Flood Potential Outlook
Issued by NWS Raleigh/Durham, NC

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123-125-127-135-145-151-153-163-165-167-181-183-185-191-195-051600-

WINTER/SPRING FLOOD POTENTIAL OUTLOOK
NATIONAL WEATHER SERVICE RALEIGH NC
400 AM EST SAT FEB 21 2015

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

...THE RISK OF RIVER FLOODING ACROSS CENTRAL NORTH CAROLINA THROUGH
SPRING IS NEAR NORMAL.....

PRECIPITATION SUMMARY

PRECIPITATION ACROSS CENTRAL NORTH CAROLINA FROM FALL INTO MID
FEBRUARY CONTINUES TO SHOW A MARKED GRADIENT RANGING FROM BELOW
NORMAL (AS LITTLE AS 75% OF NORMAL) ACROSS THE WEST IN THE
YADKIN/PEE DEE RIVER BASIN TO AS MUCH AS 110% ABOVE NORMAL ACROSS
THE EAST (GENERALLY THE MID TO LOWER REACHES OF THE CAPE
FEAR...NEUSE...AND TAR RIVER BASINS).

THE RAINFALL DEFICIT IN THE YADKIN RIVER BASIN NOTED ABOVE IS THE
PRIMARY DRIVER FOR MAINTAINING ABNORMALLY DRY DROUGHT CONDITIONS IN
THE NORTHWEST PIEDMONT...WHERE THE DEFICIT SINCE OCTOBER HOVERS FROM
70 TO 80 PERCENT OF NORMAL IN 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
  FEB TO DATE   1.63/-0.62     1.45/-0.59     1.46/-0.52

  TOTALS       15.91/ 0.72    11.04/-3.28    14.20/ 0.29

  % OF NORMAL      105             77            102


                            ACTUAL   NORMAL  DEPARTURE  PERCENT
                             PCPN     PCPN   FROM NORM  OF NORM

RALEIGH-DURHAM INTERNATIONAL AIRPORT (RDU)

 LAST   7 DAYS   02/13/2015   0.67    0.82     -0.15       82%
 LAST  14 DAYS   02/06/2015   1.24    1.57     -0.33       79%
 LAST  30 DAYS   01/21/2015   2.71    3.36     -0.65       81%
 LAST  90 DAYS   11/22/2014  12.44    9.63      2.81      129%
 LAST 180 DAYS   08/24/2014  21.89   20.61      1.28      106%
 LAST 365 DAYS   02/20/2014  55.67   43.34     12.33      128%

PIEDMONT TRIAD INTERNATIONAL AIRPORT (GSO)

 LAST   7 DAYS   02/13/2015   0.48    0.76     -0.28       63%
 LAST  14 DAYS   02/06/2015   1.07    1.43     -0.36       75%
 LAST  30 DAYS   01/21/2015   2.36    2.98     -0.62       79%
 LAST  90 DAYS   11/22/2014   7.64    8.90     -1.26       86%
 LAST 180 DAYS   08/24/2014  13.97   19.44     -5.47       72%
 LAST 365 DAYS   02/20/2014  33.84   42.20     -8.36       80%

FAYETTEVILLE AIRPORT (FAY)

 LAST   7 DAYS   02/13/2015   0.65    0.78     -0.13       83%
 LAST  14 DAYS   02/06/2015   0.94    1.42     -0.48       66%
 LAST  30 DAYS   01/21/2015   2.59    3.24     -0.65       80%
 LAST  90 DAYS   11/22/2014  12.60    8.71      3.89      145%
 LAST 180 DAYS   08/24/2014  21.06   19.47      1.59      108%
 LAST 365 DAYS   02/20/2014  41.55   44.46     -2.91       93%

