 152 181 196
Lake Fork
Moon Lake Res, Mtn Home, Nr April-July88 91 95 144 100 104
June-July51 54 58 135 63 67
Yellowstone
Altonah, Nr April-July88 91 97 159 102 107
June-July53 56 62 151 67 72
Whiterocks
Whiterocks, Nr April-July61 65 70 130 74 79
June-July32 36 41 121 45 50
Uinta
Neola, Nr April-July101 105 112 151 118 124
June-July63 67 74 148 80 86
Duchesne
Myton April-July535 555 580 176 595 625
June-July240 260 285 165 300 330
Randlett, Nr April-July610 640 680 177 700 740
June-July280 310 350 167 370 410


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-July24 24 25 161 25 26
June-July3 3 3.5 103 3.7 4.5
Fish Ck
Scofield, Nr, Reservoir, Abv April-July35 36 37 123 38 41
June-July6 6.4 7.5 77 8.2 11.2
Price
Scofield Res, Scofield, Nr April-July52 54 57 139 60 63
June-July8 9.8 13 97 16 19
Green
Green River, Ut April-July3870 4020 4230 143 4370 4670
June-July1800 1950 2160 139 2300 2600
Huntington Ck
Electric Lake April-July21 21 22 165 23 25
June-July5 5.5 6.5 135 6.8 9.5
Power Plant, Blo April-July55 57 60 150 63 68
June-July23 25 28 141 31 36
Seeley Ck
Joes Vly Res, Orangeville, Nr April-July69 72 75 134 78 82
June-July30 33 36 113 39 43
Ferron Ck
Ferron, Nr April-July51 54 56 147 58 61
June-July23 26 28 133 30 33
Muddy Ck
Emery, Nr April-July23 24 25 126 26 28
June-July11 11.5 12.5 107 13.1 16

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 129.5 79 38 251.9 154 164.0 344.8
untitled Big Sandy
Big Sandy Res, Farson, Nr 38.4 131 100 34.0 116 29.4 38.3
Blacks Fork
Meeks Cabin 28.8 115 96 25.2 101 24.9 29.9
untitled Ef Smiths Fork
Stateline Res, Robertson,nr 14.1 125 102 11.9 106 11.3 13.9
untitled Green
Flaming Gorge Res, Flaming Gorge Dam, At 3202.9 104 85 3427.2 112 3071.5 3749.0
untitled Strawberry
Solider Springs,nr 927.5 130 84 828.7 116 716.0 1105.9
Starvation Res, Duchesne, Nr 141.0 91 85 163.9 106 154.8 165.3
untitled Rock Ck
Upper Stillwater Res 11.1 71 35 6.5 42 15.7 31.4
untitled Lake Fork
Moon Lake Res, Mtn Home, Nr 31.2 109 85 23.6 83 28.6 36.5
untitled Big Brush Ck
Red Fleet Res, Vernal, Nr 24.6 105 96 25.7 110 23.4 25.7
untitled Price
Scofield Res, Scofield, Nr 64.5 133 98 25.8 53 48.5 65.8
untitled Seeley Ck
Joes Vly Res, Orangeville, Nr 50.1 97 80 42.8 83 51.6 62.5
untitled Huntington Ck
Electric Lake 30.6 129 97 21.8 91 23.8 31.5
untitled
TOTAL 4694.2 108 82 4889.1 112 4363.6 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