Flood Potential Outlook
Issued by NWS Reno, NV

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WATER SUPPLY OUTLOOK
NATIONAL WEATHER SERVICE RENO NV
420 PM PST MON JAN 11 2016

...WATER SUPPLY OUTLOOK FOR NEVADA AND EASTERN CALIFORNIA AS OF
JAN 11 2016...

ISSUED JOINTLY BY THE NATIONAL WEATHER SERVICE AND NATURAL RESOURCES
CONSERVATION SERVICE...

1/SUMMARY...WATER SUPPLY OUTLOOK...

PRECIPITATION HAS BEEN ABOVE TO WELL ABOVE NORMAL FOR MUCH OF NEVADA
AND EASTERN CALIFORNIA SINCE THE BEGINNING OF THE WATER YEAR ON
OCTOBER 1, 2015. AREAS WITH THE HIGHEST WATER YEAR TO DATE
PRECIPITATION ARE EASTERN AND NORTH EASTERN NEVADA.

THE MOUNTAIN SNOWPACK GOT OFF TO AN EARLY START AND COOL
TEMPERATURES COMBINED WITH FREQUENT MODERATE STORMS HAVE CONTINUED
TO BUILD AN EXCELLENT EARLY SEASON SNOWPACK.  THIS IS AN ENCOURAGING
START AFTER FOUR DRY WINTERS, BUT WITH SEVERAL MORE MONTHS OF THE
SNOW ACCUMULATION SEASON REMAINING, A WIDE VARIETY OF OUTCOMES IS
STILL POSSIBLE.  WHILE THE CURRENT SNOWPACK ALREADY EXCEEDS LAST
YEAR`S PEAK IN EACH BASIN AND 2014 IN MANY, 2013 HAD A SIMILARLY
STRONG EARLY SNOWPACK ONLY TO DRY OUT LATER IN THE WINTER.

AFTER FOUR YEARS OF BELOW AVERAGE SNOWPACKS AND LOW STREAMFLOWS,
RESERVOIR STORAGE AND GENERAL WATER SUPPLY CONDITIONS ARE VERY POOR.
AN AVERAGE TO ABOVE AVERAGE YEAR WOULD BE GREATLY BENEFICIAL TO
WATER SUPPLY CONDITIONS, BUT IT WILL TAKE AN EXCEPTIONAL YEAR, OR
MORE LIKELY, MORE THAN ONE YEAR TO RETURN THE AREA TO PRE-DROUGHT
CONDITIONS.

2/SNOWPACK...

SNOWPACK AS OF JANUARY 8TH RANGE FROM NEAR AVERAGE AT 108% ON THE
TRUCKEE BASIN TO A HIGH OF 178% ON THE LOWER HUMBOLDT.  ALL BASINS
IN NORTHERN AND EASTERN NEVADA ARE MUCH ABOVE AVERAGE.

AS OF JANUARY 7TH TWO SNOTEL SITES IN NEVADA HAD THEIR SECOND
HIGHEST SNOW WATER EQUIVALENT (SWE) TO DATE FOR THE PERIOD OF
RECORD.  THESE SITES ARE DIAMOND PEAK NEAR EUREKA AND BIG BEND IN
THE OWYHEE.

ON AVERAGE PEAK BASIN SNOWPACK OCCURS BETWEEN MID-MARCH AND EARLY
APRIL.  CURRENTLY THE TAHOE, TRUCKEE, CARSON AND WALKER BASINS HAVE
NEAR 50% OF THEIR AVERAGE PEAK SNOWPACK, WHILE BASINS TO THE NORTH
AND EAST HAVE NEAR 70% OF AVERAGE BASIN PEAK CONDITIONS.  A
CONTINUATION OF COOL TEMPERATURES AND FREQUENT STORMS IS NEEDED TO
ATTAIN OR EXCEED AVERAGE SNOWPACK CONDITIONS NECESSARY TO PRODUCE
NEAR NORMAL STREAMFLOW RUNOFF.

