National Weather Service Text Product Display

Flood Potential Outlook
Issued by NWS Mt. Holly, NJ
Versions: 1
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FGUS71 KPHI 211953
ESFPHI
DEC001-003-005-MDC011-015-029-035-041-NJC001-005-007-009-011-015-
019-021-023-025-027-029-033-035-037-041-PAC011-017-025-029-045-
077-089-091-095-101-042130-

WINTER/SPRING FLOOD POTENTIAL OUTLOOK
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
350 PM EDT THU MAR 21 2013

WINTER/SPRING FLOOD POTENTIAL OUTLOOK...NUMBER 6

THIS IS THE SIXTH IN A SERIES OF ANNUAL WINTER/SPRING FLOOD
POTENTIAL STATEMENTS INTENDED TO PROVIDE INSIGHT INTO THE LIKELIHOOD
OF RIVER FLOODING (NOT FLASH FLOODING) OVER THE MIDDLE/LOWER
DELAWARE, LEHIGH, SCHUYLKILL, PASSAIC AND RARITAN RIVER BASINS.
THESE STATEMENTS WILL PROVIDE INFORMATION ON FLOOD THREAT CONDITIONS
SUCH AS RECENT PRECIPITATION, SOIL MOISTURE, SNOW COVER AND ITS
WATER EQUIVALENT, RIVER ICE CONDITIONS, STREAMFLOW, FUTURE
PRECIPITATION AND OTHERS.

IN THE MID-ATLANTIC REGION, HEAVY RAINFALL IS THE PRIMARY FACTOR
WHICH LEADS TO RIVER FLOODING. IT IS IMPORTANT TO NOTE THAT HEAVY
RAINFALL CAN RAPIDLY CAUSE RIVER FLOODING ANY TIME OF YEAR, EVEN
WHEN THE OVERALL RIVER FLOOD POTENTIAL IS CONSIDERED TO BE LOW.

THIS OUTLOOK IS VALID FOR THE TWO-WEEK PERIOD, MARCH 21 TO APRIL 4,
2013.

IN THE MOUNT HOLLY, NEW JERSEY HYDROLOGIC SERVICE AREA (HSA), THE
RIVER FLOOD POTENTIAL IS NORMAL.

NOTE - FOR THE HEADWATERS OF THE DELAWARE RIVER, SEE THE STATEMENT
(FGUS71 KBGM ESFBGM) FROM OUR BINGHAMTON (BGM), NEW YORK OFFICE.

CURRENT FLOODING - NONE.

RECENT PRECIPITATION - SLIGHTLY BELOW NORMAL TO NORMAL. BETWEEN 2.0
AND 4.0 INCHES OF LIQUID HAS BEEN RECORDED OVER THE LAST 30 DAYS.
PRECIPITATION DEPARTURE MAPS CAN BE FOUND AT
WWW.ERH.NOAA.GOV/ER/MARFC.

SNOW COVER - NORMAL. CURRENTLY WITHIN THE HSA, THERE IS SNOW ON THE
GROUND ACROSS PORTIONS OF THE DELAWARE, LEHIGH, UPPER SCHUYLKILL,
AND PASSAIC BASINS, BUT WATER EQUIVALENT VALUES ARE LESS THAN 1.0
INCH. THIS IS NOT ENOUGH SNOW TO CAUSE RIVER FLOODING UNLESS
SIGNIFICANT RAINFALL ACCOMPANIES THE SNOWMELT. SNOW DEPTH AND
BASIN-AVERAGE WATER EQUIVALENT ESTIMATES CAN BE FOUND AT
WWW.ERH.NOAA.GOV/ER/MARFC OR WWW.NOHRSC.NWS.GOV.

RIVER ICE - NORMAL. NO SIGNIFICANT RIVER ICE EXISTS WITHIN THE HSA.

STREAMFLOW - NORMAL. REAL TIME WATER DATA IS AVAILABLE FROM THE
UNITED STATES GEOLOGICAL SURVEY BY VISITING HTTP://WATER.USGS.GOV.

