Scattered pulse type strong to severe thunderstorms affected mainly the far eastern portions of Pennsylvania during the afternoon of the 4th.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS PHI wrote it up.
Scattered pulse type strong to severe thunderstorms affected mainly the far eastern portions of Pennsylvania during the afternoon of the 4th.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Philadelphia/Mount Holly wrote its last area forecast discussion before the first event at Aug 4, 11:17 AM EST, 1 hour 28 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 1217 PM EDT SAT AUG 4 2012 .SYNOPSIS... HIGH PRESSURE CENTERED EAST OF THE MID ATLANTIC COAST WILL REMAIN NEARLY STATIONARY THROUGH EARLY SUNDAY...BEFORE MOVING EAST. A COLD FRONT WILL APPROACH THE REGION LATE SUNDAY...THEN CROSS THE AREA SUNDAY NIGHT INTO MONDAY MORNING. THE FRONT MAY STALL NEARBY AS WEAK HIGH PRESSURE BUILDS EAST FROM THE OHIO VALLEY. A COLD FRONT WILL CROSS THE AREA LATE WEDNESDAY. YET ANOTHER COLD FRONT WILL APPROACH THE REGION LATE NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... A SURFACE ANALYSIS REVEALS TWO BOUNDARIES. A WEAK COOL FRONT IS DRAPED FROM NEAR SOUTHERN NEW ENGLAND WESTWARD TO LAKE ERIE THEN BACK INTO THE MIDWEST. ANOTHER BOUNDARY, IN THE FORM OF A WEAK WARM FRONT, WAS DRAPED ACROSS THE UPPER OHIO VALLEY. HIGH PRESSURE ANCHORED ACROSS THE WESTERN ATLANTIC IS MAINTAINING A SOUTHERLY FLOW OF VERY WARM AND HUMID AIR ACROSS OUR REGION. THE AREAS OF STRATUS/FOG HAS LIFTED INTO MORE OF A STRATOCUMULUS AND CUMULUS FIELD AS SURFACE HEATING CONTINUES. THERE REALLY IS NOT MUCH OF A TRIGGER TODAY FOR CONVECTION, AT LEAST ON THE LARGER SCALE, THEREFORE WE LOOK MORE TOWARD THE MESOSCALE. THE 12Z RAOBS FROM STERLING, VA AND UPTON, NY INDICATE PLENTY OF INSTABILITY ALREADY IN PLACE ALONG WITH A RATHER MOIST PROFILE ESPECIALLY IN THE LOWER LEVELS. THERE IS DRIER AIR IN THE MID LEVELS, AND THE OVERALL PROFILES LOOK SIMILAR TO YESTERDAY. SINCE THE STEERING FLOW IS LIGHT ONCE AGAIN, SEA OR BAY BREEZES, TERRAIN AND THE OVERALL SOUTH/SOUTHEAST LOW-LEVEL FLOW SHOULD BE THE MAIN TRIGGERS FOR ANY CONVECTIVE DEVELOPMENT. THE CONVECTIVE TEMPERATURES HAVE BEEN REACHED ACROSS MUCH OF THE AREA AND ISOLATED CONVECTION HAS ALREADY INITIATED. THIS IS EXPECTED TO CONTINUE WITH CELLS TENDING TO PULSE UP WITH NEW DEVELOPMENT OCCURRING ON OUTFLOWS. THE OVERALL COVERAGE LOOKS LIMITED, THEREFORE WILL CONTINUE WITH SLIGHT CHC POPS FOR ISOLATED ACTIVITY FOR NOW. GIVEN THE MAGNITUDE OF THE INSTABILITY AND THE POTENTIAL ONCE AGAIN OF LOCALLY FOCUSED LOW-LEVEL CONVERGENCE, UPDRAFTS SHOULD BE EFFICIENT HOWEVER THE LIGHT FLOW MAY RESULT IN LOCALIZED AND BRIEF DOWNBURSTS. LOCALLY HEAVY RAIN WILL ALSO OCCUR GIVEN THE PW VALUES AROUND 1.8 INCHES. JUST LIKE YESTERDAY, STORMS WILL BE CAPABLE OF RAPID