Flood Potential Outlook
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WATER SUPPLY OUTLOOK
NATIONAL WEATHER SERVICE RENO NV
1330 PM PST MON FEB 08 2016

...WATER SUPPLY OUTLOOK FOR NEVADA AND EASTERN CALIFORNIA AS OF
FEB 08 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 MOST 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. JANUARY FINISHED
STRONG WITH TWO STORMS IN THE LAST THREE DAYS BUILDING THE REGION`S
SNOWPACK AND TEMPORALLY RAISING MANY RIVERS.

JANUARY IS A CRITICAL MONTH OF SNOW ACCUMULATION IN THE AREA, AND
THIS JANUARY DELIVERED CONSISTENTLY ABOVE AVERAGE ACCUMULATION
THROUGHOUT THE MOUNTAINS OF THE REGION.  IN FACT, IT WAS THE FIRST
JANUARY CONSISTENTLY ABOVE AVERAGE FOR PRECIPITATION AND SNOW
ACCUMULATION FOR THE ENTIRE REGION SINCE 2008.

THE MOUNTAIN SNOWPACK GOT OFF TO AN EARLY START AND NEAR NORMAL
TEMPERATURES COMBINED WITH FREQUENT MODERATE STORMS HAVE CONTINUED
TO BUILD AN EXCELLENT MID-WINTER SNOWPACK.  THIS IS ENCOURAGING
AFTER FOUR DRY WINTERS, BUT WITH TWO MORE MONTHS OF THE SNOW
ACCUMULATION SEASON REMAINING, A WIDE VARIETY OF OUTCOMES ARE STILL
POSSIBLE.  WHILE THE CURRENT SNOWPACK ALREADY EXCEEDS THE LAST THREE
YEARS` PEAKS IN MOST BASINS, THE RUNOFF EFFICIENCY AND TOTAL RUNOFF
PRODUCED WILL BE VERY DEPENDENT ON THE WEATHER OVER THE NEXT THREE
MONTHS.

JANUARY ENDED WITH A MODERATELY STRONG ATMOSPHERIC RIVER EVENT,
BENEFITING SNOWPACK CONDITIONS AND TEMPORARILY RAISING MANY RIVERS.
THESE FLOWS HELPED IMPROVE RESERVOIR STORAGE SOMEWHAT IN THE EASTERN
SIERRA, BUT THERE IS STILL A LONG WAY TO GO TO FILL RESERVOIRS AFTER
FOUR YEARS OF BELOW AVERAGE SNOWPACKS AND LOW STREAMFLOWS. RESERVOIR
STORAGE AND GENERAL WATER SUPPLY CONDITIONS REMAIN POOR. THE
ANTICIPATED 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 FEBRUARY 1ST, RANGES FROM ABOVE AVERAGE AT 114% ON
THE TRUCKEE BASIN TO A HIGH OF 158% FOR THE NORTHERN GREAT BASIN.
ALL BASINS IN NORTHERN AND EASTERN NEVADA ARE MUCH ABOVE AVERAGE.

AS OF FEBRUARY 2ND ONE SNOTEL SITE, CEDAR PASS IN NORTHEASTERN
CALIFORNIA HAD THEIR SECOND HIGHEST SNOW WATER EQUIVALENT (SWE) TO
DATE FOR THE 38 YEAR PERIOD OF RECORD.

ON AVERAGE PEAK BASIN SNOWPACK OCCURS BETWEEN MID-MARCH AND EARLY
APRIL.  CURRENTLY THE TAHOE, TRUCKEE, CARSON AND WALKER BASINS HAVE
NEAR 80% OF THEIR AVERAGE PEAK SNOWPACK WHILE BASINS TO THE NORTH
AND EAST HAVE NEAR 100% OF AVERAGE BASIN PEAK CONDITIONS.  EVEN
CONSIDERING THESE HIGH SNOWPACK NUMBERS, A CONTINUATION OF COOL
TEMPERATURES AND FREQUENT STORMS WILL BE NEEDED TO PRODUCE AVERAGE
OR ABOVE AVERAGE RUNOFF CONDITIONS.  EARLY SNOWMELT RUNOFF TENDS TO
BE INEFFICIENT AND ABOVE AVERAGE LATE SPRING SNOW CONDITIONS WILL
LIKELY BE NECESSARY TO PRODUCE NEAR AVERAGE RUNOFF AFTER FOUR YEARS
OF DROUGHT.

                                 FEB 1 2016
BASIN                    PERCENT OF MEDIAN
LAKE TAHOE ........................   130
TRUCKEE RIVER .....................   114
CARSON RIVER ......................   127
WALKER RIVER ......................   117
NORTHERN GREAT ....................   158
UPPER HUMBOLDT RIVER ..............   135
LOWER HUMBOLDT RIVER ..............   157
CLOVER VALLEY & FRANKLIN RIVER ....   134
SNAKE RIVER .......................   152
OWYHEE RIVER ......................   151
EASTERN NEVADA ....................   152
LOWER COLORADO RIVER ..............   NA


3/PRECIPITATION...

