A thunderstorm with torrential downpours formed along the warm frontal boundary in Berks County during the evening of the 23rd.
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.
A thunderstorm with torrential downpours formed along the warm frontal boundary in Berks County during the evening of the 23rd.
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 May 23, 8:31 PM EST, 29 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 931 PM EDT SAT MAY 23 2009 .SYNOPSIS... A WEAK FRONT ACROSS THE FORECAST AREA WILL MOVE NORTH AS A WARM FRONT TONIGHT. A COLD FRONT OVER THE GREAT LAKES WILL MOVE SLOWLY SOUTHEAST AND START PASSING THROUGH THE FORECAST AREA ON SUNDAY AND CLEAR SOUTHERN DELAWARE ON MONDAY. THIS FRONT WILL STALL MONDAY NIGHT NEAR VIRGINIA BEFORE IT TOO STARTS MOVING BACK AS A WARM FRONT TUESDAY INTO WEDNESDAY. A COLD FRONT SHOULD THEN MOVE THROUGH THE MIDDLE ATLANTIC STATES LATE THURSDAY OR FRIDAY. HIGH PRESSURE SHOULD THEN START BUILDING INTO THE REGION FOR NEXT WEEKEND. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... THE LINGERING FRONTAL SYSTEM HAS FIRED SOME SHOWERS AND THUNDERSTORMS THROUGH THE EVENING AND EVEN NOW AFTER SUNSET, THEY ARE STILL DEVELOPING OVER BERKS COUNTY. LIGHTNING ACTIVITY IS HIGH WITH THE THUNDERSTORMS AND STRIKE COUNTS OF 50 OR SO IN A 5 MINUTE PERIOD PRESENTLY OVER ERN BERKS COUNTY. A DECENT SOUTHERLY FLOW OF MILD AND HUMID AIR CONTINUES OVER SOUTHERN PA. THIS AIR IS RISING OVER THE HILLY TERRAIN OF PA AND CAUSING THE ACTIVITY TO CONTINUE. THERE IS LITTLE IF ANY UPPER DYNAMICS PROMOTING THE ACTIVITY, SO NO SVR WEATHER IS EXPECTED OVERNIGHT. THE 18Z RUN OF THE WRF SHOWS ACTIVITY CONTINUING ACROSS BERKS COUNTY AND THE LEHIGH VALLEY OVERNIGHT, SO CHC POPS HAVE BEEN RETAINED FROM EARLIER AND EXTENDED INTO THE OVERNIGHT. AN AREA OF FOG PERSISTS OFF THE NORTHERN NJ SHORE AREAS, SO IT ALSO HAS BEEN LEFT IN THERE WITH THE UPDATE. ZONES/AFM/PFM ALREADY ISSUED. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/... THE APPROACHING COLD FRONT ON SUNDAY SHOULD PROVIDE A TRIGGERING MECHANISM FOR FURTHER CONVECTION. UNLIKE TODAY IT APPEARS THAT THE THERMODYNAMICS AND KINEMATICS SHOULD BE BETTER ALIGNED. THE OVERALL ENVIRONMENTAL WINDS ARE FCST TO BE WEAKER, BUT THE NORTHERN PART OF OUR CWA WILL BE CLOSER TO THE EXIT REGION OF THE H250 JET AND ALSO IN AN AREA OF POSITIVE MID LVL QVEC CONVERGENCE. A COUPLE OF WEAK SHORT WAVES ARE FCST TO MOVE THRU THIS REGION. OVERALL THERE APPEARS ENOUGH OF A TRIGGERING SUPPORT. THE QUESTION REMAINS WHETHER OR NOT THE 2000J OF FCST CAPE CAN THRIVE IN A RELATIVELY WEAK SHEARED ENVIRONMENT AND FCST MID LVL LAPSE RATES THAT ARE PATHETIC. THE ONE FAVORABLE FEATURE IS THAT THE FCST DROP OF THETA E WITH HEIGHT