DEVELOPMENT. THE WARMING HAS ACCELERATED SOME NOW AS THE LOWER CLOUDS THINNED OUT. AS OF NOW, NO MAJOR CHANGES WERE MADE TO THE HIGHS BUT THE HOURLY GRIDS NEEDED SOME ADJUSTMENTS. THE DEW POINTS CONTINUE TO BE IN THE 70S ACROSS MUCH OF THE AREA AS OF 16Z, HOWEVER THESE SHOULD LOWER A BIT THIS AFTERNOON WITH CONTINUED HEATING. HEAT INDICES THOUGH WILL APPROACH 100 DEGREES FOR SOME LOCALES FOR A TIME THIS AFTERNOON. SINCE WE HAVE EXPERIENCED SEVERAL HEAT WAVES THIS SUMMER, WE ARE NOW IN AUGUST AND MET CRITERIA SHOULD NOT BE WIDESPREAD, NO HEAT RELATED HEADLINES ARE ANTICIPATED FOR TODAY BUT IT WILL BE ANOTHER HOT AND HUMID DAY. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/... DRY WX OVERNIGHT AS ANY EVE CONVECTION DISSIPATES. THEN ANOTHER WARM AND HUMID NIGHT IS IN STORE. A VERY ROBUST LOW PRESSURE SYSTEM WILL BEGIN ADVANCING EWD ACRS CANADA AND BY DAYBREAK, A CDFNT WILL BE ACRS THE OH VLY. MOST OF THE GUID KEEPS ANY SHOWERS OR TSRA WELL TO THE W THRU THE PD, BUT THERE SOME GUID DOES INDICATE THAT THERE COULD BE LOW POPS TO THE W BY DAYBREAK. FOR NOW, WILL MAINTAIN SCHC. && .LONG TERM /SUNDAY THROUGH FRIDAY/... SUNDAY AND SUNDAY NIGHT LOOK TO BE THE MOST ACTIVE TIME DURING THE LONG TERM...WITH AN INCREASING ZONAL MID LEVEL FLOW BRINGING FRONTS EVERY COUPLE OF DAYS THROUGH THE END OF NEXT WEEK. THIS WOULD SUPPORT TEMPERATURES NEAR NORMAL FOR MUCH OF THE UPCOMING WEEK. THERE IS SOME INDICATION THAT A WEAK WARM FRONT MAY TRY TO MOVE NORTH THROUGH THE LEHIGH VALLEY...SOUTHERN POCONOS AND NORTHWEST NEW JERSEY EARLY SUNDAY MORNING. THIS WOULD HAVE THE EFFECT OF KEEPING LOW CLOUDS IN A BIT LONGER SUNDAY MORNING IN THESE AREAS THAN FURTHER SOUTH. THERE COULD ALSO BE SOME ELEVATED CONVECTION WITH THE WARM FRONT. AFTER THIS...THE ENTIRE AREA WILL BE IN THE WARM SECTOR AHEAD OF THE SLOW MOVING COLD FRONT. THE MID LEVEL SHORT WAVING APPROACHING FROM THE GREAT LAKES APPEARS TO SLOW SUNDAY AFTERNOON INTO SUNDAY EVENING. THE SLOWER TIMING WOULD SLOW THE TIMING OF THE SURFACE FRONT AS THE BULK OF THE MID LEVEL SUPPORT STARTS TO SHEAR OUT TO THE NORTHEAST. BASED ON THE ABOVE...THE CONVECTIVE COVERAGE WAS SLOWED SUNDAY AFTERNOON COMPARED TO THE PREVIOUS FORECAST. THE BEST COVERAGE WILL OCCUR ACROSS NORTHWEST AREAS IN THE MID TO LATE AFTERNOON...WHILE MUCH OF SOUTHEAST NEW JERSEY AND CENTRAL AND SOUTHERN DELAWARE COULD BE DRY MUCH OF THE DAY. INSTABILITY SHOULD BE AT LEAST MARGINAL... WITH CLOUD COVER HAVING SOME IMPACT IN THE MORNING. WHILE THE POTENTIAL FOR DEEP CONVECTION CERTAINLY EXISTS...THERE IS SOME QUESTION WHICH FORM IT WILL TAKE. MODIFIED MODEL SOUNDINGS SHOW DECENT INSTABILITY (WITH MEAN LAYER CAPE VALUES HIGHEST NORTHWEST OF PHILADELPHIA). DRY MID LEVELS SUGGEST GUSTY WINDS WITH CELLS THAT DEVELOP IN THE AFTERNOON AHEAD OF THE COLD FRONT. WHILE MID LEVEL LAPSE RATES ARE FAIRLY WEAK...THE DECENT MEAN LAYER CAPE VALUES SUGGEST STRONG ENOUGH UPDRAFTS FOR SMALL HAIL. BULK SHEAR DOES NOT INCREASE ACROSS NORTHERN AREAS UNTIL LATE AFTERNOON. BY THAT TIME...THE COMBINATION OF SHEAR AND INSTABILITY COULD LEAD TO ORGANIZE CONVECTION...MOST LIKELY TAKING THE FORM OF SMALL LINE AND BOW SEGMENTS. IN THESE STRUCTURES...GUSTY WINDS WOULD BE MOST LIKELY. 