Marine Weather Statement 27, NWS Philadelphia/Mount Holly

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1005AM EDT FRI AUG 24 2007

.SYNOPSIS...
A HIGH PRESSURE SYSTEM WILL SLIDE SLOWLY OFFSHORE TODAY. THE RETURN
FLOW AROUND IT FROM THE SOUTH WILL START PUMPING IN THE UNSEASONABLY
HOT AIR MASS OVER THE SOUTHEASTERN UNITED STATES INTO THE REGION,
ESPECIALLY SATURDAY. A COLD FRONT IS THEN FORECAST TO SLOWLY MOVE
SOUTHEAST FROM THE GREAT LAKES, CROSSING THE REGION VERY SLOWLY ON
SUNDAY BEFORE STALLING NEAR OR JUST SOUTH OF THE AREA ON MONDAY. A
HIGH PRESSURE SYSTEM SHOULD BUILD OVER NEW ENGLAND ON MONDAY AND
TUESDAY AND MOVE OFFSHORE ON WEDNESDAY. ANOTHER COLD FRONT WILL
APPROACH THE MIDDLE ATLANTIC STATES ON THURSDAY.

&&

.NEAR TERM /THROUGH 6 PM THIS EVENING/...
HAVE DROPPED THE ADVISORY FOR FOG AT THE COAST AND UPDATED TO BRING
ON THE SUNSHINE. LEFT HOME YESTERDAY ACTUALLY HAD TO PUT MY
SUNGLASSES ON. WHAT A NICE SITE TO SEE AGAIN. HOWEVER, WELL
PROBABLY BE CURSING THE SUN NEXT FEW DAYS AS THE MERCURY(DIGITAL
THERMOMETERS)RISE TOWARD THE UNCOMFORTABLE LEVELS. OTHERWISE MY
COLLEAUGE TFG HAS CAPTURED THE REMAINDER OF THE FORECAST QUITE
WELL.

STAY COOL

THE GFS CONTINUES TO SLIGHTLY OUTSHINE THE WRF-NMM WITH ITS INIT,
AND THE WRF-NMM IS SLIDING TWD IT WITH ITS MOST RECENT SOLN. WE WILL
THUS USE THE GFS SOLN PRETTY MUCH AS IS FOR TDY AND SAT AND
COMPROMISE BTWN THE GUID DATASETS FOR SUN. WE LIKE A SLIGHTLY SLOWER
CFP SOLN. THAT STUBBORN SERN RIDGE WILL BE TOUGH TO BUCKLE.

WE WILL BE ISSUING A DENSE FOG ADVY FOR OUR ERN NJ CTYS FOR THIS
MRNG. HAVING BEEN TAKING A LOOK AT TRAFFIC CAMS AND SFC OBS AND MORE
WDPSRD FOG AROUND ADVY CRIT IS OCRG NEAR THE COAST. CLOSER TO THE
PHL METRO AREA AND IN DELAMRVA ITS HIT AND MISS. WE WILL CONT TO
COVER IT WITH A SPS. THE FOG WAS MADE EASIER TO FORM BY THE CLOUDS
THAT CLEARED LATE YDA. IRONICALLY THE DEEPEST FCST MSTR ABV THE
GROUND IS FTHR NW TWD THE LEHIGH VLY AND POCONOS. BUT THERE REMAINS
A BIG DIF BTWN THE FCSTD THICKNESS OF THE MSTR TDY VS THE PAST FEW
DAYS. THE CLOUDS SHLD DISPT/BREAK. ETA MOS HAS RISEN CONSIDERABLY
FROM THE DEPTHS OF THE PAST COUPLE OF DAYS AND IS WI 5 DEG OF GFS
MOS IN MOST LOCALES. TDY WILL BE A GOOD LITMUS TEST TO SEE HOW MUCH
THE RECENT RAINS WILL SLOW THE RISE IN TEMPS. WE HAVE COMP BTWN THE
GUID DATASETS AS THE MRNG CLOUDS/FOG SHLD TAKE SOME OFF THE TOP.

