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Wyoming Basin Outlook Report for
LOWER GREEN RIVER BASIN as of March 1, 2012

Snow SWE in the Green River Basin above Flaming Gorge is 90% of average. SWE in the Hams Fork Basin is 82% of average. Blacks Fork Basin SWE is currently 81% of average. In the Henrys Fork drainage SWE is 134%. For more information see Basin Summary of Snow Course Data at the beginning of this report. Precipitation Precipitation for the 3 reporting stations during last month was at 74% of average or 89% of last year. Precipitation ranged from 60- 95% of average for the month. The basin year-to-date precipitation is currently 79% of average (68% of last year). Year-to-date percentages range from 75-87% of average. Reservoirs Fontenelle Reservoir is currently storing 125,300 ac-ft; this is 80% of average (80% of last year). Flaming Gorge is currently storing 3,293,000 ac-ft; this is 113% of average (106% of last year). Viva Naughton is currently storing 28,600 ac-ft, 98% of average or 67% of capacity. Detailed reservoir data is shown on the following page and on the reservoir storage summary at the beginning of this report. Streamflow The 50% exceedance forecasts for the April through July runoff period in the Lower Green River Basin are forecast to be below average. The Green River near Green River is forecast to yield about 745,000 ac-ft (85% of average). The Blacks Fork near Robertson is forecast to yield 74,000 ac-ft (78% of average). East Fork of Smiths Fork near Robertson is forecast to yield 22,000 ac-ft (76% of average). Hams Fork below Pole Creek near Frontier is forecast to be 45,000 ac-ft (69% of average). The Hams Fork Inflow to Viva Naughton Reservoir is forecast to be 59,000 ac-ft (66% of average). The Flaming Gorge Reservoir inflow will be about 945,000 ac-ft (79% of average). See the following table for more detailed information on projected runoff.

Streamflow Forecasts

LOWER GREEN RIVER BASIN
Streamflow Forecasts - March 1, 2012

 <==== Drier === Future Conditions === Wetter ====> 
Forecast Pt============ Chance of Exceeding * =========== 
   Forecast90%70%50% (Most Prob)30%10%30 Yr Avg
   Period(1000AF)(1000AF)(1000AF)(% AVG.)(1000AF)(1000AF)(1000AF)

Green R nr Green River, WY (2)
APR-JUL 480       640       745       85       850       1010       875      
Blacks Fk nr Robertson
APR-JUL 49       63       74       78       86       104       95      
EF of Smiths Fork nr Robertson (2)
APR-JUL 13.4       18.3       22       76       26       33       29      
Hams Fk bl Pole Ck nr Frontier
APR-JUL 28       38       45       69       53       66       65      
Viva Naughton Reservoir Inflow (2)
APR-JUL 30       45       59       66       73       94       89      
Flaming Gorge Reservoir Inflow (2)
APR-JUL 585       790       945       79       1120       1390       1190      

    * 90%, 70%, 30%, and 10% chances of exceeding are the probabilities that the
       actual flow will exceed the volumes in the table.

    (1) - The values listed under the 10% and 90% Change of Exceeding are
            actually 5% and 95% exceedance levels.
    (2) - The value is natural flow - actual flow may be affected by upstream
            water management.



Reservoir Storage

LOWER GREEN RIVER BASIN
Reservoir Storage (1000AF) End of February

 Usable************* Usable Storage *************
Reservoir Capacity This Year Last Year Average

FONTENELLE 344.8      125.3         157.6          156.1        
FLAMING GORGE 3749.0      3293.0         3104.0          2919.0        
VIVA NAUGHTON RES 42.4      28.6         29.9          29.1        



Watershed Snowpack Analysis

LOWER GREEN RIVER BASIN
Watershed Snowpack Analysis - March 1, 2012

 Number ofThis Year as Percent of
Watershed Data Sites Last Year Normal

HAMS FORK RIVER 4               68               82              
BLACKS FORK 4               73               81              
HENRYS FORK 2               116               133              
GREEN above Flaming Gorge 24               83               90              

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or Write:
D. Lee Hackleman, Water Supply Specialist
Natural Resources Conservation Service
100 East B Street
Casper, WY 82601
(307) 261-6481

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