850 MB TEMPERATURES CAN SUPPORT HIGHS IN THE LOWER 90S OUTSIDE OF THE WATER AND THE TERRAIN. CLOUDINESS IN THE MORNING COULD INHIBIT THIS A BIT...AND HIGHS WERE GENERALLY A BLEND OF MOS NUMBERS AND THE PREVIOUS FORECAST. IN ADDITION...HEATING WILL ALLOW WINDS TO MIX DURING THE AFTERNOON AS A LOW LEVEL JET PASSES. WIND GUSTS TO 30 MPH ARE POSSIBLE IN THE AFTERNOON...ESPECIALLY DURING MAXIMUM HEATING. THE BEST CONVECTIVE POTENTIAL COULD END UP BEING SUNDAY EVENING...AS THE COMBINATION OF SHEAR AND REMAINING INSTABILITY SUPPORTS STRUCTURES THAT SUPPORT GUSTY WINDS. IN ADDITION...PRECIPITABLE WATER VALUES OVER 2 INCHES RAISES THE SPECTER OF FLASH FLOODING. THE POTENTIAL IS DETAILED IN THE HYDROLOGY SECTION BELOW. ALL AREAS SHOULD SEE SHOWERS AND THUNDERSTORMS SUNDAY NIGHT AHEAD OF THE SLOW MOVING COLD FRONT. THE AIRMASS CHANGE BEHIND THE FRONT SHOULD AFFECT NORTHWEST AREAS AFTER MIDNIGHT SUNDAY NIGHT...AND STABILITY SHOULD INCREASE AS THE NIGHT GOES ON. FURTHER SOUTHEAST...THE AIRMASS CHANGE PROBABLY WAITS FOR MONDAY MORNING...SO MARGINAL INSTABILITY SUPPORTS THUNDER FOR MUCH OF THE NIGHT. LOWS PROBABLY END UP CLOSER TO THE MOS BLEND AS THE AIRMASS CHANGE IS SLOW AT BEST FOR MUCH OF THE AREA. THERE IS A CONSIDERABLE AMOUNT OF SPREAD IN THE MODEL SUITE CONCERNING THE COLD FRONTAL PASSAGE MONDAY. THE 0000 UTC NAM IS BY ITSELF KEEPING THE FRONT FROM EXITING CENTRAL ZONES (POSSIBLY UNTIL SOMETIME TUESDAY). THIS IS DESPITE THE FACT THAT MOST SHORT TERM MODELS HAVE SIMILAR TIMING ABOVE THE SURFACE. FOR THIS FORECAST... THE 0000 UTC NAM WAS LARGELY IGNORED BECAUSE OF WHAT APPEARS TO BE SLUGGISHNESS WITH THE FRONT. WITH THIS IN MIND...THE POTENTIAL FOR SHOWERS AND THUNDERSTORMS WAS RETAINED FOR ROUGHLY THE SOUTHERN ONE-HALF TO ONE-THIRD OF THE AREA. FURTHER NORTH...THE AIRMASS SHOULD BE SUFFICIENTLY STABLE TO PRECLUDE CONVECTION. FURTHER SOUTH...THERE IS SOME INDICATION THAT THERE COULD BE ENOUGH INSTABILITY...COMBINED WITH MARGINAL (AND DECREASING) BULK SHEAR FOR POSSIBLE ORGANIZATION MONDAY AFTERNOON. THE AIRMASS WILL BE IN TRANSITION MONDAY...AS THE LOWER PORTION OF THE COLUMN COOLS SLOWLY. BASED ON THIS...HIGHS WERE MAINLY BASED ON THE MOS BLEND. A SLIGHT CHANCE OF SHOWERS WAS RETAINED FOR SOUTHERNMOST AREAS MONDAY NIGHT AS RESIDUAL INSTABILITY WANES. OTHERWISE...MONDAY NIGHT LOOKS DRY. AT THIS POINT...PATCHY FOG AND RADIATIONAL COOLING LOOK UNLIKELY IN THE TRANSITIONING AIRMASS. THE STALLING OR STALLED FRONT COULD ACT AS A FOCUS