Areal Flood Advisory 67, NWS Philadelphia/Mount Holly

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
245 PM EDT FRI JUN 28 2013

.SYNOPSIS...
A STRENGTHENING AREA OF LOW PRESSURE WILL LIFT NORTHWARD INTO
SOUTHEASTERN CANADA THROUGH TODAY. THE ASSOCIATED COLD FRONT WILL
TEND TO STALL NEAR THE COAST INTO THE WEEKEND, AS AN UPPER LEVEL
LOW MOVES OVER THE MIDWEST AND GREAT LAKES. A BERMUDA HIGH PRESSURE
SYSTEM MAY TRY TO BUILD BACK TOWARD THE EAST COAST NEXT WEEK, AS A
FRONTAL BOUNDARY NEAR OUR AREA GRADUALLY DISSIPATES.

&&

.NEAR TERM /THROUGH TONIGHT/...
SEL7 IN PROGRESS. PLEASE FOLLOW ALL MOUNT HOLLY WARNINGS...STATEMENTS
LOCAL STORM REPORTS AND PUBLIC INFORMATION STATEMENTS. PLEASE SEND
ANY DAMAGE REPORTS OR RAINFALL UNUSUAL FLOODING TO REPORTS TO THE
NWS VIA FACEBOOK...OR OTHER CHANNELS NORMALLY USED TO COMMUNICATE
WITH OUR OFFICE.

REMAINDER OF TODAY... WE THINK THE PRIMARY EVENT WILL BE DELMARVA...
BASICALLY PHL AND JUST SOUTH.

THE PRIMARY BAND OF STG-ISOLATED SVR TSTMS DEVELOP IN S CENTRAL
PA SWD TO MD DURING MID OR LATE AFTN AND QUICKLY ADVECT - DEVELOP
EWD INTO OUR AREA. THIS IS PER TRADITIONAL MODEL PLAN VIEW MASS
FIELDS INDICATING KI POPPING UP TO 35C WITH TT NEAR 48C LATE
TODAY. THESE STORMS WILL HAVE ABOUT 1400J ML CAPE TO WORK WITH
MUCH GREATER 0-6KM BULK SHEAR ARRIVING LATE IN THE DAY...35-45 KT
E PA DELMARVA. THE THINKING FROM OUR SHIFT AND THE PRIOR SHIFT...
FOCUS ON DELMARVA FOR WIND DAMAGE BETWEEN ROUGHLY 4 PM AND 10 PM.

THE PWAT WILL BE DOWN NEAR 1.7 INCHES TODAY... LESS THAN YDY BUT
STILL AMPLE FOR 1 HOUR RAINFALL OF AT LEAST 1.7 INCHES SHOULD
TSTMS REMAIN OVER AN AREA FOR 1 HOUR.

HIGHS IN THE UPPER 80S WITH GRADIENT WIND SW G 20 KT THIS AFTN
WITH MIXED CLOUDS AND SUN...PROBABLY MORE CLOUD COVER THAN YDY.

1 HR FFG AFTER YDYS RAINS ARE NOW IN THE 1.4-1.8 INCH RANGE FOR NW
CHESTER...CENTRAL MONTGOMERY...PHL COUNTY IN PA...NW CAMDEN...CENTRAL
BURLINGTON...MERCER...WARREN AND MORRIS COUNTIES IN NJ NEWD.

NO FFA. FFW...SVR AND SMW'S WBIS AS NEED.

TONIGHT...SHOWERS AND TSTMS DIMINISH SEWD DURING THE NIGHT WITH THE BIGGEST
STORMS OVER DELMARVA. THEN FAIR OVERNIGHT WITH HAZE AND HUMIDITY. ABOVE
NORMAL TEMPS.

ONE CAVEAT...SOME OF OUR GUIDANCE IS TRYING TO DEVELOP BACK EDGE
OF SHOWERS AND CLOUDS NEWD FROM DELMARVA ALONG THE COAST
OVERNIGHT. ATTM WE OPTED FOR A DRIER EASTWARD SOLUTION. NEEDS
REEVALUATION ON THE EVENING SHIFTS.

NO FOG IN THE FCST ATTM SINCE I WAS WRONG ON ITS EXPECTATION EARLY
THIS MORNING AND ITS JUST A SUMMER HUMID AIRMASS WITH SHORT NIGHTS.

