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NVZ001>041-CAZ070>073-CAZ519>527-160000-

WATER SUPPLY OUTLOOK
NATIONAL WEATHER SERVICE RENO NV
400 AM PST SAT JAN 10 2015

...WATER SUPPLY OUTLOOK FOR NEVADA AND EASTERN CALIFORNIA AS OF
JANUARY 10 2015...

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

1/SUMMARY...WATER SUPPLY OUTLOOK...
BY EARLY JANUARY NORTHERN NEVADA HAD REAPED THE BENEFITS OF NEAR TO
SLIGHTLY ABOVE AVERAGE PRECIPITATION SINCE THE START OF OCTOBER.
HOWEVER...MUCH OF THE SIERRA NEVADA...FAR WESTERN NEVADA AND THE
LOWER ELEVATIONS OF EASTERN NEVADA WERE MISSED BY THE PRECIPITATION
THAT BOOSTED THE NORTHERN PART OF THE STATE.  EVEN WITH INCREASED
PRECIPITATION IN SOME PARTS OF THE REGION...THE PRECEDING THREE
YEARS HAVE LEFT RAINFALL DEFICITS OVER MUCH OF THE AREA.  IN SOME
PARTS OF WESTERN NEVADA AND THE SIERRA NEVADA MOUNTAINS UP TO 1 FULL
YEAR OF PRECIPITATION HAS BEEN MISSED IN THE LAST THREE YEARS. A
STORM IN MID DECEMBER DID BRING AN INCREASE IN SOIL MOISTURE FOR
PARTS OF THE AREA...BUT HIGH SNOW LEVELS DID LITTLE TO BOOST THE
MIDDLE AND LOW ELEVATION SNOW PACK.

THE REDUCED SNOWPACK AND RELATIVELY DRY SOILS IN THE SIERRA NEVADA
MOUNTAINS AND FAR WESTERN NEVADA ARE LIKELY TO RESULT IN REDUCED
RUNOFF LATER THIS SEASON AS THE SOILS WILL NEED TO BE SATURATED
BEFORE SIGNIFICANT RUNOFF OCCURS. AGRICULTURAL INTERESTS THAT DEPEND
ON WATER FROM WINTER SNOWS AND SPRING RUNOFF WILL NEED TO BE
PROACTIVE IN MANAGING WATER RESOURCES THIS YEAR. ACROSS FAR NORTHERN
NEVADA THE INCREASED SOIL MOISTURE MAY PROMOTE MORE RUNOFF.

RESERVOIR STORAGE REMAINS VERY LOW AS WELL...SO THERE IS LESS WATER
TO DRAW ON FROM PREVIOUS YEARS. WATER USERS THAT DEPEND ON THIS
STORAGE WILL ALSO NEED TO PREPARE FOR POTENTIALLY EXCEPTIONALLY DRY
CONDITIONS.

SMALL SNOWPACKS TEND TO RESULT IN AN EARLIER MELT AND GENERATE LESS
STREAMFLOW AND LOWER PEAK FLOWS THAN NORMAL OR ABOVE NORMAL SNOW
PACKS.

AS OF EARLY JANUARY...STREAMFLOW FORECASTS ARE EXPECTED TO BE WELL
BELOW TO MUCH BELOW AVERAGE FOR EASTERN NEVADA...WESTERN NEVADA AND
EASTERN CALIFORNIA THIS SPRING AND SUMMER UNLESS SNOWPACK CONDITIONS
IMPROVE. IN NORTHERN AND NORTH CENTRAL NEVADA STREAMFLOW FORECASTS
ARE EXPECTED TO BE SLIGHTLY AVERAGE TO NEAR AVERAGE.