FOR CONVECTION TUESDAY AFTERNOON...ESPECIALLY SOUTH OF A KILG-KACY LINE. MODIFIED MODEL SOUNDINGS SHOW DECENT MEAN LAYER CAPES...WHICH COULD SUPPORT STRONG UPDRAFTS. SHEAR MAY BE LACKING...BUT A CHANCE OF SHOWERS AND THUNDERSTORMS WAS RETAINED. MID LEVEL TROUGHING APPROACHING FROM THE WESTERN GREAT LAKES COULD PROVIDE ENOUGH COOLING IN THE MID LEVELS TO ALLOW WIDELY SCATTERED CONVECTION TO DEVELOP. THE LIMITING FACTOR HERE COULD BE A FOCUS. THERE IS ENOUGH MODEL SPREAD FOR THE END OF THE WEEK CONCERNING THE EVOLUTION OF THE MID LEVEL PATTERN TO KEEP THE CURRENT FORECAST FOR THAT TIME LARGELY INTACT. && .AVIATION /16Z SATURDAY THROUGH WEDNESDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. AS OF 16Z, THE AREAS OF STRATUS AND FOG HAVE MOSTLY LIFTED INTO A STRATOCUMULUS AND CUMULUS DECK DUE TO CONTINUED HEATING. AS A RESULT, SOME MVFR CEILINGS LINGERING FOR A TIME ARE EXPECTED TO INCREASE TO VFR. THE CEILINGS WILL SCATTERED OUT AT TIMES ESPECIALLY CLOSER TO DELAWARE BAY AND THE COAST, AND ALSO NEAR RAIN COOLED OUTFLOWS. WE THEN TURN TO THE SHOWER OR THUNDERSTORM POTENTIAL THIS AFTERNOON. IT APPEARS LIKE YESTERDAY THAT SEA OR BAY BREEZES WILL COME INTO PLAY ALONG WITH RAIN COOLED OUTFLOW FROM STORMS. THESE FEATURES SHOULD BE THE MAIN FOCUS FOR SHOWERS OR THUNDERSTORMS. SOME ACTIVITY HAS ALREADY DEVELOPMENT AND THIS TREND IS EXPECTED TO CONTINUE INTO THIS EVENING. IT STILL APPEARS THAT THE COVERAGE WILL BE MOSTLY ISOLATED, THEREFORE WE WILL MONITOR RADAR IMAGERY AND TRENDS AND MAKE AMENDMENTS AS NEEDED. LOCALLY GUSTY WINDS AND HEAVY RAIN WILL ACCOMPANY ANY STRONGER STORMS, AND THIS ACTIVITY SHOULD DISSIPATE FAIRLY QUICKLY DURING THE EVENING AS THEY ARE MAINLY DRIVEN BY DAYTIME HEATING. THE WINDS WILL GENERALLY BE FROM THE SOUTHEAST OR SOUTH TO NEAR 10 KNOTS DURING THE AFTERNOON. THE LOW-LEVEL MOISTURE WILL REMAIN HIGH AGAIN TONIGHT, AND WITH LIGHT WINDS AND ANY POCKETS OF RAINFALL DURING THE DAY, MAY RESULT IN LOCAL FOG AND STRATUS REDEVELOPING OVERNIGHT. OUTLOOK... SUNDAY...MVFR/IFR CONDITIONS ARE POSSIBLE EARLY SUNDAY MORNING NORTHWEST OF KPHL. AFTER THIS...VFR CONDITIONS ARE EXPECTED...WITH SCATTERED SHOWERS AND THUNDERSTORMS. SOME OF THE STORMS COULD PRODUCE GUSTY WINDS. SUNDAY NIGHT...SHOWERS AND THUNDERSTORMS ARE EXPECTED...WITH PATCHY MVFR CONDITIONS WITH THE STORMS. OUTSIDE OF THE SHOWERS AND STORMS...VFR CONDITIONS ARE EXPECTED. MONDAY...VFR CONDITIONS ARE EXPECTED. DEPENDING ON THE POSITION OF A COLD FRONT...SCATTERED THUNDERSTORMS ARE POSSIBLE...MAINLY SE OF KPHL. TUESDAY...VFR CONDITIONS ARE EXPECTED. SCATTERED THUNDERSTORMS ARE POSSIBLE SOUTH OF KPHL. WEDNESDAY...MAINLY VFR CONDITIONS ARE EXPECTED WITH SCATTERED SHOWERS AND THUNDERSTORMS POSSIBLE...MAINLY IN THE AFTERNOON. && .MARINE... HIGH PRESSURE REMAINS OFF THE ATLC COAST AND THINGS ARE RELATIVELY QUIET ON