Flood Potential Outlook
Issued by NWS Reno, NV

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NVZ001>041-CAZ070>073-CAZ519>527-130000-

WATER SUPPLY OUTLOOK
NATIONAL WEATHER SERVICE RENO NV
230 AM PST TUE APR 8 2014

...WATER SUPPLY AND SPRING FLOOD POTENTIAL OUTLOOK FOR NEVADA AND
EASTERN CALIFORNIA AS OF APRIL 8 2014...

...FLOOD POTENTIAL IN NEVADA AND EASTERN CALIFORNIA IS BELOW AVERAGE
THIS SPRING...

...WELL BELOW AVERAGE STREAMFLOW IS EXPECTED THIS SPRING AND SUMMER
REGION WIDE...

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

1/SUMMARY...SPRING FLOOD POTENTIAL OUTLOOK...
THE SPRING FLOOD POTENTIAL IN ALL BASINS IN NEVADA AND THE
WATERSHEDS EAST OF SIERRA CREST IN EASTERN CALIFORNIA IS BELOW
AVERAGE THIS SPRING.

SPRING FLOOD POTENTIAL DEPENDS ON SEVERAL FACTORS. THESE INCLUDE
SNOWPACK...SOIL MOISTURE AND RESERVOIR STORAGE ALONG WITH AIR
TEMPERATURE AND RAINFALL DURING THE SNOWMELT PERIOD.

PRECIPITATION HAS BEEN BELOW AVERAGE IN MOST OF THE REGION SINCE THE
START OF THE WATER YEAR IN OCTOBER 2013. PRECIPITATION IN FEBRUARY
HELPED BOOST THE SNOWPACK AND SOIL MOISTURE...BUT PRECIPITATION WAS
ONCE AGAIN BELOW AVERAGE IN MARCH. DUE TO PROLONGED DROUGHT THE SOIL
MOISTURE REMAINS BELOW WHAT WOULD BE CONSIDERED NORMAL FOR EARLY
APRIL AND SNOWPACK REMAINS BELOW NORMAL.

RESERVOIR STORAGE HAS INCREASED IN THE LAST TWO MONTHS DUE TO STORM
SYSTEMS IN FEBRUARY AND MARCH...BUT REMAINS BELOW AVERAGE...AND WELL
BELOW AVERAGE FOR THE EASTERN SIERRA AND WESTERN NEVADA.

THE BEST SNOWPACK CONDITIONS ARE IN THE UPPER HUMBOLDT RIVER AND
EASTERN NEVADA WATERSHEDS.

2/SUMMARY...WATER SUPPLY OUTLOOK...STORMS IN EARLY FEBRUARY AND LATE
MARCH BROUGHT MARGINALLY IMPROVED SNOWPACK CONDITIONS IN NEVADA AND
THE EASTERN SIERRA. THESE STORMS PUSHED THE SNOWPACK ABOVE THE NEAR
HISTORICAL LOWS THAT HAD BEEN SEEN THROUGH LATE JANUARY. BUT EVEN
WITH THESE STORMS THE SNOWPACK REMAINS WELL BELOW AVERAGE OVER ALL
OF THE EASTERN SIERRA AND WESTERN NEVADA FOR EARLY APRIL. SOIL
MOISTURE ALSO IMPROVED THROUGH THE PAST TWO MONTHS AS EARLY SNOW
MELT BEGINS TO SATURATE SOILS. STILL...MOST BASINS REMAIN AT OR
SLIGHTLY BELOW AVERAGE CONDITIONS...WITH THE WALKER AND EASTERN
NEVADA BASINS SHOWING WELL BELOW AVERAGE CONDITIONS.

THE WELL BELOW AVERAGE SNOWPACK AND BELOW AVERAGE SOIL MOISTURE MEAN
ANY RUNOFF LATER THIS SEASON WILL BE REDUCED AS THE SOILS WILL NEED
TO BE FURTHER 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.

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

SMALL SNOWPACKS TEND TO RESULT IN AN EARLIER MELT AND GENERATE LESS
STREAMFLOW...LOWER PEAK FLOWS...MORE INFILTRATION LOSS AND A LONGER
IRRIGATION SEASON THAN SEEN WITH A NORMAL OR ABOVE NORMAL SNOWPACK.

AS OF EARLY APRIL...STREAMFLOW FORECASTS ARE EXPECTED TO BE BELOW TO
MUCH BELOW AVERAGE THIS SPRING AND SUMMER UNLESS SIGNIFICANT
SNOWPACK CONDITIONS IMPROVE.

3/SNOWPACK...
SNOWPACK IN THE EASTERN SIERRA AND WESTERN NEVADA IMPROVED
MARGINALLY OVER THE LAST MONTH BUT REMAINS QUITE LOW AS OF EARLY
APRIL RANGING FROM 35 TO 63 PERCENT. EASTERN NEVADA AND THE UPPER
HUMBOLDT BASIN ALSO IMPROVED REACHING FROM 72 TO AS MUCH 113
PERCENT OF AVERAGE. THE NORTHERN GREAT BASIN IMPROVED THE
MOST...RISING FROM 7 PERCENT IN EARLY MARCH TO 59 PERCENT IN EARLY
APRIL AS MARCH STORMS WERE MORE GENEROUS TO NORTHWEST NEVADA THAN
ANY OTHER PART OF THE STATE.