IS ABOUT 20C AND THAT IS WITHIN THE PULSE SVR TSRA RANGE. ALSO USING 20KT AS THE EFFECTIVE CUT OFF OF SHEAR FOR SVR VS NON SVR DOES PLACE THE NORTHERN PART OF OUR CWA BARELY WITHIN RANGE. AGREE WITH THE SEE TEXT APPROACH THAT SPC HAS ISSUED FOR DAY2 UPSHOT WE WILL UP POPS TO LIKELY ACROSS THE NORTHERN PART OF OUR CWA WHERE ALL OF THESE PARAMETERS GET STACKED AND IS ALSO COINCIDENTAL WITH THE FCST 850MB THETA E RIDGE ON BOTH THE GFS AND WRF-NMM. BECAUSE OF ANY OTHER SUPPORT FEATURES WE HAVE SCALED BACK THE MENTION OF TSRA MORE AND MORE TO THE SOUTH. WE HAVE TRIED TO INCLUDE SOME OF THE ONGOING RESEARCH WORK BY DR PAUL CROFT ABOUT INITIATIVES TO CONVECTION IN W OR NW FLOW IN JUNE (OK ITS STILL MAY). THIS FAVORS OUR HIGHER TERRAIN LOCATIONS AND CONVERSELY THE FLOW WOULD NOT TAKE IT INTO THE SOUTHERN PART OF OUR CWA DURING THE DAY ON SUNDAY. MOS GUIDANCE HAS BEEN A BIT LOW WITH MAX TEMPS AND WE WILL BE GOING ABOVE THEM ON SUNDAY. FOR SUNDAY NIGHT AND MONDAY COULD SEE A PCPN SHAFT ZONE THAT INCLUDES PART OF THE LOCAL PHL METRO AREA. THE SERIES OF SHORT WAVES ARE FCST TO REMAIN NORTH SO THE SOUTHWARD EXTENT OF PCPN WILL DEPEND UPON HOW ORGANIZED THE CONVECTION CAN GET GOING DURING THE DAY ON SUNDAY. AS IT IS WE TRIED TO CONVEY A MORE EWD THAN SWD SAG OF HIGHEST PCPN CHCS FOR SUNDAY NIGHT. ON MONDAY THE LATEST MODEL GUIDANCE IS SHOWING IT TOO STABLE FOR THUNDER ALTHOUGH SOME UNDER-RUNNING SHRAS MIGHT OCCUR TO THE NORTH OF THE SHALLOWING COLD FRONT. WE KEPT THE MENTION OF THUNDER IN FOR NOW TO SEE IF THIS TREND CONTINUES. WE KEPT A LITTLE NORTHWARD LEE-WAY OF PCPN CHANCES INTO THE PHL METRO PENDING THE FRONTAL MOVEMENT, BUT THERE IS ENOUGH OF MODEL CONSENSUS AND TREND TO REMOVE POPS FAR N. GOING TO COMPROMISE BTWN THE MOS DATASETS FOR MINS AND MAX TEMPS SUN NGT AND MON. THE GFS IS OFTEN TOO FAST EVEN IF ITS INITIALIZATION IS GOOD. && .LONG TERM /TUESDAY THROUGH SATURDAY/... UNSETTLED WEATHER REMAINS THE KEY FOR THIS OUTLOOK PERIOD. EMERGING FROM A RELATIVELY DRY PATTERN, WE WILL BE GETTING WET AGAIN. AN OVERRUNNING RAIN APPEARS LIKELY FOR TUESDAY INTO EARLY WEDNESDAY. AS A WARM FRONT WILL START LIFTING TOWARD OUR CWA AND HIGH PRESSURE SLIDES OFF OF NEW ENGLAND. RIGHT NOW CONVECTIVE PARAMETERS ARE NOT FAVORING ANY THUNDER AS THIS WARM FRONT LIFTS NORTHWARD. WEDNESDAY AND WEDNESDAY NIGHT SHOULD FEATURE A NORTH TO SOUTH POP GRADIENT AS THE FRONTAL BOUNDARY IS EXPECTED TO LIFT NORTH INTO NEW ENGLAND WITH OUR LOWEST CHANCES IN DELMARVA. THERE IS DECENT MODEL CONSENSUS FOR THURSDAY TO BE THE CENTERPIECE OF THE NEXT ENHANCED CHANCE FOR PRECIPITATION AND DEPENDING UPON THE COLD FRONTAL POSITION COULD BE QUITE CONVECTIVELY ACTIVE. AS AN EXAMPLE SOME GFS RUNS HAVE FCST LIFTED INDICES OF -8C. FRIDAY WILL DEPEND UPON HOW QUICKLY THE FRONT MOVES THROUGH OUR CWA, WE ARE CURRENTLY OPTING FOR THE SLOWER ECMWF SOLUTION AND NEXT SATURDAY AS OF NOW APPEARS DRY. TUESDAY COULD BE RELATIVELY CHILLY BY LATE MAY STANDARDS, BUT AS WE EMERGE IN THE WARM SECTOR, WEDNESDAY AND ESPECIALLY THURSDAY HAVE THE POTENTIAL TO BE WARMER THAN THE 00Z GFS MOS GUIDANCE HAD. WE MIGHT BE IN ANOTHER DIURNAL PATTERN WHERE 00Z GFS MOS IS TOO LOW, BUT 12Z MOS APPEARS MORE REPRESENTATIVE. OPTING FOR THE SLOWER SOLUTION WE ARE WARMER THAN GFS MOS FOR FRIDAY AND THEN DID NOT STRAY MUCH FROM GFS MOS GUIDANCE SATURDAY. && .AVIATION /01Z SUNDAY THROUGH THURSDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. ONCE THE THUNDERSTORM ACTIVITY MOVES BY KABE SHORTLY, SKIES SHOULD IMPROVE TO PARTLY CLOUDY CONDITIONS. AREAS OF FOG MAY DEVELOP OVER KRDG, KABE AND KMIV OVERNIGHT WITH MVFR POSSIBLE. MORE SHOWERS AND SCATTERED THUNDERSTORMS SHOULD DEVELOP IN THE HEAT OF THE DAY SUNDAY WITH THE BETTER CHANCES ARRIVING AFTER 18Z OR SO. OUTLOOK... A COLD FRONT APPROACHING FROM THE NORTHWEST IS FORECAST TO TOUCH OFF SCATTERED TO SHOWERS AND THUNDERSTORMS SUNDAY INTO SUNDAY NIGHT. THE ACTIVITY COULD BE JUST ABOUT ANYTIME SUNDAY IN OUR NORTHERN AREAS, BUT SHOULD NOT REACH SOUTHERN SECTIONS UNTIL LATER IN THE DAY. THE FRONT IS EXPECTED TO CROSS OUR AREA SUNDAY NIGHT, DROPPING FURTHER SOUTH ON MONDAY. THIS WILL LIKELY SUPPRESS ANY CONVECTION TO OUR SOUTHERN SECTIONS, AND POSSIBLY PUSH IT EVEN FARTHER TO OUR SOUTH AND OUT OF OUR AREA FOR A PERIOD OF TIME. BUT FOR TUESDAY INTO WEDNESDAY THERE COULD BE A MORE PROLONGED RAIN AS A WARM FRONT MOVES OVER THE REGION. RESTRICTIONS TO CIGS AND VSBYS ARE LIKELY DURING THIS TIME PERIOD. && .MARINE... AREAS OF FOG WILL CONTINUE TO AFFECT THE WATERS ADJACENT TO OCEAN AND MONMOUTH COUNTIES OF NJ. COMPUTER MODELS CONTINUE TO INDICATE THAT A STALLED FRONT ACROSS THE AREA WILL BEGIN TO PUSH BACK NORTH LATER TONIGHT. THIS WILL ONCE AGAIN SWING WINDS BACK AROUND TO A SOUTHERLY DIRECTION AND SHOULD PUSH THE FOG BANK BACK OFF THE COAST AND OUT TO SEA. WITH RELATIVELY LIGHT WINDS AND SMALL SEAS, THE HOLIDAY WEEKEND CONTINUES TO BE A GOOD ONE FOR THE BOATING COMMUNITY. THESE CONDITIONS SHOULD CONTINUE INTO SUNDAY. A COLD FRONT APPROACHING FROM THE NORTHWEST WILL BRING THE THREAT OF SHOWERS/TSTMS SUNDAY AFTERNOON INTO SUNDAY NIGHT. THE THREAT WILL BE INCREASING FROM NORTH TO SOUTH. SOUTHERN SECTIONS MAY NOT SEE ANY SHOWER/TSTM ACTIVITY UNTIL THE EVENING HOURS OR, POSSIBLY, SUNDAY NIGHT. THE FRONT IS EXPECTED TO DROP JUST TO OUR SOUTH ON MONDAY. THERE STILL COULD BE SOME SHOWERS/TSTMS FOR OUR FAR SOUTHERN AREAS, BUT MOST AREAS SHOULD BE PRECIPITATION FREE. THE FRONT IS THEN EXPECTED TO MOVE BACK ACROSS OUR WATERS AS A WARM FRONT LATE TUESDAY OR TUESDAY NIGHT, CAUSING WINDS TO BECOME SOUTHERLY ONCE AGAIN. A STRONG COLD FRONT IS THEN FORECAST TO CROSS OUR AREA THURSDAY NIGHT OR EARLY FRIDAY. WINDS AND/OR SEAS COULD REACH SMALL CRAFT ADVISORY CRITERIA LATE TUESDAY INTO THURSDAY NIGHT OR FRIDAY. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...NONE. && SYNOPSIS...GIGI NEAR TERM...OHARA SHORT TERM...GIGI LONG TERM...GIGI AVIATION...OHARA/RPW MARINE...RPW/OHARA
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 451 AM EDT SAT MAY 23 2009 DEZ001>003-MDZ008-012-015-019-020-NJZ001-007>010-012>027-PAZ054-055- 060>062-067>071-240900- NEW CASTLE-KENT-INLAND SUSSEX-CECIL-KENT MD-QUEEN ANNES-TALBOT- CAROLINE-SUSSEX-WARREN-MORRIS-HUNTERDON-SOMERSET-MIDDLESEX- WESTERN MONMOUTH-EASTERN MONMOUTH-MERCER-SALEM-GLOUCESTER-CAMDEN- NORTHWESTERN BURLINGTON-OCEAN-CUMBERLAND-ATLANTIC-CAPE MAY- ATLANTIC COASTAL CAPE MAY-COASTAL ATLANTIC-COASTAL OCEAN- SOUTHEASTERN BURLINGTON-CARBON-MONROE-BERKS-LEHIGH-NORTHAMPTON- CHESTER-MONTGOMERY-BUCKS-DELAWARE-PHILADELPHIA- 451 AM EDT SAT MAY 23 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL DELAWARE...NORTHERN DELAWARE...SOUTHERN 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. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. ANZ430-431-450>455-DEZ004-240900- 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- DELAWARE BEACHES- 451 AM EDT SAT MAY 23 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR ATLANTIC COASTAL WATERS...SOUTHERN DELAWARE AND DELAWARE BAY WATERS. .DAY ONE...TODAY AND TONIGHT. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.
SPECIAL WEATHER STATEMENT...CORRECTED NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 630 PM EDT SAT MAY 23 2009 NJZ013-014-020-026-240130- WESTERN MONMOUTH-EASTERN MONMOUTH-OCEAN-COASTAL OCEAN- INCLUDING THE CITIES OF...FREEHOLD...SANDY HOOK...JACKSON... LONG BEACH ISLAND 630 PM EDT SAT MAY 23 2009 ...DENSE FOG BANK ON THE NORTHERN COASTAL WATERS OF NEW JERSEY... A DENSE FOG BANK REMAINED OVER THE NORTHERN COASTAL WATERS OF NEW JERSEY EARLY THIS EVENING. AT 620 PM, THE DENSE FOG WAS AFFECTING THE WATERS OFF THE COAST FROM AROUND SEASIDE HEIGHTS UP TO SANDY HOOK, AS WELL AS ADJACENT COASTAL COMMUNITIES. THE FOG BANK WILL CONTINUE TO DRIFT NORTHWARD DURING THE EVENING, WITH IMPROVING CONDITIONS WORKING THEIR WAY UP FROM THE SOUTH. THE FOG MAY REDUCE THE VISIBILITY TO NEAR ZERO AT TIMES. IOVINO
PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
706 PM EDT SAT MAY 23 2009
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0400 PM LIGHTNING BATH 40.73N 75.39W
05/23/2009 NORTHAMPTON PA NEWSPAPER
SEVERAL STRUCTURE FIRES IN BATH AND MOORE TOWNSHIP DUE TO
LIGHTNING.