THE CONVECTIVE QUES CONTS N AND W OF PHL FOR TDY. THE GFS HAS A MORE
DISCERNIBLE SHRT WV THAN THE WRF-NMM. IT IS ALSO INTERESTING THAT
THE CLOUDS MAY BREAK LAST WHERE THE GREATEST INSTAB IS FCSTD. THE
CAPE FROM PHL SEWD IS FCSTD TO BE QUITE ELEVATED. CONVECTIVE TEMP IS
DOABLE N AND W IF THE CLOUDS CAN BREAK SOON ENUF. THE WRF-NMM
CAPE/LI FCSTS ARE SLIDING TWD THE GFS. THUS WE HAVE KEPT THE SLGT
CHC/CHC POPS FOR THIS AFTN. WERE GOING AGAINST THE CAN RGEM WHICH
IS BONE DRY. HAVE BEEN NOTICING WITH CONVECTIVE SITU IT SEEMS TO DO
A FAIR COMP BTWN THE TWO MDLS. GOING TO PAY MORE ATTENTION TO IT
NEXT CONVECTIVE SEASON AND FROM HERE ON OUT IF NO TSRAS POP TAFTN.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
ANY LEFTOVER CONVECTION SHLD DISPT THIS EVE AS STAB PARAMETERS
SETTLE OVRNGT. OF COURSE THE QUES COMES WHETHER OR NOT ANY ONGOING
CONVECTION CAN GET HERE BEFORE IT DISPTS. FOR THIS WE WILL DEFER TO
THE CAN RGEM/UKMET THAT BOTH SAY NO. DO NOT SEE WHY WE WILL NOT GET
MORE PATCHY FOG IN THE MIX OVERNIGHT AND ADDED IT INTO THE FCST.
GUID MIN TEMPS REMAIN TIGHT AND WILL FOLLOW.

AN EXCESSIVE HEAT WATCH WILL BE ISSUED FOR URBAN AREAS ON SAT. THE
WRF-NMM AND GFS HAVE COME CLOSER WITH MOST OF THE COMPROMISING BY
THE WRF-NMM. GFS AND SREF ENSEMBLE MEANS ARE ABT 1C LWR THAN THE OP
MDLS. TODAY WE/LL GET A LOOK AT HOW MUCH THE MAX TEMPS GET SHAVED BY
THE RECENT RAIN. KEEPING UP WITH PAST PERFORMANCES (ALL SUMMER) GFS
MOS LOOKS TOO HOT. THE QUES THEN BECOMES HOW MUCH OFF THE TOP.
HISTORICALLY A 21CISH H8 TEMPS HAVE PRODUCED SOME ABT 100 IN THE
PAST, ESPECIALLY IF THE WINDS WERE W. BUT IT IS LATE AUGUST AND THE
WINDS ARE EXPECTED TO BE SW. WE SHLD GET A HEALTHY DOSE OF SUNSHINE,
ESP SERN ZONES. SO WE HAVE GONE ABT 2/3RDS OF THE WAY TWD GFS MOS.
WHAT WE LOSE IN TEMPS WE MIGHT GAIN IN MSTR. FOR THE HEAT INDEX IT
MIGHT BE A ZERO SUM GAIN. THE EXCESSIVE HEAT WRNG CRIT IS LWR IN
URBAN AREAS AND COUPLED WITH THE RECENT RUN OF COOL WEATHER THAT WE
(WELL MAYBE YOU) HAVE TO GO BACK TO 1940 TO REMEMBER MAKES FOR A
MORE DRASTIC SHOCK TO THE SYSTEM. WE WILL ISSUE THE WATCH. WRNG CRIT
SHLD NOT BE MET IN THE REST OF OUR CWA (WE BELIEVE), SO NO WATCH
THERE.

AS FAR AS CONVECTION GOES, WELL ITS NOT EVERYDAY ONE SEES 4000J
FCSTD FOR OUR CWA (BERKS COUNTY - WRFNMM), SO THAT CAUGHT OUR EYE.
THE SLOW MOVING FRONT KEEPS THE BETTER ORGANIZED WINDS OUT OF OUR
CWA DURG THE DAY, BUT WHEN CAPES GET TO ABT 2000J THAT IS USUALLY
GOOD FOR SOME (COUGH) AIR MASS TYPE TSRAS TO JUST POP. WE ALSO HAVE
AN INCREDIBLE FCSTD DROP OF 35C IN THETAE ALF SAT AFTN...WRT TO
PULSE TYPE SEVERE THAT IS ABOUT AS SUBTLE AS A MAC TRUCK. YES THE
SREF ENSEMBLE CAPES SUGGESTING ABT 2000J MIGHT BE A FAIRER
ASSESSMENT. ENUF OF A VALUE TO KEEP THE CHC IN. ALSO USUALLY ONCE
CAPES GET TO 2000J, THAT IS SFCNT JUICE TO TRIGGER TSRAS ALG SEA/BAY
BREEZE FNTS AND WE INCLUDED A CHC EVERYWHERE.