                                 JAN 1 2016
BASIN                    PERCENT OF MEDIAN
LAKE TAHOE ........................   154
TRUCKEE RIVER .....................   115
CARSON RIVER ......................   149
WALKER RIVER ......................   140
NORTHERN GREAT ....................   193
UPPER HUMBOLDT RIVER ..............   192
LOWER HUMBOLDT RIVER ..............   190
CLOVER VALLEY & FRANKLIN RIVER ....   184
SNAKE RIVER .......................   179
OWYHEE RIVER ......................   203
EASTERN NEVADA ....................   164
LOWER COLORADO RIVER ..............   NA

3/PRECIPITATION...

CURRENT WATER YEAR TO DATE PRECIPITATION AS OF JANUARY 8TH IS NEAR,
TO MUCH ABOVE NORMAL THROUGHOUT NEVADA.  BASINS DRAINING TO THE EAST
SLOPE OF THE SIERRA ARE NEAR TO SLIGHTLY ABOVE AVERAGE AND
CONDITIONS GET PROGRESSIVELY WETTER TO THE EAST, WITH THE FAR EASTERN
NEVADA AREA AT 181%.  WHILE EACH MONTH OF THE WATER YEAR SO FAR
PRODUCED NEAR TO ABOVE AVERAGE PRECIPITATION THROUGH THE REGION,
DECEMBER WAS THE WETTEST.

AS OF JANUARY 7TH POLE CREEK SNOTEL IN NORTHEASTERN NEVADA HAS THE
HIGHEST, WHILE DIAMOND PEAK NEAR EUREKA HAS THE SECOND HIGHEST WATER
YEAR TO DATE PRECIPITATION FOR THE PERIOD OF RECORD.

                                                  WATER YEAR 2016
                                    DEC 2015    /THROUGH 12/31/2016/
BASIN                              PCT OF AVE        PCT OF AVE
LAKE TAHOE .........................   151 ...........   121
TRUCKEE RIVER ......................   118 ...........   106
CARSON RIVER .......................   112 ...........   117
WALKER RIVER .......................   123 ...........   121
NORTHERN GREAT .....................   179 ...........   134
UPPER HUMBOLDT RIVER ...............   185 ...........   156
LOWER HUMBOLDT RIVER ...............   162 ...........   145
CLOVER VALLEY AND FRANKLIN RIVER ...   196 ...........   157
SNAKE RIVER ........................   172 ...........   158
OWYHEE RIVER .......................   148 ...........   144
EASTERN NEVADA .....................   202 ...........   180
LOWER COLORADO RIVER ...............   NA  ...........   NA

4/RESERVOIRS...

AFTER FOUR YEARS OF LOW SNOWPACK AND RUNOFF, RESERVOIR STORAGE IN
THE AREA IS EXTREMELY LOW.  MOST AREAS HAVE SIMILAR TO, OR SOMEWHAT
LESS, STORAGE AS THIS TIME LAST YEAR.  AS OF THE END OF DECEMBER,
LAKE TAHOE WAS 1.4 FEET OR 170,000 ACRE-FEET BELOW THE NATURAL RIM
AND ANOTHER SIX FEET BELOW FULL. BOCA AND LAHONTAN RESERVOIRS ARE AT
THEIR SECOND LOWEST END OF DECEMBER LEVELS RECORDED.  STAMPEDE AND
LAKE MEAD ARE AT THE LOWEST LEVELS SINCE THEY STARTED TO FILL.
CURRENT STREAMFLOW FORECASTS ARE ENCOURAGING, INDICATING THAT THIS
YEAR MAY PROVIDE SIGNIFICANT FLOWS TO START REFILLING THE SYSTEM.

BASIN                        PERCENT OF CAPACITY   PERCENT OF AVERAGE
LAKE TAHOE ........................   0 ................   0
TRUCKEE RIVER .....................  19 ................  33
CARSON RIVER ......................   4 ................  10
WALKER RIVER ......................  15 ................  43
LOWER HUMBOLDT RIVER ..............   5 ................  15
OWYHEE RIVER ......................  15 ................  32
LOWER COLORADO RIVER ..............  42 ................  53

5/STREAMFLOW...