0430 PM HAIL 2 NNE LEHIGH UNIVERSITY 40.63N 75.37W
05/23/2009 M1.00 INCH NORTHAMPTON PA TRAINED SPOTTER
QUARTER SIZE HAIL IN BETHLEHEM TOWNSHIP.
0437 PM HAIL 2 WNW WILSON 40.70N 75.28W
05/23/2009 M0.75 INCH NORTHAMPTON PA PUBLIC
PENNY SIZE HAIL REPORTED BY A METEOROLOGIST IN PALMER
TOWNSHIP.
0447 PM HAIL PHILLIPSBURG 40.69N 75.18W
05/23/2009 M1.00 INCH WARREN NJ TRAINED SPOTTER
QUARTER SIZE HAIL.
0452 PM HAIL ALPHA 40.66N 75.16W
05/23/2009 M0.75 INCH WARREN NJ TRAINED SPOTTER
PENNY SIZE HAIL IN ALPHA.
&&SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 811 PM EDT SAT MAY 23 2009 PAZ060-061-240115- BERKS-LEHIGH- INCLUDING THE CITIES OF...READING...ALLENTOWN 811 PM EDT SAT MAY 23 2009 ...STRONG THUNDERSTORMS TO AFFECT PARTS OF BERKS COUNTY AND LEHIGH COUNTY... AT 810 PM, NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED STRONG THUNDERSTORMS OVER NORTHERN BERKS COUNTY BETWEEN BERNVILLE, HAMBURG AND KUTZTOWN. THE THUNDERSTORMS WERE MOVING NORTHEAST AROUND 10 MPH, AND THEY SHOULD AFFECT THE NORTH CENTRAL AND NORTHEASTERN PARTS OF BERKS COUNTY AND THE WESTERN PART OF LEHIGH COUNTY BEFORE 900 PM. VERY HEAVY RAIN WILL FALL FROM THESE STORMS, AND IT WILL CAUSE WATER TO POND ON ROADS AND QUICKLY FILL ROADSIDE DITCHES AND SMALL STREAMS. WIND GUSTS TO 40 MPH AND SMALL HAIL ARE POSSIBLE WITH THESE STORMS. EXPECT NUMEROUS CLOUD TO GROUND LIGHTNING STRIKES. DO NOT SEEK SHELTER UNDER A TREE WHEN LIGHTNING THREATENS. MOVE INDOORS WHEN A THUNDERSTORM APPROACHES. IOVINO
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 841 PM EDT SAT MAY 23 2009 PAZ060>062-240145- BERKS-LEHIGH-NORTHAMPTON- INCLUDING THE CITIES OF...READING...ALLENTOWN...BETHLEHEM... EASTON 841 PM EDT SAT MAY 23 2009 ...STRONG THUNDERSTORMS TO AFFECT PARTS OF BERKS...LEHIGH AND NORTHAMPTON COUNTIES... AT 840 PM, NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED STRONG THUNDERSTORMS OVER NORTHEASTERN BERKS COUNTY AND LEHIGH COUNTY. THE THUNDERSTORMS WERE MOVING NORTHEAST AROUND 10 MPH, AND THEY SHOULD CONTINUE TO AFFECT NORTHEASTERN BERKS COUNTY AND THE LEHIGH VALLEY UNTIL AT LEAST 930 PM. VERY HEAVY RAIN WILL FALL FROM THESE STORMS, AND IT WILL CAUSE WATER TO POND ON ROADS AND QUICKLY FILL ROADSIDE DITCHES AND SMALL STREAMS. WIND GUSTS TO 40 MPH AND SMALL HAIL ARE POSSIBLE WITH THESE STORMS. EXPECT NUMEROUS CLOUD TO GROUND LIGHTNING STRIKES. DO NOT SEEK SHELTER UNDER A TREE WHEN LIGHTNING THREATENS. MOVE INDOORS WHEN A THUNDERSTORM APPROACHES. IOVINO