THE NEXT SIX TO EIGHT WEEKS WILL TELL THE FINAL STORY OF SNOWPACK
THIS WINTER...AND WHAT THE SPRING AND SUMMER STREAMFLOW WILL BE.
JUST A FEW WET STORMS WOULD RESULT IN IMPROVED CONDITIONS...BUT
CURRENT LONG RANGE FORECASTS PROVIDE LOW CONFIDENCE IN A SHIFT TO A
WETTER PATTERN. THE OUTLOOK FOR FEBRUARY THROUGH APRIL CALLS FOR
ABOVE NORMAL PRECIPITATION FOR THE ENTIRE REGION.

2/SNOWPACK...
SNOWPACK AS OF JANUARY 1ST IN THE SIERRA NEVADA IS BELOW AVERAGE...
BUT IS HIGHER THAN AT THIS TIME LAST YEAR. SNOWPACK IN EASTERN
NEVADA IS ON PAR WITH WESTERN NEVADA.  THE SNOWPACK ACROSS NORTHERN
NEVADA IS HIGHER THAN THE WESTERN AND FAR EASTERN PARTS OF THE
STATE. MOST NORTHERN NEVADA BASINS ARE NEAR TO ABOVE AVERAGE. THE
HIGHEST SNOWPACK AS OF JANUARY 1 WAS IN THE CLOVER VALLEY
BASIN...THE OWYHEE BASIN AND THE SNAKE RIVER BASIN...ALL AT BETTER
THAN 120 PERCENT OF AVERAGE. THE LOWEST FOR AREAS THAT REPORTED WAS
THE LAKE TAHOE BASIN AT 43 PERCENT OF AVERAGE.

                                  JAN 1 2015
BASIN                PERCENT OF MEDIAN
LAKE TAHOE ........................  43
TRUCKEE RIVER .....................  65
CARSON RIVER ......................  63
WALKER RIVER ......................  68
NORTHERN GREAT .................... 102
UPPER HUMBOLDT RIVER .............. 124
LOWER HUMBOLDT RIVER ..............  71
CLOVER VALLEY & FRANKLIN RIVER .... 146
SNAKE RIVER ....................... 121
OWYHEE RIVER ...................... 122
EASTERN NEVADA ....................  80
LOWER COLORADO RIVER ..............  NA

3/PRECIPITATION...
THE FIRST THREE MONTHS OF THE WATER YEAR RESULTED IN BELOW AVERAGE
PRECIPITATION FOR FAR WESTERN NEVADA AND EASTERN CALIFORNIA.
PRECIPITATION IN THE SIERRA NEVADA MOUNTAINS AND WESTERN NEVADA
RANGED FROM AROUND 55 TO 75 PERCENT OF AVERAGE. PRECIPITATION IN
EASTERN NEVADA AVERAGED AROUND 70 PERCENT OF AVERAGE.

THE NORTHERN PORTION OF NEVADA FARED MUCH BETTER WITH MANY BASINS
RECEIVING ABOVE AVERAGE PRECIPITATION FROM OCTOBER THROUGH DECEMBER.
THESE BASINS AVERAGED FROM AROUND 98 PERCENT TO NEAR 120 PERCENT OF
AVERAGE.

DECEMBER WAS BELOW AVERAGE IN THE SIERRA AND FAR WESTERN
NEVADA...BUT WAS ABOVE NORMAL FOR NORTHWEST NEVADA AND THE FAR
NORTHERN PART OF THE STATE. A STORM IN MID DECEMBER BROUGHT THESE
AREAS TO WELL ABOVE NORMAL FOR THE MONTH. UNFORTUNATELY...SNOW
LEVELS REMAINED FAIRLY HIGH THROUGH MUCH OF THIS STORM. ALTHOUGH
PRECIPITATION AVERAGES INCREASED...MUCH OF THE LOWER ELEVATIONS
DID NOT SEE A CORRESPONDING INCREASE IN SNOWPACK. HIGH ELEVATIONS
DID PICK UP SUBSTANTIAL SNOW DURING THIS TIME.

