Flood Potential Outlook
Issued by NWS Raleigh/Durham, NC

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FGUS72 KRAH 201251
ESFRAH
NCC001-007-037-051-057-063-065-067-069-077-081-083-085-093-101-105-
123-125-127-135-145-151-153-163-165-167-181-183-185-191-195-021600-

SPRING FLOOD POTENTIAL OUTLOOK
NATIONAL WEATHER SERVICE RALEIGH NC
235 PM EST THU MAR 19 2015

...SPRING FLOOD POTENTIAL OUTLOOK FOR CENTRAL NORTH CAROLINA...

...THE CHANCE OF RIVER FLOODING ACROSS CENTRAL NORTH CAROLINA FOR
THE REMAINDER OF MARCH IS NEAR NORMAL...
...THE CHANCE OF RIVER FLOODING FROM APRIL THROUGH THE REMAINDER OF
SPRING IS NORMAL TO SLIGHTLY ABOVE NORMAL...

PRECIPITATION SUMMARY

SHORT TERM RAINFALL HAS BEEN BELOW NORMAL OVER THE PAST TWO
WEEKS...RANGING FROM LESS THAN 50 PERCENT OF NORMAL IN THE SOUTHWEST
PIEDMONT (LOWER YADKIN/PEE DEE RIVER BASIN) TO ABOUT 90 PERCENT OF
NORMAL IN THE CENTRAL COASTAL PLAIN (CENTRAL NEUSE AND TAR RIVER
BASINS).

PRECIPITATION ACROSS CENTRAL NORTH CAROLINA FOR THE WATER YEAR
(OCTOBER 2014 TO PRESENT) CONTINUES TO SHOW A MARKED GRADIENT RANGING
FROM BELOW NORMAL (AS LITTLE AS 70% OF NORMAL) ACROSS THE WEST IN THE
YADKIN/PEE DEE RIVER BASIN TO AS MUCH AS 120% ABOVE NORMAL ACROSS
THE EAST (GENERALLY THE MID TO LOWER REACHES OF THE CAPE FEAR...
NEUSE...AND TAR RIVER BASINS).

THE LONG TERM RAINFALL DEFICIT (70 TO 80 PERCENT OF NORMAL) IN THE
YADKIN RIVER BASIN NOTED ABOVE IS THE PRIMARY DRIVER FOR MAINTAINING
ABNORMALLY DRY DROUGHT CONDITIONS (WWW.DROUGHT.GOV) IN NORTHWEST
PIEDMONT COUNTIES (FORSYTH...GUILFORD...AND DAVIDSON COUNTIES).

THE FOLLOWING TABLES SUMMARIZE PRECIPITATION AND MONTHLY DEFICITS.

               PRECIPITATION (INCHES)/DEPARTURE FROM NORMAL
               WATER YEAR (BEGINNING 1 OCTOBER 2014)TO DATE

    MONTH           RDU            GSO        FAYETTEVILLE
---------------------------------------------------------------------

  OCTOBER        2.18/-1.07     2.01/-1.12     1.31/-1.90
  NOVEMBER       3.78/ 0.66     3.33/ 0.22     2.84/ 0.07
  DECEMBER       4.97/ 1.90     2.21/-0.77     4.22/ 1.57
  JANUARY        3.35/-0.15     2.04/-1.02     4.37/ 1.07
  FEBRUARY       2.91/-0.32     2.64/-0.32     3.28/ 0.52
  MARCH TO DATE  2.16/-0.27     1.61/-0.55     1.62/-0.31

  TOTALS
  YEAR TO DATE   8.42/-0.74     6.29/-1.89     9.27/1.28
   % OF NORMAL      92              77            116
  WATER YEAR    19.35/ 0.75    13.84/-3.56    17.64/1.02
   % OF NORMAL      104             80            106


                            ACTUAL   NORMAL  DEPARTURE  PERCENT
                             PCPN     PCPN   FROM NORM  OF NORM

RALEIGH-DURHAM INTERNATIONAL AIRPORT (RDU)

 LAST   7 DAYS   03/12/2015   0.32    0.95     -0.63       34%
 LAST  14 DAYS   03/05/2015   1.40    1.91     -0.51       73%
 LAST  30 DAYS   02/17/2015   3.89    3.88      0.01      100%
 LAST  90 DAYS   12/19/2014  12.28   10.45      1.83      118%
 LAST 180 DAYS   09/20/2014  22.84   19.99      2.85      114%
 LAST 365 DAYS   03/19/2014  54.89   43.34     11.55      127%

PIEDMONT TRIAD INTERNATIONAL AIRPORT (GSO)

 LAST   7 DAYS   03/12/2015   0.33    0.85     -0.52       39%
 LAST  14 DAYS   03/05/2015   1.32    1.70     -0.38       78%
 LAST  30 DAYS   02/17/2015   2.86    3.52     -0.66       81%
 LAST  90 DAYS   12/19/2014   7.97    9.40     -1.43       85%
 LAST 180 DAYS   09/20/2014  14.23   18.75     -4.52       76%
 LAST 365 DAYS   03/19/2014  32.76   42.20     -9.44       78%

FAYETTEVILLE AIRPORT (FAY)

 LAST   7 DAYS   03/12/2015   1.00    0.77      0.23      130%
 LAST  14 DAYS   03/05/2015   1.40    1.51     -0.11       93%
 LAST  30 DAYS   02/17/2015   3.89    3.17      0.72      123%
 LAST  90 DAYS   12/19/2014  12.95    8.92      4.03      145%
 LAST 180 DAYS   09/20/2014  18.47   18.19      0.28      102%
 LAST 365 DAYS   03/19/2014  42.24   44.46     -2.22       95%


