An unusually intense upper level low for August helped trigger thunderstorms in Pennsylvania on the 11th. While the hail did not reach severe criteria, small hail was reported with the thunderstorms in both Berks and Monroe Counties.
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The episode as NWS PHI wrote it up.
An unusually intense upper level low for August helped trigger thunderstorms in Pennsylvania on the 11th. While the hail did not reach severe criteria, small hail was reported with the thunderstorms in both Berks and Monroe Counties.
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 11, 3:10 AM EST, 4 hours 40 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 410 AM EDT MON AUG 11 2008 .SYNOPSIS... AN UPPER LEVEL LOW OVER WESTERN PENNSYLVANIA EARLY THIS MORNING WILL DRIFT EAST PASSING OVER EASTERN PENNSYLVANIA AND NEW JERSEY TODAY. THE LOW WILL THEN LIFT TO THE NORTHEAST ON TUESDAY PASSING OVER THE COASTAL WATERS OF NEW ENGLAND. AS THE LOW DEPARTS, HIGH PRESSURE IS FORECAST TO BUILD IN FROM THE WEST AND NORTHWEST FOR THE MID TO LATE WEEK PERIOD. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... THE DAY AND EVENING CREW ARE SLEEPING WELL AFTER ISSUING 50 SEVERE/TORNADO/FLOOD/MARINE WARNINGS ON SUNDAY. A TOTAL OF 32 SVRS WERE ISSUED FOR 85 COUNTIES. A QUICK LSR COUNT CAME UP WITH 92 ENTRIES, MAINLY HAIL. THANKS TO ALL OF OUR SPOTTERS AND PARTNERS COLD CORE LOWS ALWAYS INCREASE THE WORKLOAD AND THIS CURRENT ONE, WHICH IS PUSHING FOUR STANDARD DEVIATIONS, IS NO DIFFERENT. THE UPPER LOW, NOW OVER WESTERN PENNSYLVANIA WILL BEGIN TO OPEN UP TODAY AND BE POSITIONED OVER NYC EARLY THIS EVENING. WHILE SHOWERS AND THUNDERSTORMS ARE MENTIONED FOR TODAY IN SOME CAPACITY, WE ARE NOT EXPECTING A REPEAT OF YESTERDAY. STABILITY PARAMETERS ARE CUT IN HALF IN SOME CASES. PLUS THE STRONGEST MID LEVEL FLOW IS FORECAST TO PUSH OFF THE COAST(ALONG WITH THE SURFACE FRONT) BEFORE THE BEST DIURNAL INSTABILITY SETS UP. THAT SAID, I STILL THINK WELL SEE REPORTS OF SMALL HAIL TODAY WITH FREEZING LEVELS BOTTOMING OUT NEAR 8500 FEET. IS THIS AUGUST? BEFORE THE REGION GETS BACK INTO SOME SHOWERS AND THUNDERSTORMS (BEST CHANCES THE FARTHER NORTH YOU GO), WELL HAVE TO CONTEND WITH SOME MORNING FOG AS THE TEMPERATURES HAVE DROPPED BACK INTO THE MIDDLE 50S IN SOME LOCALES. THE 11U-3.9U SATELLITE IMAGERY CONTINUES TO SHOW AN AMPLE AMOUNT OF CLOUDS BETWEEN SCRANTON AND PITTSBURGH, NORTH OF THE MASON-DIXON LINE. ALTHOUGH WE SHOULD SEE SOME BLUE TODAY (NORTHERN AND CENTRAL ZONES), THE AFOREMENTIONED CLOUDS WILL MAKE FOR A MOSTLY CLOUDY DAY. THE SOUTHERN ZONES WILL SEE LESS CLOUDS. H8 TEMPS ARE FORECAST TO BE IN THE +10 TO +12 DEGREES C RANGE TODAY. 00Z STAT GUIDANCE WAS IN LINE (AT LEAST FOR THE 1ST PERIOD) AND WAS ACCEPTED. TEMPERATURES SHOULD RANGE FROM THE MID 60S TO LOWER 70S ACROSS THE HIGHER TERRAIN OF OUR NORTHWESTERN ZONES TO AROUND 80 DEGREES ACROSS THE SOUTHERN ONES. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/... AS THE UPPER LOW MAKES ITS WAY FROM THE NYC AREA THIS EVENING TO THE NEW ENGLAND COASTAL WATERS, WEAK SURFACE HIGH PRESSURE WILL BUILD ACROSS THE REGION THROUGH TUESDAY. THIS WILL HELP TO MODERATE THE TEMPERATURES. PER THE 00Z MODELS RUNS, THE REGION COULD SEE SOME ISOLATED CONVECTION WEDNESDAY AS WE GET SQUEEZED BY TWO WEAK LOW PRESSURE SYSTEMS. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... WEAK LOW PRESSURE MAY PASS WELL TO OUR SOUTHEAST ON WEDNESDAY NIGHT. HIGH PRESSURE IS FORECAST TO INFLUENCE OUR REGION FROM THURSDAY INTO SATURDAY. A WARM FRONT MAY APPROACH FROM THE SOUTHWEST ON SATURDAY NIGHT AND SUNDAY. AS A RESULT, WE HAVE MENTIONED CHANCE POPS FOR SUNDAY. && .AVIATION /07Z MONDAY THROUGH FRIDAY/... MAINLY CLEAR SKIES ACROSS THE AREA EARLY THIS MORNING. FOG HAS DEVELOPED IN MANY AREAS AND IS EXPECTED TO BECOME THICKER AND MORE WIDESPREAD TOWARD DAWN. UPPER LOW PRESENTLY ACROSS WRN PA CREATED PLENTY OF PROBLEMS AT THE TAF SITES YESTERDAY. THE LOW WILL ROTATE ACROSS THE