                                WATER YEAR 2015
                              /THROUGH 1/8/2015/
BASIN                         PERCENT OF AVERAGE
LAKE TAHOE .........................  65
TRUCKEE RIVER ......................  74
CARSON RIVER .......................  59
WALKER RIVER .......................  57
NORTHERN GREAT ..................... 117
UPPER HUMBOLDT RIVER ...............  98
LOWER HUMBOLDT RIVER ............... 104
CLOVER VALLEY AND FRANKLIN RIVER ... 118
SNAKE RIVER ........................ 106
OWYHEE RIVER ....................... 113
EASTERN NEVADA .....................  71
LOWER COLORADO RIVER ...............  NA

4/RESERVOIRS...
STORAGE IN MOST RESERVOIRS IN NEVADA AND EASTERN CALIFORNIA WERE
WELL BELOW AVERAGE TO START THE YEAR. IN EARLY JANUARY RESERVOIR
STORAGE IN NORTHERN NEVADA AND EASTERN CALIFORNIA VARIED FROM A HIGH
OF 48 PERCENT OF AVERAGE ON THE TRUCKEE RIVER BASIN TO A LOW OF 0
PERCENT OF AVERAGE IN THE LAKE TAHOE BASIN. THIS 0 PERCENT AT LAKE
TAHOE IS DUE TO THE LAKE`S FALLING BELOW ITS NATURAL RIM IN LATE
FALL. IN SOUTHERN NEVADA THE LOWER COLORADO BASIN HAD A STORAGE OF
56 PERCENT OF AVERAGE.

BASIN                        PERCENT OF CAPACITY   PERCENT OF AVERAGE
LAKE TAHOE ........................   0 ................   0
TRUCKEE RIVER .....................  28 ................  48
CARSON RIVER ......................   5 ................  12
WALKER RIVER ......................  10 ................  29
LOWER HUMBOLDT RIVER ..............   5 ................  14
OWYHEE RIVER ......................  16 ................  35
LOWER COLORADO RIVER ..............  44 ................  56

5/STREAMFLOW...
APRIL THROUGH JULY STREAMFLOW FORECASTS FOR MUCH OF NEVADA AND
EASTERN CALIFORNIA AS OF JANUARY 1ST ARE FORECAST TO BE BELOW TO
WELL BELOW AVERAGE.  FOR PARTS OF NORTHERN NEVADA STREAMFLOW
FORECASTS ARE EXPECTED TO BE FROM NEAR AVERAGE TO SLIGHTLY BELOW
AVERAGE IF A TYPICAL PRECIPITATION PATTERN IS EXPERIENCED THROUGH
THE REMAINDER OF THE WINTER AND EARLY SPRING. FOR SOUTHERN NEVADA
STREAMFLOWS ON THE VIRGIN RIVER ARE EXPECTED TO BE WELL BELOW
AVERAGE.

JANUARY 1ST STREAMFLOW FORECASTS WERE HIGHEST ON THE SNAKE RIVER AT
106 PERCENT OF AVERAGE AND LOWEST ON THE VIRGIN RIVER IN THE LOWER
COLORADO BASIN AT 35 PERCENT OF AVERAGE. THE CARSON RIVER AT CARSON
CITY IS ALSO FORECAST TO BE QUITE LOW AT 39 PERCENT OF AVERAGE.

                    PERCENT OF AVERAGE APRIL TO JULY STREAMFLOW
                 MOST PROBABLE FORECAST FROM NRCS AS OF JAN 1 2015
BASIN                    (50 PERCENT CHANCE OF EXCEEDANCE)
LAKE TAHOE RISE ...................... 53
TRUCKEE RIVER ........................ 61 .. FARAD
CARSON RIVER ......................... 39 .. CARSON CITY
WEST WALKER RIVER .................... 64
EAST WALKER RIVER .................... 60
NORTHERN GREAT ....................... 42 .. MCDERMITT
UPPER HUMBOLDT RIVER ................. 84 .. PALISADE
LOWER HUMBOLDT RIVER ................. 59 .. IMLAY
CLOVER VALLEY AND FRANKLIN RIVER ..... 72
SNAKE RIVER ..........................106
OWYHEE RIVER ......................... 84
EASTERN NEVADA ....................... 63 .. ELY
LOWER COLORADO RIVER ................. 35 .. LITTLEFIELD