AS FOR TEMPERATURES, MOSTLY AN EVEN BLEND OF THE GFS/NAM MOS WAS
USED. THE THINKING IS THESE TEMPS MAY BE 1-2F TOO COOL TONIGHT.

&&

.SHORT TERM /SATURDAY/...
SATURDAY...SHOULD BE BY AND LARGE RAINFREE OVER MOST OF THE AREA
WITH THE EXCEPTION POSSIBLY OF THE COAST. DO NOT HAVE THUNDER IN
THE FCST DUE TO LOWER DEWPOINTS...MUCH LESS MLCAPE. INSTABILITY IS
MARGINAL. ITS POSSIBLE WE'LL NEED TO MIX IN SOME THUNDER ALONG THE
COAST DURING THE AFTN BUT ATTM...NOT CONFIDENT OF ANY SHOWERS.

50 50 BLENDED 12Z/28 GFS/NAM MOS GUIDANCE FOR TEMPS/DEWS/WINDS.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
AN AREA OF LOW PRESSURE WILL MOVE INTO SOUTHEASTERN CANADA BY
SATURDAY WHILE ITS ASSOCIATED COLD FRONT STALLS ACROSS THE EAST
COAST. A CLOSED LOW ALOFT IS EXPECTED TO OPEN UP INTO A TROUGH AS
IT MOVES INTO SOUTHEASTERN CANADA ON SATURDAY, THEN DEVELOP INTO A
LONG WAVE TROUGH AND EXTEND FROM EASTERN CANADA, THROUGH THE GREAT
LAKES AND INTO THE DEEP SOUTH OVER THE WEEKEND INTO EARLY NEXT
WEEK. THIS WILL KEEP MULTIPLE SHORT WAVE/VORTICITY IMPULSES MOVING
ACROSS OUR AREA THROUGH THE PERIOD. THIS, COMBINED WITH THE
PROXIMITY OF THE FRONTAL BOUNDARY WILL KEEP A CHANCE OF
SHOWERS/THUNDERSTORMS IN THE FORECAST EACH DAY. MUCH OF THE STEADY
PRECIPITATION MAY REMAIN OFFSHORE OVER THE WEEKEND AS THE FRONT
REMAINS RIGHT ALONG THE COAST. HOWEVER, THIS COULD CHANGE AS WE
MOVE INTO THE EARLY PART OF NEXT WEEK.

A BERMUDA HIGH PRESSURE TO OUR EAST OVER THE ATLANTIC IS FORECAST TO
BEGIN PUSHING BACK WESTWARD EARLY NEXT WEEK INTO THE MIDDLE OF THE
WEEK. THIS WILL HELP EITHER PUSH THE FRONTAL BOUNDARY BACK TO OUR
WEST, OR HELP IT WASH OUT OVER THE AREA. A CLOSED LOW ALOFT MAY
ONCE AGAIN DEVELOP ACROSS THE CENTRAL PORTION OF THE COUNTRY,
WHILE RIDGING DEVELOPS JUST OFFSHORE OF THE ATLANTIC COAST. ANY
SHORT WAVE/VORTICITY IMPULSES COULD HELP CREATE SHOWERS/THUNDERSTORMS
ACROSS THE AREA THROUGH THE MIDDLE OF THE WEEK, HENCE WE KEEP A
CHANCE OF SHOWERS/THUNDERSTORMS IN THE FORECAST INTO THE MIDDLE OF
NEXT WEEK. MONDAY MAY HAVE THE BEST CHANCE FOR STEADY PRECIPITATION
AS THE FRONTAL BOUNDARY BEGINS TO PUSH BACK WESTWARD BEFORE IT
BEGINS TO WASH OUT TO OUR WEST. WITH WARM, MOIST AIRMASS REMAINING
ACROSS THE AREA, THERE WILL BE INSTABILITY EACH DAY. IN ADDITION,
PW VALUES WILL REMAIN AROUND 1.5-2 INCHES. THEREFORE, EACH DAY
THERE WILL BE THE POTENTIAL FOR STRONG THUNDERSTORMS WITH HEAVY
RAIN.

WITH A GENERAL SOUTHWEST FLOW ACROSS THE AREA AND THICKNESSES
REMAINING FAIRLY STEADY, TEMPERATURES THROUGH THE EXTENDED ARE NOT
EXPECTED TO RISE SHARPLY. THEREFORE, HIGH TEMPERATURES ARE FORECAST
TO BE FAIRLY CLOSE TO NORMAL OR A COUPLE OF DEGREES ABOVE, ALTHOUGH
LOW TEMPERATURES MAY BE A FEW DEGREES ABOVE NORMAL.