CURRENT WATER YEAR-TO-DATE PRECIPITATION AS OF FEBRUARY 1ST IS ABOVE
TO MUCH ABOVE NORMAL THROUGHOUT NEVADA. BASINS DRAINING TO THE EAST
SLOPE OF THE SIERRA ARE ABOVE AVERAGE AND CONDITIONS GET
PROGRESSIVELY WETTER TO THE EAST WITH THE FAR EASTERN NEVADA AREA AT
172%. UNLIKE MOST RECENT JANUARYS WHICH WERE DOMINATED BY HIGH
PRESSURE, EACH BASIN REPORTED ABOVE AVERAGE MOUNTAIN PRECIPITATION
THIS JANUARY. LAKE TAHOE AND EASTERN NEVADA REPORTED 155% AND 154%
OF AVERAGE RESPECTIVELY, WHILE THE SNAKE RIVER BASIN IN NORTHEASTERN
NEVADA HAD THE DRIEST JANUARY AT 113% OF AVERAGE.

AS OF FEBRUARY 2ND, DIAMOND PEAK AND CORAL CANYON SNOTELS HAVE
RECORD HIGH WATER YEAR-TO-DATE PRECIPITATION WHILE GREEN MOUNTAIN
AND POLE CREEK SNOTELS HAVE THE SECOND HIGHEST WATER YEAR-TO-DATE
PRECIPITATION FOR THE PERIOD OF RECORD. ALL OF THESE SITES ARE IN
EASTERN AND NORTHEASTERN NEVADA.


                                                  WATER YEAR 2016
                                    JAN 2015    /THROUGH 01/31/2016/
BASIN                              PCT OF AVE        PCT OF AVE
LAKE TAHOE .........................   155 ...........   132
TRUCKEE RIVER ......................   147 ...........   119
CARSON RIVER .......................   126 ...........   120
WALKER RIVER .......................   124 ...........   122
NORTHERN GREAT .....................   139 ...........   136
UPPER HUMBOLDT RIVER ...............   118 ...........   145
LOWER HUMBOLDT RIVER ...............   144 ...........   145
CLOVER VALLEY AND FRANKLIN RIVER ...   128 ...........   149
SNAKE RIVER ........................   113 ...........   145
OWYHEE RIVER .......................   116 ...........   136
EASTERN NEVADA .....................   154 ...........   172
LOWER COLORADO RIVER ...............   NA  ...........   NA


4/RESERVOIRS...

MOST RESERVOIRS IN THE AREA DID MAKE SMALL GAINS IN STORAGE SINCE
LAST MONTH INCLUDING 63,000 ACRE-FEET IN LAKE TAHOE AND OTHER
TRUCKEE SYSTEM RESERVOIRS, 12,000 ACRE-FEET IN LAHONTAN, AND 7,000
ACRE-FEET ON IN UPPER WALKER RESERVOIRS. DESPITE THESE GAINS,
RESERVOIRS IN THE AREA ARE STILL WELL BELOW AVERAGE WITH LOTS OF
ROOM TO FILL. FOR EXAMPLE, LAKE TAHOE MEASURED 0.95 FEET OR 115,000
ACRE-FEET BELOW THE NATURAL RIM WITH ANOTHER 7 VERTICAL FEET NEEDED
TO REACH CAPACITY. RYE PATCH RESERVOIR ON THE LOWER HUMBOLDT GAINED
ONLY 200 ACRE-FEET IN JANUARY AND REMAINS AT 5% OF CAPACITY.
STREAMFLOW FORECASTS ARE ENCOURAGING, INDICATING THAT THIS YEAR WILL
LIKELY PROVIDE SIGNIFICANT FLOWS TO START REFILLING THE SYSTEM.

BASIN                      PERCENT OF CAPACITY   PERCENT OF AVERAGE
LAKE TAHOE ........................   0 ................   0
TRUCKEE RIVER .....................  22 ................  38
CARSON RIVER ......................   8 ................  17
WALKER RIVER  ...................... 23 ................  52
LOWER HUMBOLDT RIVER ..............   5 ................  13
OWYHEE RIVER ......................  16 ................  33
LOWER COLORADO RIVER ..............  43 ................  54


5/STREAMFLOW...