STREAMFLOW AND LAKE LEVELS

IN THE SHORT TERM...THERE HAVE BEEN THREE SIGNIFICANT (>0.25
INCHES) REASONABLY WIDESPREAD PRECIPITATION EVENTS ACROSS CENTRAL
NORTH CAROLINA THUS FAR IN MARCH. THE TOTAL RAIN FROM THESE EVENTS
WAS SLIGHTLY BELOW NORMAL FOR THE PERIOD...WITH A GENERAL NET RESULT
OF MAINTAINING HYDROLOGIC CONDITIONS AT NEAR NORMAL LEVELS.
STREAMFLOWS HAVE SHOWN A SHORT TERM FALLING TREND AND A NUMBER OF
STREAMS IN THE YADKIN/PEE DEE AND HAW RIVER BASINS ARE BELOW NORMAL
(LESS THAN THE 25TH PERCENTILE OF FLOWS FOR THIS TIME OF YEAR).
STREAMFLOWS FOR A LONGER TIME PERIOD (4 WEEKS)...HOWEVER...ARE IN
THE NORMAL RANGE ACROSS THE ENTIRE AREA.

THE LARGER WATER SUPPLY RESERVOIRS LOCATED IN CENTRAL NC...FALLS
LAKE AND LAKE JORDAN...BOTH OPERATED BY THE U.S. ARMY CORPS OF
ENGINEERS...BENEFITTED GREATLY FROM A WINTER STORM IN LATE FEBRUARY
AND THE SUBSEQUENT DELAYED INFLOWS. INFLOWS INTO THE LAKES WAS
GREATER THAN 150% OF NORMAL DURING EARLY MARCH...TAPERING OFF TO 50%
TO 60% OF NORMAL BY MID MONTH. BOTH LAKES ARE WITHIN A FEW TENTHS OF
A FOOT OF THEIR TARGET POOL...WHICH IS SUFFICIENT TO MAINTAIN
ADEQUATE PUBLIC WATER SUPPLIES THROUGH THE SUMMER.

SHORT TERM FORECAST

A LATE SEASON WINTER STORM IS EXPECTED TO PRODUCE AROUND A HALF INCH
OF WIDESPREAD RAIN OVER CENTRAL NORTH CAROLINA ON 3/19-20. IT IS
ESTIMATED THAN IT WOULD REQUIRE WIDESPREAD RAINFALL EXCEEDING 1.5
INCHES TO CAUSE RIVER FLOODING OF ANY CONSEQUENCE. AS THE NEXT
POTENTIALLY SIGNIFICANT RAIN EVENT IS NOT EXPECTED UNTIL LATE NEXT
WEEK...THE SHORT RANGE CHANCE FOR RIVER FLOODING IS CLASSIFIED AS
NEAR NORMAL HEADING INTO LATE MARCH.

LONG TERM PRECIPITATION OUTLOOK

CLIMATOLOGICALLY...MARCH AND APRIL ARE THE MONTHS OF PEAK FREQUENCY
FOR RIVER FLOODING OVER CENTRAL NORTH CAROLINA. THERE IS A 50-60%
CHANCE OF EL NINO CONDITIONS THROUGH THE REMAINDER OF 2015...WITH A
CORRESPONDING INCREASE IN THE PROBABILITY OF ENHANCED RAIN OVER THE
SOUTHEASTERN UNITED STATES. DEEP LAYER (0-200 CM) SOIL MOISTURE IS
NORMAL TO ABOVE NORMAL...AND CONSIDERING THE RECENT CHANGE IN THE
OUTLOOK FOR RAIN DUE TO THE LATEST ENSO FORECAST...THERE IS A NORMAL
TO SLIGHTLY ABOVE NORMAL CHANCE FOR RIVER FLOODING FROM APRIL
THROUGH THE END OF SPRING.

ADDITIONAL DETAILS AND DISCUSSION MAY BE FOUND AT THE CLIMATE
PREDICTION CENTER WEBSITE:

HTTP://WWW.CPC.NCEP.NOAA.GOV

IN SUMMARY...CURRENT CONDITIONS ARE RATHER WET ACROSS EASTERN NORTH
CAROLINA...WHILE CONDITIONS IN THE WEST ARE CONSIDERABLY DRIER.
THERE ARE NO SYSTEMS IN THE SHORT RANGE FORECAST LIKELY TO PRODUCE
ENOUGH PRECIPITATION (>1.5 INCHES) TO CAUSE RIVER FLOODING OF ANY
CONSEQUENCE. AS SUCH...THE CHANCE FOR RIVER FLOODING THROUGH LATE
MARCH IS CATEGORIZED AS NEAR NORMAL.

THERE HAS BEEN A SHIFT TOWARDS A WETTER OUTLOOK FOR LATE SPRING INTO
THE SUMMER DUE TO DEVELOPMENT OF A WEAK EL NINO. CONFIDENCE IN THIS
OUTLOOK IS NOT YET HIGH ENOUGH TO CONSIDER THE CHANCE OF RIVER
FLOODING TO BE SIGNIFICANTLY ABOVE NORMAL. THUS THE CHANCE FOR RIVER
FLOODING FOR APRIL THROUGH THE REMAINDER OF SPRING IS CATEGORIZED AS
NORMAL TO SLIGHTLY ABOVE NORMAL.

THE NEXT SPRING FLOOD POTENTIAL OUTLOOK WILL BE ISSUED ON APRIL 2ND.

MLM



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