                                  APR 3 2014
BASIN                PERCENT OF MEDIAN
LAKE TAHOE ........................  48
TRUCKEE RIVER .....................  35
CARSON RIVER ......................  63
WALKER RIVER ......................  48
NORTHERN GREAT ....................  59
UPPER HUMBOLDT RIVER .............. 103
LOWER HUMBOLDT RIVER ..............  62
CLOVER VALLEY & FRANKLIN RIVER .... 113
SNAKE RIVER .......................  74
OWYHEE RIVER ......................  74
EASTERN NEVADA ....................  72
LOWER COLORADO RIVER ..............  NA

4/PRECIPITATION...
PRECIPITATION OVER THE FIRST SIX MONTHS OF THE WATER YEAR REMAINS
WELL BELOW AVERAGE FOR MUCH OF NEVADA AND EASTERN CALIFORNIA. WATER
YEAR PRECIPITATION IN THE SIERRA AND WESTERN NEVADA RANGED FROM
AROUND 55 TO 66 PERCENT OF AVERAGE WHILE PRECIPITATION IN EASTERN
AND NORTHEAST NEVADA RANGED FROM 73 TO 91 PERCENT OF AVERAGE. THE
EXCEPTION WAS THE CLOVER VALLEY AND FRANKLIN RIVER BASIN WERE WATER
YEAR PRECIPITATION HAS CLIMBED TO JUST ABOVE AVERAGE.

MARCH PRECIPITATION WAS WELL BELOW AVERAGE FOR MUCH OF EASTERN...
SOUTHEAST...AND FAR WESTERN NEVADA AS WELL AS EASTERN SAN BERNARDINO
COUNTY AND SOUTHEAST INYO COUNTY IN EASTERN CALIFORNIA. MEANWHILE...
PRECIPITATION WAS ABOVE TO WELL ABOVE AVERAGE FOR NORTHEAST
CALIFORNIA...NORTHWEST AND NORTH CENTRAL NEVADA.

FOR CONSISTENCY PURPOSES MONTHLY AND WATER YEAR PRECIPITATION TOTALS
ARE BASED ON NRCS MEASUREMENTS.

                                WATER YEAR 2014
                              /THROUGH 4/5/2014/     MARCH 2014
BASIN                         PERCENT OF AVERAGE  PERCENT OF AVERAGE
LAKE TAHOE .........................  66                  76
TRUCKEE RIVER ......................  55                  74
CARSON RIVER .......................  60                  65
WALKER RIVER .......................  55                  64
NORTHERN GREAT .....................  62                 106
UPPER HUMBOLDT RIVER ...............  90                 106
LOWER HUMBOLDT RIVER ...............  81                 124
CLOVER VALLEY AND FRANKLIN RIVER ... 105                 143
SNAKE RIVER ........................  76                 116
OWYHEE RIVER .......................  80                 134
EASTERN NEVADA .....................  77                  44
LOWER COLORADO RIVER ...............  NA                  NA

5/RESERVOIRS...
EARLY APRIL RESERVOIR STORAGE IN NORTHERN NEVADA AND EASTERN
CALIFORNIA VARIED FROM A HIGH OF 67 PERCENT OF AVERAGE ON THE
TRUCKEE RIVER BASIN TO A LOW OF 9 PERCENT OF AVERAGE ON THE LOWER
HUMBOLDT RIVER BASIN. RESERVOIR STORAGE FOR MUCH OF THE AREA
REMAINED NEARLY STEADY THROUGH THE MONTH OF MARCH.

BASIN                        PERCENT OF CAPACITY   PERCENT OF AVERAGE
LAKE TAHOE ........................  20 ................  38
TRUCKEE RIVER .....................  42 ................  67
CARSON RIVER ......................  32 ................  48
WALKER RIVER ......................  18 ................  27
LOWER HUMBOLDT RIVER ..............   5 ................   9
OWYHEE RIVER ......................  22 ................  40
LOWER COLORADO RIVER ..............  48 ................  61

6/STREAMFLOW...
APRIL THROUGH JULY STREAMFLOW FORECASTS FOR NEVADA AND EASTERN
CALIFORNIA AS OF APRIL 1ST ARE FORECAST TO BE WELL BELOW AVERAGE FOR
WESTERN AND NORTHERN NEVADA AND THE EASTERN SIERRA...AND BELOW
AVERAGE FOR EASTERN NEVADA. FOR SOUTHERN NEVADA STREAMFLOWS ON THE
VIRGIN RIVER ARE EXPECTED TO BE WELL BELOW AVERAGE.