&&

.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

REMAINDER OF TODAY...SCT-BKN CLOUDS AOA 4000 FT THIS AFTN WITH SW G
20 KT. WINDS HAVE BRIEFLY BACKED A LITTLE MORE THAN EXPECTED IN MY
18Z TAF. WILL MONITOR AT 19Z FOR A POSSIBLE MORE SLY CONVERGENT
FLOW AHEAD OF THE TSTMS. BRIEF IFR VSBY TSTMS IN THE TAFS WHERE
MOST CONFIDENT ALONG WITH GUSTS. HIGH CONFIDENCE FOR TSTM EVENT
KPHL AREA BETWEEN 20Z-24Z....GUST IS 34 KT BUT NOT IMPOSSIBLE TO
SEE G45KT KPHL KILG. PLEASE MONITOR STORM DEVELOPMENT AND TAF UPDATES.

TONIGHT...AREAS OF SUB-VFR MAINLY DUE TO SHOWERS AND THUNDERSTORMS,
WHICH ARE ANTICIPATED TO WEAKEN DURING THE EVENING HOURS.
OTHERWISE, MOSTLY VFR ALTHOUGH SOME LOCAL FOG MAY DEVELOP
ESPECIALLY LATE. SOUTHWEST WINDS DIMINISHING TO NEAR 5 KNOTS.

SATURDAY...GENERALLY VFR SCT-BKN CLOUDS AOA 4000 FT EXCEPT POSSIBLE
MVFR HAZE TIL 14Z. LOW CONFIDENCE ON FCSTG ANY AFTN SHOWERS...AND
HAVE THESE RESTRICTED MAINLY TO THE COAST AND POCONOS.

OUTLOOK...
SATURDAY NIGHT THROUGH TUESDAY...GENERALLY VFR WITH PERIODS OF
MVFR/IFR POSSIBLE EACH DAY WITH SHOWERS AND THUNDERSTORMS AND
MORNING LOW CLOUDS/FOG. SUNDAY NIGHT INTO MONDAY MAY HAVE THE BEST
CHANCE FOR LONGER DURATION OF LOWER CONDITIONS.

&&

.MARINE...
ATLC SEAS SCA CONTINUES. ITS MARGINAL AND GFS WW3 GUIDANCE HAS
BEEN TOO HIGH AND STILL IS! WE TRIMMED THE 12Z/28 GFS WW3 GUIDANCE
AND SWELLS BY 1 FOOT THROUGH SATURDAY.

OUTLOOK...
THE SMALL CRAFT ADVISORY WAS EXTENDED INTO SATURDAY AS SEAS ARE
FORECAST TO REMAIN AROUND 5-6 FEET. WINDS MAY ALSO GUST AROUND 20-25
KNOTS. WITH HIGH PRESSURE TO OUR EAST AND A COLD FRONT STALLED NEAR
THE COAST, SOUTH-SOUTHWEST WINDS WILL CONTINUE ACROSS THE WATERS.
THIS WILL LIKELY KEEP SEAS AROUND 5-6 FEET THROUGH THE PERIOD AND
WINDS COULD GUST AROUND 20-25 KNOTS AS WELL.

&&

.RIP CURRENTS...
THERE IS A MODERATE RISK OF DANGEROUS RIP CURRENTS FOR THE NEW
JERSEY AND DELAWARE COASTS TODAY INTO TONIGHT. THIS IS BASED MAINLY
ON SOME HIGHER SURF AND ALSO A SOMEWHAT LONGER PERIOD SWELL
CONTRIBUTION.

&&

.CLIMATE...
WARMER THAN NORMAL DAILY TEMPS FOR AT LEAST THE NEXT 10-14 DAYS...
(JULY 10TH FOR NOW) AS A PERSISTENT HUMID SSW SFC FLOW PREVAILS...
PER 00Z/28 NAEFS AND 00Z/28 RMOP. A STAUNCH WESTERN ATLC RIDGE
DEVELOPS AND BUILDS WESTWARD AND THEN MAY EMERGE OVER THE SE USA
BY JULY 8TH...WHICH IF OCCURS...RETURNS 90F HEAT TO OUR AREA
AS THE SSW FLOW TURNS MORE SW OR WSW.