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

FEBRUARY 1ST STREAMFLOW FORECASTS FROM THE NRCS WERE HIGHEST ON THE
OWYHEE RIVER BELOW WILDHORSE RESERVOIR AT 191 PERCENT OF AVERAGE,
AND LOWEST ON THE LOWER HUMBOLDT AT 90% OF AVERAGE. THE NWS FORECASTS
INDICATE BELOW AVERAGE STREAMFLOW EXPECTED ON THE MIDDLE FORK OF THE
FEATHER.

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 FEBRUARY 1 2016
                     (50 PERCENT CHANCE OF EXCEEDANCE)

BASIN                                NRCS     NWS
LAKE TAHOE INFLOW..................... 99 ... 101
TRUCKEE RIVER.........................102 ... 102  .. FARAD
CARSON RIVER .........................103 ...  92  .. CARSON CITY
WEST WALKER RIVER ....................110 ...  98
EAST WALKER RIVER ....................110 ...  90
NORTHERN GREAT ....................... 95 ...  NA  .. 4 SITE AVERAGE
UPPER HUMBOLDT RIVER .................111 ... 141  .. PALISADE
LOWER HUMBOLDT RIVER ................. 90 ... 143  .. IMLAY
CLOVER VALLEY AND FRANKLIN RIVER .....103 ...  NA
SNAKE RIVER...........................153 ...  90@ .. SALMON FALLS CK
OWYHEE RIVER .........................191 ...  82@
EASTERN NEVADA....................... 122 ...  NA  .. 4 SITE AVERAGE
LAKE POWELL INFLOW   ................. 98 ...  94*
SUSAN RIVER........................... NA ...  90  .. SUSANVILLE (WATER YEAR)
MIDDLE FORK FEATHER RIVER............. NA ...  71  .. 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 FEBRUARY 2, 2016, THE UNITED STATES DROUGHT MONITOR CLASSIFIED
72% OF NEVADA, ONLY EXCLUDING THE NORTHEASTERN PORTION OF ELKO
COUNTY, IN MODERATE DROUGHT OR WORSE. THIS IS AN IMPROVEMENT FROM
91% A MONTH AGO AND 100% A YEAR AGO. MOST OF THESE IMPROVEMENTS ARE
IN EASTERN NEVADA INCLUDING PORTIONS OF ELKO, WHITE PINE, LINCOLN,
AND CLARK COUNTY. EXTREME TO EXCEPTIONAL DROUGHT IS CLASSIFIED FOR
25% OF THE STATE INCLUDING ALL OF STOREY, CARSON CITY, DOUGLAS,
LYON, MINERAL, CHURCHILL, AND PORTIONS OF WASHOE, PERSHING,
HUMBOLDT, LANDER, NYE AND ESMERALDA COUNTIES. THIS IS A DECREASE OF
22% FROM LAST YEAR. IN CALIFORNIA 95% OF THE STATE IS CLASSIFIED IN
MODERATE DROUGHT OR WORSE ONLY EXCLUDING EASTERN PORTIONS OF SAN
BERNARDINO, RIVERSIDE, AND IMPERIAL COUNTIES, AND WESTERN PORTIONS
OF DEL NORTE AND HUMBOLDT COUNTIES A DECREASE OF 3% FROM LAST YEAR.
EXTREME TO EXCEPTIONAL DROUGHT IS INDICATED IN 64% 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 CONTINUE TO BE
SLOWLY REDUCED, HOWEVER WATER SUPPLY DEFICITS ARE LIKELY TO CONTINUE
DUE TO EXTREMELY LOW RESERVOIR STORAGE, DIMINISHED GROUND WATER
LEVELS, AND ASSOCIATED IMPACTS TO FORESTS AND OTHER NATURAL
RESOURCES.


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

FEBRUARY IS OFF TO A DRY START WITH THE STRONGEST HIGH PRESSURE
RIDGE OF THE WINTER EXPECTED TO KEEP THE AREA DRY AND WARM THROUGH
THE FIRST TWO WEEKS OF THE MONTH. THE OUTLOOK FOR THE REMAINDER OF
FEBRUARY IS FOR INCREASED CHANCES OF ABOVE NORMAL PRECIPITATION IN
MOST OF CALIFORNIA AND NEVADA, AND EQUAL CHANCES OF ABOVE, BELOW,
OR NORMAL PRECIPITATION FOR NORTHERN CALIFORNIA AND NORTHERN NEVADA.
FEBRUARY TEMPERATURES HAVE AN INCREASED CHANCE OF BEING ABOVE NORMAL
THROUGHOUT THE REGION.

THE OUTLOOK FOR THE MONTHS OF MARCH THROUGH MAY IS FOR
INCREASED CHANCES OF ABOVE NORMAL TEMPERATURE THROUGHOUT THE REGION,
EXCLUDING ONLY EXTREME SOUTHERN CALIFORNIA AND SOUTHEASTERN 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 THE SOUTHERN HALF OF
CALIFORNIA AND NEVADA.


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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