STREAMFLOW FORECASTS THROUGH JULY FOR ALL OF NEVADA AND EASTERN
CALIFORNIA AS OF JANUARY 1ST ARE FORECAST TO BE BELOW TO MUCH ABOVE
AVERAGE. WATER SUPPLY CONDITIONS ARE FORECAST TO BE MUCH HIGHER
THAN LAST YEAR, BUT WITH VERY SIGNIFICANT VARIATION FROM AREA TO
AREA AS WELL AS FROM NRCS AND NWS FORECAST METHODOLOGIES.  WHILE
CURRENT PRECIPITATION AND SNOWPACK MEASUREMENTS INDICATE AVERAGE TO
MUCH ABOVE AVERAGE CONDITIONS, PREVIOUS DRY CONDITIONS ARE LIKELY TO
IMPACT RUNOFF EFFICIENCY. JANUARY WATER SUPPLY FORECASTS HAVE A
HIGHER DEGREE OF UNCERTAINTY THAN FORECASTS LATER IN THE SEASON.
THESE EARLY SEASON FORECASTS CAN NOT ACCOUNT FOR SIGNIFICANT
VARIATIONS IN FUTURE WINTER AND SPRING WEATHER CONDITIONS.

JANUARY 1ST STREAMFLOW FORECASTS FROM THE NRCS WERE HIGHEST ON THE
OWYHEE RIVER BELOW WILDHORSE RESERVOIR AT 182 PERCENT OF AVERAGE,
AND LOWEST ON LAKE TAHOE INFLOW AT 84% OF AVERAGE. THE NWS FORECASTS
INDICATE BELOW AVERAGE STREAMFLOW EXPECTED ON THE MIDDLE FORK OF THE
FEATHER AND THE SUSAN RIVER.

BELOW ARE FORECASTS FOR SELECTED RIVER POINTS ACROSS NEVADA AND
EASTERN CALIFORNIA. SOME CONTAIN BOTH THE NRCS STATISTICAL FORECAST
AND NWS FORECAST PROVIDED BY THE ENSEMBLE STREAMFLOW PREDICTION
SYSTEM AT THE CALIFORNIA-NEVADA RIVER FORECAST CENTER. THE FORECASTS
DIFFER BASED ON FORECAST METHODOLOGY.

                      PERCENT OF AVERAGE APRIL TO JULY STREAMFLOW
                        MOST PROBABLE FORECAST AS OF JANUARY 1 2016
                          (50 PERCENT CHANCE OF EXCEEDANCE)
BASIN                                 NRCS    NWS
LAKE TAHOE INFLOW .................... 84 ... 69
TRUCKEE RIVER ........................ 98 ... 94  .. FARAD
CARSON RIVER ......................... 98 ... 84  .. CARSON CITY
WEST WALKER RIVER .................... 105... 93
EAST WALKER RIVER .................... 106... 77
NORTHERN GREAT ....................... 94 ... NA  .. 4 SITE AVERAGE
UPPER HUMBOLDT RIVER ................. 111... 124 .. PALISADE
LOWER HUMBOLDT RIVER ................. 98 ... 105 .. IMLAY
CLOVER VALLEY AND FRANKLIN RIVER ..... 101... NA
SNAKE RIVER..........................  159 ...82@ .. SALMON FALLS CK
OWYHEE RIVER ......................... 182... 93@
EASTERN NEVADA.......................  122... NA  .. 4 SITE AVERAGE
LAKE POWELL INFLOW   ................. 95 ... 89*
SUSAN RIVER........................... NA ... 72  .. SUSANVILLE (WATER YEAR)
MIDDLE FORK FEATHER RIVER............. NA ... 63  .. PORTOLA (WATER YEAR)

NA - FORECAST EITHER NOT AVAILABLE OR NOT PRODUCED FOR THIS LOCATION
     AT THE TIME OF THE REPORT
*  - LAKE POWELL INFLOW NWS FORECAST PROVIDED BY CBRFC IN SALT LAKE CITY
@  - SNAKE AND OWYHEE RIVER NWS FORECASTS PRODUCED BY NWRFC IN
     PORTLAND

6/ DROUGHT STATUS...