EC AND GFS MODEL TEMP GUIDANCE IS IN AGREEMENT THE NEXT 7 DAYS
WITH TEMPS AVG'G 2 TO 6 DEGS ABOVE NORMAL ON A DAILY BASIS...THE
GREATEST DEPARTURES OCCURRING WITH NIGHTTIME LOWS BEING SIGNIFICANTLY
ON THE WARM SIDE OF NORMAL...AVERAGING ABOUT 5 DEGS WARMER THAN
NORMAL NIGHTLY. THIS IS THE RESPONSE TO HIGH DEWPOINTS PREVENTING
DECENT RADIATIONAL COOLING.

JUNE TEMPERATURES WILL AVERAGE ABOVE NORMAL FOR ALL STATIONS ON
THE ORDER OF GENERALLY 1 TO 2 DEGREES...MAYBE MORE THAN 2 DEGS
ABOVE NORMAL AT KRDG AND KGED.

AS OF 6/28 PHL SPECIFICALLY PROJECTS 74.6 OR 1.4 ABOVE NORMAL. THE
JUNE 1981-2010 AVG IS 73.2.

JUNE RAINFALL BELOW..

AS OF THE THE 28TH 1 AM EDT...

KILG ALREADY RECORD MONTHLY RFALL AT 10.66

KPHL RANKED #2 AT 9.37 INCHES...CLOSING IN ON THE 10.06 JUNE 1998
RECORD.

KACY STILL RANKED #3 AT 7.20 BEHIND THE 7.57 IN 1935 AND RECORD JUNE
TOTAL OF 8.45 IN 1920.

KABE NOW RANKED 6TH WETTEST JUNE AT 6.81 INCHES. THE MONTHLY
RECORD IS 10.51 IN 1938.

KGED 11.65
KTTN 9.89  RECORD 13.8 1996
KMPO 8.80  RECORD 12.10 2006
KRDG 5.83  RECORD 15.73 1972 (AGNES)

RECORD DAILY RAINFALLS TODAY...ACY PHL ABE AND MPO ALL MORE THAN 2
INCHES AND NOT LISTED AS THESE SEEM OUT OF REACH.

KILG 1.85 2006
KTTN 1.95 2006
KGED 0.75 2006 AND
KRDG 1.44 1946

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR ANZ450>455.

&&

SYNOPSIS...GORSE
NEAR TERM...DRAG 244
SHORT TERM...DRAG 244
LONG TERM...ROBERTSON
AVIATION...DRAG/ROBERTSON 244
MARINE...DRAG/ROBERTSON 244
RIP CURRENTS...
CLIMATE...

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
225 PM EDT FRI JUN 28 2013

NJZ001-007>010-012-PAZ054-055-062-291830-
SUSSEX-WARREN-MORRIS-HUNTERDON-SOMERSET-MIDDLESEX-CARBON-MONROE-
NORTHAMPTON-
225 PM EDT FRI JUN 28 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHERN NEW
JERSEY...NORTHWEST NEW JERSEY...EAST CENTRAL PENNSYLVANIA AND
NORTHEAST PENNSYLVANIA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

SOME SHOWERS AND THUNDERSTORMS THIS AFTERNOON AND THIS EVENING MAY
PRODUCE STRONG WINDS AND HEAVY RAIN.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.

SHOWERS AND THUNDERSTORMS ARE POSSIBLE EACH DAY FROM SUNDAY
THROUGH NEXT WEEK, WHICH COULD CONTAIN GUSTY WINDS AND HEAVY
RAIN.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

DEZ001>003-MDZ008-012-015-019-020-NJZ013-015>023-027-PAZ060-061-070-
071-101>106-291830-
NEW CASTLE-KENT-INLAND SUSSEX-CECIL-KENT MD-QUEEN ANNES-TALBOT-
CAROLINE-WESTERN MONMOUTH-MERCER-SALEM-GLOUCESTER-CAMDEN-
NORTHWESTERN BURLINGTON-OCEAN-CUMBERLAND-ATLANTIC-CAPE MAY-
SOUTHEASTERN BURLINGTON-BERKS-LEHIGH-DELAWARE-PHILADELPHIA-
WESTERN CHESTER-EASTERN CHESTER-WESTERN MONTGOMERY-
EASTERN MONTGOMERY-UPPER BUCKS-LOWER BUCKS-
225 PM EDT FRI JUN 28 2013

...SEVERE THUNDERSTORM WATCH 387 IN EFFECT UNTIL 9 PM EDT THIS
EVENING...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL DELAWARE...NORTHERN
DELAWARE...SOUTHERN DELAWARE...NORTHEAST MARYLAND...CENTRAL NEW
JERSEY...SOUTHERN NEW JERSEY...EAST CENTRAL PENNSYLVANIA AND
SOUTHEAST PENNSYLVANIA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE
INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS.