AS THE FNT COMES CLOSER, ORGANIZED CONVECTIONS SHOULD HAVE A BETTER
CHC OF CONTINUING THRU THE NGT, ACTUALLY SOME GUID POPS ARE HIEST
SAT NGT.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
NO BIG CHANGES FROM PREVIOUS THINKING. THE COLD FRONT THAT MOVES
THROUGH SUNDAY SHOULD LIMIT THE HOT WEATHER TO SATURDAY. BUT SINCE
THE FRONT IS EXPECTED TO BE A SLOW MOVER, ALL OF THE MOISTURE
ASSOCIATED WITH THE FRONT IS NOT EXPECTED TO MOVE AWAY BY SUNDAY.
THEREFORE, THERE REMAINS A CHANCE OF SHOWERS OR TSTMS INTO SUNDAY.
SUNDAY NIGHT, ENOUGH DRY AIR SHOULD ARRIVE WITH HIGH PRESSURE SO
THAT PCPN CAN BE DROPPED FROM THE WORDED ZONES FOR MONDAY INTO
WEDNESDAY. LATE WEDNESDAY INTO THURSDAY, THE HIGH MOVES OFFSHORE
ALLOWING A RETURN OF SOUTH OR SE WINDS AND WITH IT A RETURN OF
MOISTURE AND THE THREAT OF SHOWERS OR TSTMS.

&&

.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
SKIES ARE RAPIDLY CLEARING FROM THE JERSEY SHORE EAST AND NORTH OF A
MIV-ACY LINE. STILL IFR CONDITIONS FROM THE DELAWARE RIVER AND EAST
AND SOUTH OF THE LINE MENTIONED ABOVE. JUST SOME SCATTERED CLOUDS AT
THE 5-6,000 FT LEVEL ON VWP.

IN THE EXTENDED, THERE IS A CHANCE OF SHOWERS AND THUNDERSTORMS
THROUGH THE WEEKEND, ESPECIALLY IN ASSOCIATION WITH A THE COLD FRONT
MOVING THROUGH ON SUNDAY WHICH MAY LOWER CIGS AND REDUCE VSBYS AT
TIMES.

&&

.MARINE...
THE LONG PERIOD SWELLS OF 13 SECONDS NOW AT 7 SECONDS AT 44009.
WAVES ARE A LITTLE UNDER 5 FT AND 3 FT NEARSHORE. CONDITIONS SHOULD
CONTINUE TO IMPROVE TODAY. THE VISIBILITY SATELLITE SHOWS SKIES
PRETTY CLEAR FROM THE RARITAN BAY SOUTH TO LITTLE EGG INLET. CLOUDS
WILL CONTINUE TO THIN OUT OVER THE DELAWARE BAY AND SOUTHERN WATERS.

NOTE: THE NEARSHORE WATERS HAVE COOLED ABOUT 5 TO 8 DEGREES UNDER
THE CURRENT COOL SPELL. WITH THE RETURN OF VERY WARM AIR FRIDAY INTO
THE WEEKEND...HAVE TO WATCH FOR THE DEVELOPMENT OF ANY FOG BANKS
REMAINING OVER THE NEARSHORE WATERS THROUGH THE WEEKEND. LOOKS LIKE
A VERY GOOD POSSIBILITY.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...EXCESSIVE HEAT WATCH FROM SATURDAY AFTERNOON THROUGH SATURDAY
     EVENING FOR PAZ067>071.
NJ...EXCESSIVE HEAT WATCH FROM SATURDAY AFTERNOON THROUGH
     SATURDAY EVENING FOR NJZ015-017>019.
DE...EXCESSIVE HEAT WATCH FROM SATURDAY AFTERNOON THROUGH SATURDAY
     EVENING FOR DEZ001.
MD...NONE.
MARINE...NONE.

&&

SYNOPSIS...GIGI
NEAR TERM...GIGI/EBERWINE
SHORT TERM...GIGI
LONG TERM...RNS/TFG
AVIATION...ROBERSTON/EBERWINE
MARINE...ROBERTSON/EBERWINE

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
434 AM EDT FRI AUG 24 2007

DEZ002-003-MDZ008-012-015-019-020-NJZ001-007>010-012-016-PAZ054-055-
060>062-251000-
KENT DE-INLAND SUSSEX-CECIL-KENT MD-QUEEN ANNES-TALBOT-CAROLINE-
SUSSEX-WARREN-MORRIS-HUNTERDON-SOMERSET-MIDDLESEX-SALEM-CARBON-
MONROE-BERKS-LEHIGH-NORTHAMPTON-
434 AM EDT FRI AUG 24 2007