                        PERCENT OF AVERAGE APRIL TO JULY STREAMFLOW
                         MOST PROBABLE FORECAST AS OF APR 1 2014
                            (50 PERCENT CHANCE OF EXCEEDANCE)
BASIN                                     NRCS
LAKE TAHOE RISE .......................... 31
TRUCKEE RIVER .(FARAD).................... 37
CARSON RIVER ..(CARSON CITY).............. 25
WEST WALKER RIVER ........................ 36
EAST WALKER RIVER ..(BRIDGEPORT).......... 28 **
NORTHERN GREAT .....(MCDERMITT)........... 32
UPPER HUMBOLDT RIVER .(PALISADE).......... 47
LOWER HUMBOLDT RIVER .(IMLAY)............. 13
CLOVER VALLEY AND FRANKLIN RIVER ......... 58
SNAKE RIVER .............................. 46
OWYHEE RIVER ............................. 17
EASTERN NEVADA .......(AUSTIN)............ 61
LOWER COLORADO RIVER .(LITTLEFIELD)....... 15

** - APRIL TO AUGUST FORECAST

                                           APRIL-JULY 50%
                                        EXCEEDANCE FORECAST
                                               (KAF)
FORECAST POINT                                 NRCS
LAKE TAHOE RISE                             0.40 FEET ***
TRUCKEE RIVER AT FARAD                          95
WEST FORK CARSON RIVER AT WOODFORDS             21
EAST FORK CARSON RIVER AT GARDNERVILLE          60
CARSON RIVER AT CARSON CITY                     45
WEST WALKER RIVER BLO LTL WALKER                58
EAST WALKER NEAR BRIDGEPORT                     19 **
HUMBOLDT RIVER NEAR PALISADE                   105
HUMBOLDT RIVER NEAR IMLAY                       25

*** - LAKE TAHOE RISE GIVEN AS FEET WITH GATES CLOSED

7/ DROUGHT STATUS...
AS OF APRIL 3RD 2014...THE UNITED STATES DROUGHT MONITOR CLASSIFIED
PORTIONS OF WEST CENTRAL NEVADA...INCLUDING MUCH OF CHURCHILL AND
PERSHING COUNTIES ALONG WITH WESTERN LANDER COUNTY AS IN EXCEPTIONAL
DROUGHT /LEVEL 4 OF 4 LEVELS OF DROUGHT/. CARSON CITY ALONG WITH ALL
OF DOUGLAS...LYON...STOREY AND WASHOE COUNTIES...THE REMAINDER OF
CHURCHILL...LANDER AND PERSHING COUNTIES...AND PARTS OF ELKO...
EUREKA...HUMBOLDT AND MINERAL COUNTIES WERE CLASSIFIED AS IN EXTREME
DROUGHT /LEVEL 3 OF 4 LEVELS OF DROUGHT/.

IN EASTERN CALIFORNIA ALL AREAS WITH THE EXCEPTION OF EXTREME
SOUTHEAST MONO...EASTERN INYO AND ALL BUT FAR WESTERN SAN BERNARDINO
COUNTIES WERE CLASSIFIED IN EXTREME DROUGHT AS WELL.

THE REMAINDER OF NEVADA AND EASTERN CALIFORNIA WAS CLASSIFIED AS
BEING IN SEVERE DROUGHT EXCEPT FOR SMALL PORTIONS OF EASTERN AND
SOUTHERN NEVADA AND EASTERN SAN BERNARDINO COUNTY THAT WERE
CLASSIFIED AS HAVING MODERATE 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 COMING
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.

8/ LONG RANGE WEATHER OUTLOOK FOR NEVADA AND EASTERN CALIFORNIA...
THE OUTLOOK FOR THE REMAINDER OF APRIL...IS FOR BELOW NORMAL
PRECIPITATION FOR EASTERN AND SOUTHERN NEVADA ALONG WITH INYO AND
SAN BERNARDINO COUNTIES IN EASTERN CALIFORNIA...AND EQUAL CHANCES
FOR ABOVE...NEAR AND BELOW NORMAL PRECIPITATION FOR WESTERN AND
NORTHERN NEVADA AND EASTERN CALIFORNIA FROM MONO COUNTY TO THE
OREGON BORDER. TEMPERATURES ARE EXPECTED TO BE ABOVE AVERAGE FOR ALL
OF NEVADA AND EASTERN CALIFORNIA.

THE LONG RANGE OUTLOOK FOR THE MONTHS OF MAY THROUGH JULY IS FOR
ABOVE NORMAL TEMPERATURES FOR ALL OF NEVADA AND EASTERN CALIFORNIA.
THERE IS AN EQUAL CHANCE OF ABOVE...NEAR AND BELOW NORMAL
PRECIPITATION FOR ALL OF EASTERN CALIFORNIA AND NEVADA EXCEPT FAR
NORTHEAST CALIFORNIA WHERE BELOW AVERAGE PRECIPITATION IS EXPECTED.

9/ 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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