REGION TODAY. THE INSTABILITY WILL BE LESS THAN SUNDAY AS PLENTY OF CLOUDS ARE EXPECTED TO LIMIT DAYTIME HEATING. SCATTERED SHOWERS AND THUNDERSTORMS ARE STILL POSSIBLE AND WITH THAT IN MIND I HAVE USED VCSH AND CB CLOUD GROUPS TO COVER THE POSSIBILITY FOR ANY CONVECTION TODAY. SFC WINDS WILL BE FROM THE NW (MAINLY) AS THE SFC LOW WILL BE LINGERING ALONG THE NJ COAST. CHANCES FOR RAIN DIMINISH TONIGHT WITH CLOUDS DECREASING LATE. MORE FOG POSSIBLE MON NIGHT. OUTLOOK...TUE THROUGH MOST OF WED SHOULD HAVE MAINLY FAIR WEATHER. WEAK DISTURBANCES WED NIGHT THROUGH THU MAY CREATE SHORT PERIODS OF LOWER CIGS AND VSBYS. && .MARINE... WINDS ARE GENTLE OVER THE WATERS EARLY THIS MORNING WITH DIRECTIONS GENERALLY FROM THE S OR SW. LOW PRESSURE WILL LINGER OVER THE WATERS THIS MORNING AND THEN MOVE TO THE EAST LATER TODAY. WIND DIRECTIONS SHOULD GO W OR NW LATER TODAY AND SPEEDS WILL SLOWLY INCREASE AS THE LOW MOVES AWAY. PRESENT MODEL GUIDANCE DOES NOT CALL FOR WINDS STRONG ENOUGH FOR ANY SCA FLAG, SO I WILL HOLD ON IT FOR NOW. THERE WILL PROBABLY BE GUSTS AROUND 20 KTS THIS EVENING AND TONIGHT HOWEVER. SEAS WILL BE IN THE 2 TO 4 FT RANGE THROUGH TONIGHT. OPERATIONAL MODELS SHOW A LOW PASSING OFF THE CAROLINA COASTAL AREAS WED NIGHT OR EARLY THU. THE GRADIENT ACROSS OUR AREA MAY BECOME STRONG ENOUGH FOR A SCA FLAG THEN. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...NONE. && SYNOPSIS...KRUZDLO NEAR TERM...KRUZDLO SHORT TERM...KRUZDLO LONG TERM...IOVINO AVIATION...OHARA MARINE...OHARA
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 441 AM EDT MON AUG 11 2008 DEZ001-MDZ008-NJZ001-007>010-012>020-026-027-PAZ054-055-060>062- 067>071-120845- NEW CASTLE-CECIL-SUSSEX-WARREN-MORRIS-HUNTERDON-SOMERSET-MIDDLESEX- WESTERN MONMOUTH-EASTERN MONMOUTH-MERCER-SALEM-GLOUCESTER-CAMDEN- NORTHWESTERN BURLINGTON-OCEAN-COASTAL OCEAN-SOUTHEASTERN BURLINGTON- CARBON-MONROE-BERKS-LEHIGH-NORTHAMPTON-CHESTER-MONTGOMERY-BUCKS- DELAWARE-PHILADELPHIA- 441 AM EDT MON AUG 11 2008 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHERN DELAWARE...NORTHEAST MARYLAND...CENTRAL NEW JERSEY...NORTHERN NEW JERSEY...NORTHWEST NEW JERSEY...SOUTHERN NEW JERSEY...EAST CENTRAL PENNSYLVANIA...NORTHEAST PENNSYLVANIA AND SOUTHEAST PENNSYLVANIA. .DAY ONE...TODAY AND TONIGHT ISOLATED THUNDERSTORMS TODAY MAY BE ACCOMPANIED BY HAIL AND GUSTY WINDS. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. DEZ002>004-MDZ012-015-019-020-NJZ021>025-120845- KENT-INLAND SUSSEX-DELAWARE BEACHES-KENT MD-QUEEN ANNES-TALBOT- CAROLINE-CUMBERLAND-ATLANTIC-CAPE MAY-ATLANTIC COASTAL CAPE MAY- COASTAL ATLANTIC- 441 AM EDT MON AUG 11 2008 THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL DELAWARE...SOUTHERN DELAWARE...NORTHEAST MARYLAND AND SOUTHERN NEW JERSEY. .DAY ONE...TODAY AND TONIGHT NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. ANZ450-451-120845- 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- 441 AM EDT MON AUG 11 2008 THIS HAZARDOUS WEATHER OUTLOOK IS FOR ATLANTIC COASTAL WATERS. .DAY ONE...TODAY AND TONIGHT ISOLATED THUNDERSTORMS TODAY MAY BE ACCOMPANIED BY HAIL AND GUSTY WINDS. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. ANZ430-431-452>455-120845- 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 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- 441 AM EDT MON AUG 11 2008 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...TUESDAY THROUGH SUNDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. KRUZDLO
The Philadelphia radar (KDIX), 130 km away, was scanning. The volume nearest the first event began at 12:48 UTC.
1 lightning. Local standard time, as filed.
A lightning strike split the chimney of a shed on Poplar Street in Reading. Pieces of the chimney fell onto a car that was being parked. The driver was not hurt.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2008Every state in 2008This day in weather historyWarnings in Pennsylvania, August 2008
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: 132044.