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 918 PM EDT SAT MAY 23 2009 PAZ060-240230- BERKS- INCLUDING THE CITY OF...READING 918 PM EDT SAT MAY 23 2009 ...ADDITIONAL STRONG THUNDERSTORMS DEVELOPING OVER BERKS COUNTY... AT 915 PM, NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED STRONG THUNDERSTORMS DEVELOPING OVER WESTERN AND SOUTHERN BERKS COUNTY. THE THUNDERSTORMS WERE STRENGTHENING WHILE MOVING TO THE NORTHEAST AROUND 10 MPH. ANOTHER LINE OF STRONG THUNDERSTORMS WAS LOCATED OVER THE NORTHEASTERN PART OF THE COUNTY. THE LINE OF STORMS WAS CONTINUING TO SHOW SIGNS OF WEAKENING. VERY HEAVY RAIN WILL FALL FROM THESE STORMS, AND IT WILL CAUSE WATER TO POND ON ROADS AND QUICKLY FILL ROADSIDE DITCHES AND SMALL STREAMS. WIND GUSTS TO 40 MPH AND SMALL HAIL ARE POSSIBLE WITH THESE STORMS. EXPECT NUMEROUS CLOUD TO GROUND LIGHTNING STRIKES. DO NOT SEEK SHELTER UNDER A TREE WHEN LIGHTNING THREATENS. MOVE INDOORS WHEN A THUNDERSTORM APPROACHES. IOVINO
PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
925 PM EDT SAT MAY 23 2009
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0400 PM LIGHTNING BATH 40.73N 75.39W
05/23/2009 NORTHAMPTON PA NEWSPAPER
SEVERAL STRUCTURE FIRES IN BATH AND MOORE TOWNSHIP DUE TO
LIGHTNING.
0430 PM HAIL 2 NNE LEHIGH UNIVERSITY 40.63N 75.37W
05/23/2009 M1.00 INCH NORTHAMPTON PA TRAINED SPOTTER
QUARTER SIZE HAIL IN BETHLEHEM TOWNSHIP.
0437 PM HAIL 2 WNW WILSON 40.70N 75.28W
05/23/2009 M0.75 INCH NORTHAMPTON PA PUBLIC
PENNY SIZE HAIL REPORTED BY A METEOROLOGIST IN PALMER
TOWNSHIP.
0447 PM HAIL PHILLIPSBURG 40.69N 75.18W
05/23/2009 M1.00 INCH WARREN NJ TRAINED SPOTTER
QUARTER SIZE HAIL.
0452 PM HAIL ALPHA 40.66N 75.16W
05/23/2009 M0.75 INCH WARREN NJ TRAINED SPOTTER
PENNY SIZE HAIL IN ALPHA.
0855 PM LIGHTNING 2 E TOPTON 40.50N 75.66W
05/23/2009 BERKS PA TRAINED SPOTTER
HOUSE STRUCK BY LIGHTNING IN MERTZTOWN.
&&The Philadelphia radar (KDIX), 137 km away, was scanning. The volume nearest the first event began at 02:00 UTC.
1 flash flood. Local standard time, as filed.
Thunderstorms with heavy downpours caused flooding in and around Richmond Township in Berks County. Roads were flooded and closed in the area. Doppler Radar storm total estimates reached between 2.5 and 3.0 inches, most of which fell within one hour.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Pennsylvania in 2009Every state in 2009This day in weather historyWarnings in Pennsylvania, May 2009
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: 168934.