SOIL MOISTURE - NORMAL. SOIL MOISTURE MONITORING CHARTS FROM
NOAA`S CLIMATE PREDICTION CENTER CAN BE FOUND AT
WWW.CPC.NCEP.NOAA.GOV/PRODUCTS/SOILMST_MONITORING/US/SOILMST/SOILMST.
SHTML AS WELL AS WWW.DROUGHT.GOV.

GROUND WATER - MONITORING WELLS INDICATE THAT CURRENT GROUND WATER
LEVELS ACROSS THE REGION ARE NORMAL.

RESERVOIR CONDITIONS - ALL WATER SUPPLY AND FLOOD CONTROL RESERVOIRS
IN THE AREA ARE AROUND NORMAL.

FUTURE WEATHER CONDITIONS - A STORM SYSTEM WILL APPROACH AND MOVE
THROUGH THE REGION SUNDAY-MONDAY, MARCH 18-19. PRESENTLY THIS SYSTEM
LOOKS COLD FOR EARLY SPRING, WHICH SUGGESTS THAT SOME OF THE
PRECIPITATION COULD BE SNOW OR MIXED PRECIPITATION. BEYOND THIS
SYSTEM, DRIER BUT CONTINUED UNSEASONABLY COLD WEATHER SEEMS LIKELY.

THE 8 TO 14 DAY OUTLOOK CALLS FOR BELOW NORMAL TEMPERATURES AND
PRECIPITATION. PLEASE VISIT WWW.CPC.NCEP.NOAA.GOV.

ADVANCED HYDROLOGIC PREDICTION SERVICE (AHPS) - NORMAL FOR THIS TIME
OF YEAR. ANOTHER TOOL USED TO ASSESS THE POTENTIAL FOR WINTER/SPRING
FLOODING IS CALLED AHPS, ADVANCED HYDROLOGIC PREDICTION SERVICE. ONE
COMPONENT OF AHPS IS THE GENERATION OF PROBABILISTIC RIVER FORECASTS
BASED ON CURRENT BASIN CONDITIONS (RIVER LEVELS, SOIL MOISTURE,
EXTENT AND CONDITION OF SNOWPACK) ALONG WITH 50 YEARS OF HISTORIC
TEMPERATURE AND PRECIPITATION DATA.

FOR THIS OUTLOOK, THE AHPS TECHNIQUE HAS BEEN APPLIED TO THE
DELAWARE, PASSAIC AND RARITAN RIVER SYSTEMS. FOURTEEN DAY
PROBABILISTIC FORECASTS GENERATED FOR THESE BASINS SHOW THAT THE
LIKELIHOOD OF FLOODING IS NORMAL COMPARED TO WHAT HAS BEEN
HISTORICALLY OBSERVED.

IT SHOULD BE NOTED THAT AHPS PROBABILISTIC FORECASTS DO NOT TAKE INTO
ACCOUNT FUTURE PRECIPITATION.

SUMMARY - TAKING ALL OF THE INCLUDED VARIABLES INTO CONSIDERATION,
THE OVERALL FLOOD POTENTIAL OVER THE NEXT TWO WEEKS IS NORMAL.

THE NEXT WINTER/SPRING FLOOD OUTLOOK WILL BE ISSUED IN APPROXIMATELY
TWO WEEKS.

FOR COMPLETE WEATHER INFORMATION, VISIT OUR WEB SITE AT:
WWW.WEATHER.GOV/PHI

$$

SUMMARY/OVERVIEW OF FLOOD POTENTIAL THROUGH APRIL 4, 2013:

OVERALL FLOOD POTENTIAL...NORMAL
CURRENT FLOODING...NONE
RECENT PRECIPITATION...SLIGHTLY BELOW NORMAL TO NORMAL
SNOW COVER...NORMAL
RIVER ICE...NORMAL
STREAMFLOW...NORMAL
SOIL MOISTURE...NORMAL
GROUND WATER...NORMAL
RESERVOIR CONDITIONS...NORMAL
AHPS...NORMAL

$$

KRUZDLO
National Weather Service Weather Forecast Office