THE AREA WATERS. EXPECT A SE TO S WIND WITH SPEEDS IN THE 10-15 KT RANGE. SCA CONDS ARE NOT EXPECTED THRU THE PD. OUTLOOK... THE TIGHTENING GRADIENT BETWEEN THE EXITING SURFACE HIGH TO THE EAST AND THE APPROACHING COLD FRONT COULD RESULT IN SMALL CRAFT WINDS DEVELOPING AS EARLY AS SUNDAY AFTERNOON. MODEL SOUNDINGS SUGGEST THE BEST TIMING FOR SMALL CRAFT WINDS SHOULD BE LATER SUNDAY AFTERNOON INTO EARLY MONDAY MORNING (2000 UTC SUNDAY THROUGH 0900 UTC MONDAY). MODEL SOUNDINGS SUGGEST THAT 30 TO 35 KNOTS OF WIND WILL BE AVAILABLE AT THE TOP OF THE INVERSION AS A LOW LEVEL JET PASSES SUNDAY EVENING. THIS WOULD SUGGEST A LOW PROBABILITY OF GALE FORCE SOUTH TO SOUTHWEST WIND GUSTS. THE SOUTH TO SOUTHWEST WIND DIRECTION DOES NOT TYPICALLY SUPPORT GALE FORCE GUSTS...ESPECIALLY IN THE SUMMER...SO WIND GUSTS WERE CAPPED AT 30 KNOTS FOR NOW. THE INCREASING SOUTH TO SOUTHWEST FETCH SHOULD ALLOW SEAS TO BUILD TO 5 FEET ON THE OCEAN...ESPECIALLY ACROSS NORTHERN SECTIONS SUNDAY EVENING INTO SUNDAY NIGHT. AT THIS POINT...THIS IS IN LINE WITH THE LATEST WAVEWATCH OUTPUT...WHICH SEEMS REASONABLE GIVEN THE WIND DIRECTION. SINCE THIS IS MAINLY A MID THIRD INTO FOURTH PERIOD EVENT...WE HELD OFF ON THE SMALL CRAFT ADVISORY EARLY THIS MORNING. THERE IS SOME MODEL SPREAD WITH THE TIMING OF THE COLD FRONTAL PASSAGE...BUT MOST MODEL SUPPORT WINDS DROPPING BELOW SMALL CRAFT LEVELS FOR MONDAY. TIMING OF SEAS ON THE OCEAN COULD BE MORE PROBLEMATIC...AS THE SOUTHERLY SWELL TAKES TIME TO SORT ITSELF OUT. IT IS POSSIBLE SEAS COULD REMAIN ABOVE 5 FEET INTO MONDAY MORNING. AFTER THIS...WINDS AND SEAS LOOK TO REMAIN BELOW SMALL CRAFT LEVELS MONDAY NIGHT INTO EARLY WEDNESDAY. THERE IS SOME INDICATION (BASED MAINLY ON MODEL SOUNDINGS) THAT WINDS IN THE SOUTHWEST FLOW COULD GUST TO NEAR SMALL CRAFT LEVELS ON THE OCEAN WEDNESDAY EVENING. && .HYDROLOGY... PRECIPITABLE WATER VALUES REACH 2.25 INCHES SUNDAY AFTERNOON AND EVENING (ESPECIALLY OVER NEW JERSEY...WHICH IS GREATER THAN TWO STANDARD DEVIATIONS ABOVE NORMAL). THIS ALONE RAISES THE THREAT FOR FLASH FLOODING. BASED ON THE MID LEVEL FLOW...THE STORM MOTION SHOULD BE SUFFICIENT TO MITIGATE AT LEAST SOME OF THE FLASH FLOOD THREAT FROM SLOW MOVING STORMS. HOWEVER...TRAINING CELLS COULD BE AN ISSUES...ESPECIALLY IF CELLS WITH VERY HEAVY RAIN DEVELOP AHEAD OF MORE ORGANIZED CONVECTIVE STRUCTURES. ONE VULNERABLE AREA WOULD BE ACROSS A PORTION OF THE DELAWARE VALLEY AND LEHIGH VALLEY...WHERE ONE HOUR FLASH FLOOD VALUES ARE AS LOW AS 1.60 INCHES. THE OTHER...LARGER VULNERABLE AREA WOULD BE NORTH CENTRAL AND NORTHWEST NEW JERSEY. IN THIS AREA...ONE HOUR FLASH FLOOD GUIDANCE NUMBERS ARE GENERALLY BETWEEN 1.50 AND 2.00 INCHES. MORE ORGANIZED CONVECTION WOULD PROBABLY AFFECT THIS AREA FIRST SUNDAY AFTERNOON... SO IT IT PROBABLY THE MOST VULNERABLE FOR FLASH FLOODING. IT IS TOO EARLY FOR FLASH FLOOD HEADLINES...BUT THE THREAT WILL BE OUTLINED IN THE HAZARDOUS WEATHER OUTLOOK. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...NONE. && SYNOPSIS...HAYES NEAR TERM...GORSE SHORT TERM...NIERENBERG LONG TERM...HAYES AVIATION...GORSE/HAYES MARINE...HAYES/NIERENBERG HYDROLOGY...HAYES