   SEVERE THUNDERSTORM WATCH.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.

SHOWERS AND THUNDERSTORMS ARE POSSIBLE EACH DAY FROM SUNDAY INTO
NEXT WEEK, WHICH COULD CONTAIN GUSTY WINDS AND HEAVY RAIN.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

DEZ004-NJZ014-024>026-291830-
DELAWARE BEACHES-EASTERN MONMOUTH-ATLANTIC COASTAL CAPE MAY-
COASTAL ATLANTIC-COASTAL OCEAN-
225 PM EDT FRI JUN 28 2013

...SEVERE THUNDERSTORM WATCH 387 IN EFFECT UNTIL 9 PM EDT THIS
EVENING...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHERN DELAWARE...CENTRAL
NEW JERSEY AND SOUTHERN NEW JERSEY.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE
INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS.

   SEVERE THUNDERSTORM WATCH.

THERE IS A MODERATE RISK OF DANGEROUS RIP CURRENTS.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.

SHOWERS AND THUNDERSTORMS ARE POSSIBLE EACH DAY FROM SUNDAY
THROUGH NEXT WEEK, WHICH COULD CONTAIN GUSTY WINDS AND HEAVY
RAIN.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

ANZ430-431-450>455-291830-
DELAWARE BAY WATERS NORTH OF EAST POINT NJ TO SLAUGHTER BEACH DE-
DELAWARE BAY WATERS SOUTH OF EAST POINT NJ TO SLAUGHTER BEACH DE-
COASTAL WATERS FROM SANDY HOOK TO MANASQUAN INLET NJ OUT 20 NM-
COASTAL WATERS FROM MANASQUAN INLET TO LITTLE EGG INLET NJ OUT 20 NM-
COASTAL WATERS FROM LITTLE EGG INLET TO GREAT EGG INLET NJ OUT 20 NM-
COASTAL WATERS FROM GREAT EGG INLET TO CAPE MAY NJ OUT 20 NM-
COASTAL WATERS FROM CAPE MAY NJ TO CAPE HENLOPEN DE OUT 20 NM-
COASTAL WATERS FROM CAPE HENLOPEN TO FENWICK ISLAND DE OUT 20 NM-
225 PM EDT FRI JUN 28 2013

...SEVERE THUNDERSTORM WATCH 387 IN EFFECT UNTIL 9 PM EDT THIS
EVENING...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR ATLANTIC COASTAL WATERS AND
DELAWARE BAY WATERS.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE
INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS.

   SEVERE THUNDERSTORM WATCH.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.

THUNDERSTORMS WITH STRONG WIND GUSTS ARE POSSIBLE MAINLY EACH
AFTERNOON OR EVENING FROM SUNDAY INTO NEXT WEEK.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

..UPDATE FOR THE NEW SEVERE THUNDERSTORM WATCH..

PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
113 PM EDT FRI JUN 28 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0800 PM     FLASH FLOOD      EWING                   40.27N  74.80W
06/27/2013                   MERCER             NJ   TRAINED SPOTTER

            NUMEROUS REPORTS OF FLASH FLOODING THROUGHOUT THE
            COUNTY.

0800 PM     FLOOD            WARWICK                 40.17N  75.78W
06/27/2013                   CHESTER            PA   LAW ENFORCEMENT

            MEARNS ROAD NORTH OF BRISTOL ROAD AND CREEK ROAD CLOSED
            DUE TO FLOODING.

0900 PM     FLASH FLOOD      BRANCHBURG              40.55N  74.72W
06/27/2013                   SOMERSET           NJ   TRAINED SPOTTER

            CHAMBERS BROOK FLOODED.

&&

EVENT NUMBER PHI1300207 PHI1300208 PHI1300209

GAINES