6/ DROUGHT STATUS...
AS OF JANUARY 6 2015...THE UNITED STATES DROUGHT MONITOR CLASSIFIED
PORTIONS OF WEST CENTRAL NEVADA...INCLUDING CHURCHILL...PERSHING...
STOREY...CARSON CITY...WESTERN LANDER...SOUTHERN WASHOE AND WESTERN
DOUGLAS COUNTIES IN NEVADA AS IN EXCEPTIONAL DROUGHT /LEVEL 4 OF 4
LEVELS OF DROUGHT/. IN CALIFORNIA...PARTS OF LASSEN...PLUMAS...
SIERRA...NEVADA...PLACER...EL DORADO AND ALPINE COUNTIES WERE
CLASSIFIED IN EXCEPTIONAL DROUGHT. THE REMAINDER OF EASTERN
CALIFORNIA AND WESTERN NEVADA WAS CLASSIFIED AS IN EXTREME DROUGHT
/LEVEL 3 OF 4 LEVELS OF DROUGHT/. IN EASTERN AND SOUTHERN NEVADA...
PARTS OF ELKO...EUREKA...NYE...LINCOLN AND CLARK COUNTIES WERE
CLASSIFIED AS HAVING EXTREME DROUGHT WHILE THE BULK OF EASTERN AND
SOUTHERN NEVADA WAS CLASSIFIED AS BEING EITHER ABNORMALLY DRY OR
HAVING MODERATE TO SEVERE DROUGHT. PARTS OF SOUTH INYO COUNTY AND
MUCH OF SAN BERNARDINO COUNTY WERE ALSO NOTED AS BEING ABNORMALLY
DRY OR HAVING MODERATE TO SEVERE DROUGHT.

POSSIBLE IMPACTS FROM DROUGHT IN NEVADA AND EASTERN CALIFORNIA
INCLUDE...

HIGH FIRE DANGER THIS COMING SUMMER...AS TEMPERATURES WARM AND FUELS
DRY.

POSSIBLE WATER SUPPLY DEFICITS...RESERVOIR STORAGE REMAINS LOW AND
WATER SUPPLY COULD BECOME AN ISSUE THROUGHOUT THE REGION THIS SPRING
AND SUMMER IF SIGNIFICANT PRECIPITATION DOES NOT OCCUR OVER THE NEXT
FEW WEEKS. WATER SUPPLY CONCERNS WOULD BE HIGHEST ON BASINS WITHOUT
RESERVOIR STORAGE.

7/ LONG RANGE WEATHER OUTLOOK FOR NEVADA AND EASTERN CALIFORNIA...
THE OUTLOOK FOR LATE JANUARY...IS FOR BELOW NORMAL PRECIPITATION FOR
FAR NORTHERN NEVADA AND FAR NORTHEAST CALIFORNIA WITH ABOVE NORMAL
PRECIPITATION FOR FAR SOUTHERN NEVADA AND SOUTHEAST CALIFORNIA. THE
REST OF THE REGION HAS EQUAL CHANCES OF ABOVE...NEAR AND BELOW
NORMAL PRECIPITATION. TEMPERATURES ARE EXPECTED TO BE ABOVE NORMAL
FOR ALL OF NEVADA AND EASTERN CALIFORNIA.

THE LONG RANGE OUTLOOK FOR THE MONTHS OF FEBRUARY THROUGH APRIL IS
FOR ABOVE NORMAL PRECIPITATION ACROSS ALL OF NEVADA AND EASTERN
CALIFORNIA. TEMPERATURES DURING THIS PERIOD ARE EXPECTED TO BE ABOVE
NORMAL FOR THE ENTIRE REGION.

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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