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 1045 AM EDT SAT AUG 4 2012 DEZ002-003-MDZ008-012-015-019-020-NJZ001-007>010-012-013-016-020>023- 027-PAZ054-055-060>062-051445- KENT-INLAND SUSSEX-CECIL-KENT MD-QUEEN ANNES-TALBOT-CAROLINE-SUSSEX- WARREN-MORRIS-HUNTERDON-SOMERSET-MIDDLESEX-WESTERN MONMOUTH-SALEM- OCEAN-CUMBERLAND-ATLANTIC-CAPE MAY-SOUTHEASTERN BURLINGTON-CARBON- MONROE-BERKS-LEHIGH-NORTHAMPTON- 1045 AM EDT SAT AUG 4 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL DELAWARE...SOUTHERN DELAWARE...NORTHEAST MARYLAND...CENTRAL NEW JERSEY...NORTHERN NEW JERSEY...NORTHWEST NEW JERSEY...SOUTHERN NEW JERSEY...EAST CENTRAL PENNSYLVANIA AND NORTHEAST PENNSYLVANIA. .DAY ONE...TODAY AND TONIGHT. THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER LOW AT THIS TIME. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY. THUNDERSTORMS MAY PRODUCE STRONG WINDS AND LOCALLY HEAVY RAINFALL SUNDAY AND SUNDAY NIGHT. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. DEZ001-NJZ015-017>019-PAZ067>071-051445- NEW CASTLE-MERCER-GLOUCESTER-CAMDEN-NORTHWESTERN BURLINGTON-CHESTER- MONTGOMERY-BUCKS-DELAWARE-PHILADELPHIA- 1045 AM EDT SAT AUG 4 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHERN DELAWARE...CENTRAL NEW JERSEY...SOUTHERN NEW JERSEY AND SOUTHEAST PENNSYLVANIA. .DAY ONE...TODAY AND TONIGHT. HEAT INDEX VALUES THIS AFTERNOON WILL APPROACH 100 DEGREES ACROSS SOME AREAS. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY. THUNDERSTORMS MAY PRODUCE STRONG WINDS AND LOCALLY HEAVY RAINFALL SUNDAY AND SUNDAY NIGHT. IN ADDITION...HEAT INDEX VALUES WILL TOP OUT BETWEEN 95 AND 100 DEGREES SUNDAY AFTERNOON. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. DEZ004-NJZ014-024>026-051445- DELAWARE BEACHES-EASTERN MONMOUTH-ATLANTIC COASTAL CAPE MAY- COASTAL ATLANTIC-COASTAL OCEAN- 1045 AM EDT SAT AUG 4 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHERN DELAWARE...CENTRAL NEW JERSEY AND SOUTHERN NEW JERSEY. .DAY ONE...TODAY AND TONIGHT. THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER LOW AT THIS TIME. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY. THUNDERSTORMS MAY PRODUCE STRONG WINDS AND LOCALLY HEAVY RAINFALL SUNDAY AND SUNDAY NIGHT. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. ANZ430-431-450>455-051445- 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- 1045 AM EDT SAT AUG 4 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR ATLANTIC COASTAL WATERS AND DELAWARE BAY WATERS. .DAY ONE...TODAY AND TONIGHT. THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER LOW AT THIS TIME. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY. THUNDERSTORMS MAY PRODUCE STRONG WINDS AND LOCALLY HEAVY RAINFALL SUNDAY AND SUNDAY NIGHT. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 112 PM EDT SAT AUG 4 2012 NJZ017>019-PAZ068>071-041815- BUCKS PA-CAMDEN NJ-DELAWARE PA-GLOUCESTER NJ-MONTGOMERY PA- NORTHWESTERN BURLINGTON NJ-PHILADELPHIA PA- 112 PM EDT SAT AUG 4 2012 ...A STRONG THUNDERSTORM WILL AFFECT BUCKS...BURLINGTON...CAMDEN... DELAWARE...GLOUCESTER...MONTGOMERY AND PHILADELPHIA COUNTIES... AT 110 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A STRONG THUNDERSTORM 3 MILES EAST OF CAMDEN...MOVING NORTH AT 15 MPH. THE THUNDERSTORM WILL BE NEAR PALMYRA AND TACONY AROUND 130 PM...NORTHEAST PHILADELPHIA AND ROCKLEDGE AROUND 145 PM. AND FEASTERVILLE AND BRYN ATHYN AROUND 200 PM. VERY HEAVY RAIN WILL FALL FROM THIS STORM...AND WILL CAUSE WATER TO POND ON ROADS AND QUICKLY FILL POOR DRAINAGE AREAS. WIND GUSTS TO 40 MPH ARE POSSIBLE WITH THIS STORM. EXPECT SMALL HAIL AND FREQUENT...DANGEROUS CLOUD TO GROUND LIGHTNING FROM THIS STORM. LAT...LON 4019 7537 4016 7473 3980 7481 3982 7533 IOVINO
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
118 PM EDT SAT AUG 4 2012
DEZ001-MDZ008-PAZ067-041815-
CECIL MD-CHESTER PA-NEW CASTLE DE-
118 PM EDT SAT AUG 4 2012
...A STRONG THUNDERSTORM WILL AFFECT CECIL...CHESTER AND NEW CASTLE
COUNTIES...
AT 115 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 3 MILES WEST OF NEWARK...MOVING NORTH AT 15 MPH.
THE THUNDERSTORM WILL BE NEAR KEMBLESVILLE AND GLEN WESTOVER AROUND
130 PM...LADENBERG AND NORTH STAR AROUND 145 PM...WEST GROVE AND
AVONDALE AROUND 200 PM...AND COCHRANVILLE AND HOMEVILLE AROUND 215
PM.
VERY HEAVY RAIN WILL FALL FROM THIS STORM...AND WILL CAUSE WATER TO
POND ON ROADS AND QUICKLY FILL POOR DRAINAGE AREAS.
WIND GUSTS TO 40 MPH ARE POSSIBLE WITH THIS STORM.
EXPECT SMALL HAIL AND FREQUENT...DANGEROUS CLOUD TO GROUND LIGHTNING
FROM THIS STORM.
LAT...LON 3988 7600 3990 7600 3992 7559 3952 7562
3951 7598 3986 7602
IOVINOThe Philadelphia radar (KDIX), 62 km away, was scanning. The volume nearest the first event began at 17:45 UTC.
3 thunderstorm wind. Local standard time, as filed.
A severe thunderstorm knocked down a few trees and wires in Abington Township.
A severe thunderstorm knocked down a few trees and wires in Horsham Township. In addition, large tree limbs were knocked down along Maple Avenue and a fence was blown over along Pennsylvania State Route 611.
A severe thunderstorm knocked down a few trees and wires in Easton.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2012Every state in 2012This day in weather historyWarnings in Pennsylvania, August 2012
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 408687, 408693, 408695.