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

.DAY ONE...TODAY AND TONIGHT

SOME PATCHY AND LOCALLY DENSE FOG WILL OCCUR THROUGH THE MORNING
COMMUTE TODAY.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

AN UNSEASONABLY HOT AND HUMID DAY IS EXPECTED ON SATURDAY. HIGH
TEMPERATURES OTHER THAN IN THE POCONOS SHOULD REACH INTO THE 90S
WITH HEAT INDICES POSSIBLY TOPPING 100 DEGREES. STRONG TO POSSIBLY
SEVERE THUNDERSTORMS ARE POSSIBLE SATURDAY AFTERNOON INTO NIGHT. THIS
THREAT FOR STRONG THUNDERSTORMS MIGHT LINGER INTO SUNDAY ACROSS SOUTHEAST
NEW JERSEY AND DELMARVA.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

NJZ013-020>023-027-251000-
WESTERN MONMOUTH-OCEAN-CUMBERLAND-ATLANTIC-CAPE MAY-
SOUTHEASTERN BURLINGTON-
434 AM EDT FRI AUG 24 2007

...DENSE FOG ADVISORY IN EFFECT UNTIL 9 AM EDT THIS MORNING...

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

.DAY ONE...TODAY AND TONIGHT

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

   DENSE FOG ADVISORY.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

AN UNSEASONABLY HOT AND HUMID DAY IS EXPECTED ON SATURDAY. HIGH
TEMPERATURES SHOULD REACH INTO THE 90S WITH HEAT INDICES REACHING
100 TO 105 DEGREES. STRONG TO POSSIBLY SEVERE THUNDERSTORMS ARE POSSIBLE
SATURDAY AFTERNOON INTO NIGHT. THIS THREAT FOR STRONG THUNDERSTORMS MIGHT
LINGER INTO SUNDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

DEZ001-NJZ015-017>019-PAZ067>071-251000-
NEW CASTLE-MERCER-GLOUCESTER-CAMDEN-NORTHWESTERN BURLINGTON-CHESTER-
MONTGOMERY-BUCKS-DELAWARE-PHILADELPHIA-
434 AM EDT FRI AUG 24 2007

...EXCESSIVE HEAT WATCH IN EFFECT FROM SATURDAY AFTERNOON THROUGH
SATURDAY EVENING...

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

.DAY ONE...TODAY AND TONIGHT

SOME PATCHY AND LOCALLY DENSE FOG WILL PERSIST THROUGH THE MORNING
COMMUTE, ESPECIALLY IN NEW JERSEY.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

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

   EXCESSIVE HEAT WATCH.

STRONG TO POSSIBLY SEVERE THUNDERSTORMS ARE POSSIBLE SATURDAY AFTERNOON
INTO NIGHT. THIS THREAT FOR STRONG THUNDERSTORMS MIGHT LINGER INTO SUNDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

NJZ014-024>026-251000-
EASTERN MONMOUTH-ATLANTIC COASTAL CAPE MAY-COASTAL ATLANTIC-
COASTAL OCEAN-
434 AM EDT FRI AUG 24 2007

...DENSE FOG ADVISORY IN EFFECT UNTIL 9 AM EDT THIS MORNING...

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

.DAY ONE...TODAY AND TONIGHT

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

 DENSE FOG ADVISORY.

THERE IS A LOW TO MODERATE RISK OF RIP CURRENTS TODAY AND TONIGHT.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

STRONG TO POSSIBLY SEVERE THUNDERSTORMS ARE POSSIBLE SATURDAY AFTERNOON
INTO NIGHT. THIS THREAT FOR STRONG THUNDERSTORMS MIGHT LINGER INTO
SUNDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

DEZ004-251000-
DELAWARE BEACHES-
434 AM EDT FRI AUG 24 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHERN DELAWARE.

.DAY ONE...TODAY AND TONIGHT

THERE IS A LOW TO MODERATE RISK OF RIP CURRENTS TODAY AND TONIGHT.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

STRONG TO POSSIBLY SEVERE THUNDERSTORMS ARE POSSIBLE SATURDAY AFTERNOON
INTO NIGHT. THIS THREAT FOR STRONG THUNDERSTORMS MIGHT LINGER INTO
SUNDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

ANZ430-431-450>455-251000-
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-
434 AM EDT FRI AUG 24 2007

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

.DAY ONE...TODAY AND TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

MARINERS BE WARY FOR THUNDERSTORMS THAT MIGHT REQUIRE SPECIAL MARINE
WARNINGS ON SATURDAY AND SUNDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

TFG