AS OF JANUARY 5, 2016 THE UNITED STATES DROUGHT MONITOR CLASSIFIED
91% OF NEVADA, ONLY EXCLUDING THE NORTHEASTERN PORTION OF ELKO
COUNTY, IN MODERATE DROUGHT OR WORSE.  THIS IS AN IMPROVEMENT FROM
97% A YEAR AGO.  EXTREME TO EXCEPTIONAL DROUGHT IS CLASSIFIED FOR
31% OF THE STATE INCLUDING ALL OF STOREY, CARSON CITY, DOUGLAS,
LYON, MINERAL, CHURCHILL, PERSHING, AND PORTIONS OF WASHOE,
HUMBOLDT, LANDER, NYE AND ESMERALDA COUNTIES.  THIS IS A DECREASE OF
17% FROM LAST YEAR.  IN CALIFORNIA 97% OF THE STATE IS CLASSIFIED IN
MODERATE DROUGHT OR WORSE ONLY EXCLUDING EASTERN PORTIONS OF SAN
BERNARDINO, RIVERSIDE, AND IMPERIAL COUNTIES, A DECREASE OF 1% FROM
LAST  YEAR.  EXTREME TO EXCEPTIONAL DROUGHT IS INDICATED IN 69% OF
THE STATE INCLUDING, BUT NOT LIMITED TO ALL OF MODOC, LASSEN,
PLUMAS, SIERRA, NEVADA, PLACER, EL DORADO, ALPINE, AND MONO
COUNTIES.

IF FAVORABLE SNOWPACK AND RUNOFF CONDITIONS PERSIST INTO LATE WINTER
AND SPRING, DROUGHT CLASSIFICATIONS WILL LIKELY BE SLOWLY REDUCED,
HOWEVER WATER SUPPLY DEFICITS ARE LIKELY TO CONTINUE DUE TO
EXTREMELY LOW RESERVOIR STORAGE AND DIMINISHED GROUND WATER LEVELS.

7/ LONG RANGE WEATHER OUTLOOK FOR NEVADA AND EASTERN CALIFORNIA.

THE OUTLOOK FOR THE REMAINDER OF JANUARY IS FOR INCREASED CHANCES OF
ABOVE NORMAL PRECIPITATION IN MOST OF CALIFORNIA, AND WEST CENTRAL
AND SOUTHERN NEVADA.  EQUAL CHANCES OF ABOVE, BELOW, OR NORMAL
PRECIPITATION ARE PROJECTED FOR NORTHERN CALIFORNIA AND NORTHERN
NEVADA.

THE OUTLOOK FOR THE MONTHS OF FEBRUARY THROUGH APRIL IS FOR
INCREASED CHANCES OF ABOVE NORMAL TEMPERATURE THROUGH MOST OF THE
REGION EXCLUDING ONLY SOUTHERN PORTIONS CALIFORNIA AND NEVADA AS
WELL AS EASTERN NEVADA, WHICH HAVE EQUAL CHANCES. HIGHER PROBABILITY
OF WARMER TEMPERATURES ARE PROJECTED FOR NORTHERN CALIFORNIA AND
NORTHWESTERN NEVADA.  INCREASED CHANCES OF ABOVE NORMAL
PRECIPITATION ARE PROJECTED FOR ALL OF THE REGION WITH THE EXCEPTION
OF FAR NORTHERN NEVADA. THE HIGHEST PROBABILITIES ARE PROJECTED FOR
SOUTHERN CALIFORNIA.


8/ FOR MORE DETAILED WATER SUPPLY AND STREAMFLOW FORECAST
INFORMATION FOR NEVADA AND EASTERN CALIFORNIA...PLEASE REFER TO THE
FOLLOWING WEB SITES /NOTE...ALL LETTERS IN WEB SITE ADDRESSES ARE
LOWER CASE/...

NWS CALIFORNIA NEVADA RIVER FORECAST CENTER...
HTTP://WWW.CNRFC.NOAA.GOV/WATER_SUPPLY.PHP

NEVADA NATURAL RESOURCES CONSERVATION SERVICE...
HTTP://WWW.NV.NRCS.USDA.GOV/SNOW/

CALIFORNIA DEPT. OF WATER RESOURCES...
HTTP://CDEC.WATER.CA.GOV/

NWS CLIMATE PREDICTION CENTER LONG RANGE OUTLOOK MAPS...
HTTP://WWW.CPC.NCEP.NOAA.GOV/PRODUCTS/FORECASTS/

U.S. DROUGHT PORTAL...INCLUDING U.S. DROUGHT MONITOR...
HTTP://DROUGHT.GOV/

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