Pennsylvania, 2001

Heat in Pennsylvania, July 1, 2001

July 1, 2001 · NWS PHI · 5 events in 5 counties and zones

A large ridge of high pressure both at the surface and aloft along the western Atlantic Ocean produced six consecutive days of heat and increasing humidity across southeastern Pennsylvania from June 26th through July 1st. A cold front broke the excessive heat with strong to severe thunderstorms on July 1st.

Where it happened

Every event with a place to put it; 2 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

  • Tornadoes
  • Tropical storms and surge
  • Floods
  • Wind
  • Hail
  • Winter weather
  • Heat and drought
  • Cold
  • Fire, smoke and dust
  • Marine and coastal
  • Other

Open the live radar over this ground

The toll

Deaths
1
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
5

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.

What happened

The episode as NWS PHI wrote it up.

A large ridge of high pressure both at the surface and aloft along the western Atlantic Ocean produced six consecutive days of heat and increasing humidity across southeastern Pennsylvania from June 26th through July 1st. A cold front broke the excessive heat with strong to severe thunderstorms on July 1st. High temperatures reached into the mid 90s and combined with the humid air mass produced afternoon heat indices of around 100 degrees. There were three heat related deaths (two in June and one in July). A 70-year-old woman, a 58-year-old man and a 77 year-old woman all perished because of the heat in Philadelphia. June 28th and 30th were the hottest days for most locations. Highest temperatures included 97 degrees at the Franklin Institute within Philadelphia, 96 degrees in Perkasie (Bucks County) and West Chester (Chester County), 94 degrees at the Philadelphia International Airport, 93 degrees at the Northeast Philadelphia Airport and 91 degrees in Doylestown (Bucks County) and Pottstown (Montgomery County).

What forecasters said that day

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 Jun 30, 9:00 PM EST, 3 hours earlier.

Area forecast discussion, Jun 30, 9:00 PM EST, 3 hours before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1000 PM EDT SAT JUN 30 2001

STILL HAVE SOME SHWRS/TSTMS SLIDING E THRU THE FCST AREA...AND
WATCHING ACTVTY WELL TO THE W WHICH COULD MOVE IN LTR IF IT HOLDS
TOGETHER. OTRW...KEEPING ZONES PRETTY MUCH THE SAME AS THEY ARE NOW.

.PHI...URBAN HEAT WRNG THRU SUN PA67-71 NJ15/17-19 DE1
       HEAT ADVY THRU SUN NJ16/21-23 MD8/12/15/19/20 DE2-3

KRAUS

In the hours before

Local storm report, Jun 30, 8:49 PM EST, 3 hours 11 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MOUNT HOLLY/NEW JERSEY
949 PM EDT SAT JUN 30 2001

TIME(EDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0130 PM    ISLAND BEACH              NJ   LIGHTNING
06/30/01   OCEAN                          *** 1 DEAD ***
                                          23-YEAR-OLD MALE STRUCK
                                          AND KILLED BY LIGHTNING ON
                                          ISLAND BEACH STATE PARK

0630 PM    ROCK HALL                 MD   WIND DAMAGE
06/30/01   KENT                           PADDLE BOATS AND KAYAKS
                                          OVERTURNED FROM ROCK HALL
                                          SOUTHWARD. SEVERAL WATER
                                          RESCUES.

0645 PM    QUEENSTOWN                MD   WIND DAMAGE
06/30/01   QUEEN ANNES                    WIRES PULLED DOWN ACROSS
                                          THE SOUTHERN PART OF THE
                                          COUNTY.

0700 PM    MORRISTOWN                NJ   WIND DAMAGE
06/30/01   MORRIS                         FEW TREES DOWN IN
                                          MORRISTOWN. ONE TREE
                                          DAMAGED A HOME.

0710 PM    DENTON                    MD   WIND DAMAGE
06/30/01   CAROLINE                       NUMEROUS TREES DOWN IN THE
                                          COUNTY. DENTON HARDEST HIT.
                                          HAIL ALSO FELL. SIZE
                                          UNKNOWN.

0745 PM    DOYLESTOWN                PA   WIND DAMAGE
06/30/01   BUCKS                          NUMEROUS LARGE LIMBS DOWN
                                          ACROSS THE CENTRAL PART OF
                                          THE COUNTY. REPORT OF A
                                          FUNNEL CLOUD REPORTED NEAR
                                          CHALFONT.

0850 PM    PERKASIE                  PA
06/30/01   BUCKS                          THUNDERSTORM WIND GUST
                                          ESTIMATED AT 40 MPH.
                                          BRANCHES DOWN. POSSIBLE
                                          FUNNEL. CONSIDERABLE
                                          LIGHTNING. DOPPLER RADAR
                                          STORM TOTAL ESTIMATES
                                          AROUND 3 INCHES AROUND
                      ]                    AREA.

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

5 heat. Local standard time, as filed.

Heat, Bucks

When
July 1, 12:00 AM EST to 6:00 PM EST
Where
Bucks forecast zone
Reported by
AWOS,ASOS,MESONET,ETC

Heat, Chester

When
July 1, 12:00 AM EST to 6:00 PM EST
Where
Chester forecast zone
Reported by
AWOS,ASOS,MESONET,ETC

Heat, Delaware

When
July 1, 12:00 AM EST to 6:00 PM EST
Where
Delaware forecast zone
Reported by
AWOS,ASOS,MESONET,ETC
Coordinates
39.917, -75.399 (the zone’s center; the record gives no point)

Heat, Montgomery

When
July 1, 12:00 AM EST to 6:00 PM EST
Where
Montgomery forecast zone
Reported by
AWOS,ASOS,MESONET,ETC

Heat, Philadelphia

When
July 1, 12:00 AM EST to 6:00 PM EST
Where
Philadelphia forecast zone
Deaths
1 direct, 0 indirect
Reported by
AWOS,ASOS,MESONET,ETC
Coordinates
40.008, -75.134 (the zone’s center; the record gives no point)

The people who died

As the offices recorded each death: direct deaths were caused by the weather itself, indirect ones by something it set in motion.

EventDateAgeSexWhereKind
Heat, Philadelphia2001-07-0377FemalePermanent HomeDirect

What these are

Heat
Heat below excessive heat criteria that still caused deaths, injuries or significant impacts.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in Pennsylvania in 2001Every state in 2001This day in weather historyWarnings in Pennsylvania, July 2001

Sources

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: 5260072, 5260073, 5260074, 5260075, 5260076.