STREAMFLOW AND LAKE LEVELS

IN THE SHORT TERM...THERE HAVE BEEN SEVERAL SIGNIFICANT (>0.25
INCHES) WIDESPREAD PRECIPITATION EVENTS ACROSS CENTRAL NORTH
CAROLINA IN FEBRUARY. CUMULATIVELY...THESE EVENTS STILL DO NOT ADD
UP TO NORMAL PRECIPITATION...ABOUT A HALF INCH BELOW NORMAL...BUT
TEMPERATURES HAVE BEEN ABOUT 10 DEGREES BELOW NORMAL TO OFFSET THE
DEFICIT WITH REDUCED EVAPORATION. THE NET RESULT HAS BEEN TO
MAINTAIN NEAR NORMAL FLOWS IN EASTERN RIVERS...WHILE A FEW STREAMS
IN THE WEST (WHICH WERE ALREADY BELOW NORMAL) REMAIN BELOW THE 25TH
PERCENTILE FOR THIS TIME OF YEAR.

THE LARGER WATER SUPPLY RESERVOIRS LOCATED IN CENTRAL NC...FALLS
LAKE AND LAKE JORDAN...BOTH OPERATED BY THE U.S. ARMY CORPS OF
ENGINEERS...ARE BOTH SLIGHTLY ABOVE THEIR TARGET ELEVATIONS.

SHORT TERM FORECAST

NO SIGNIFICANT PRECIPITATION IS EXPECTED THROUGH LATE THIS MONTH. IT
IS ESTIMATED THAT AN EVENT PRODUCING AT LEAST 2 INCHES WOULD BE
NEEDED TO PRODUCE RIVER FLOODING OF CONSEQUENCE. AS SUCH...THE
CHANCE FOR RIVER FLOODING IS CLASSIFIED AS NEAR NORMAL HEADING INTO
LATE FEBRUARY.

LONG TERM PRECIPITATION OUTLOOK

CLIMATOLOGICALLY...THE FREQUENCY OF RIVER FLOODING RISES WITH THE
APPROACH OF SPRING...PEAKING IN MARCH AND APRIL. AN ACTIVE SOUTHERN
STREAM IS EXPECTED THROUGH MARCH...WHICH WOULD INCREASE THE CHANCE
FOR SIGNIFICANT LOW PRESSURE SYSTEMS TO DEVELOP IN THE SOUTHEASTERN
UNITED STATES. HOWEVER...IT IS NOT POSSIBLE TO FORECAST IMPORTANT
DETAILS SUCH AS THE STRENGTH OF AN INDIVIDUAL SYSTEM OR THE
POSSIBILITY OF MORE THAN ONE SYSTEM IMPACTING THE AREA WITHIN A
RELATIVELY SHORT TIME FRAME. AS SUCH...THE LONGER RANGE CHANCE FOR
RIVER FLOODING IS CATEGORIZED AS NEAR NORMAL.

ADDITIONAL DETAILS 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. CONVERSELY...CONDITIONS IN THE WEST ARE DRY. THERE ARE NO
SYSTEMS IN THE SHORT RANGE CAPABLE OF PRODUCING ENOUGH PRECIPITATION
(>2 INCHES) TO CAUSE RIVER FLOODING OF ANY CONSEQUENCE. AS SUCH...
THE CHANCE FOR RIVER FLOODING THROUGH LATE-FEBRUARY IS CATEGORIZED
AS NEAR NORMAL.

THERE HAS BEEN A SHIFT TOWARDS A WETTER OUTLOOK FOR THE MONTH OF
MARCH. HOWEVER...THERE IS LITTLE CONFIDENCE IN FORECASTING SYSTEMS
WHICH COULD PRODUCE ENOUGH RAIN TO OVERCOME RELATIVELY DRY
ANTECEDENT MOISTURE CONDITIONS. THUS THE CHANCE FOR RIVER FLOODING
FROM LATE-FEBRUARY THROUGH APRIL IS ALSO CATEGORIZED AS NEAR NORMAL.

THE NEXT WINTER/SPRING FLOOD POTENTIAL OUTLOOK WILL BE ISSUED ON
MARCH 5TH.

MLM



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