Flood, Lehigh
- When
- June 20, 7:00 PM EST to June 21, 6:30 AM EST
- Where
- Lehigh forecast zone
- Reported by
- AWOS,ASOS,MESONET,ETC
- Coordinates
- 40.613, -75.592 (the zone’s center; the record gives no point)
Flood in Pennsylvania, June 20 to 21, 2003
A slow moving low pressure system at both the surface and aloft helped trigger heavy rain across Lehigh County. 5 inches.
Where it happened
Every event with a place to put it; 1 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
The toll
- Deaths
- 0
- Injuries
- 0
- Property damage
- None recorded
- Crop damage
- None recorded
- Events
- 1
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 slow moving low pressure system at both the surface and aloft helped trigger heavy rain across Lehigh County. Storm totals averaged around 2.5 inches. The heavy rain led to poor drainage flooding and flooding of streams and rivers in the county. In Salisbury Township, the flooding of the Little Lehigh River closed one road. In Allentown, Cedar Creek and Lake Muhlenberg overflowed. Seven blocks were closed. In Lower Macungie Township, flooding along the Swabia Creek forced a bridge closure. Several vehicles throughout the county became trapped in flood waters. The Little Lehigh River in Allentown was above its 6 foot flood stage from 1058 p.m. EDT on the 20th through 347 a.m. EDT on the 21st. It crested at 6.8 feet at 115 a.m. EDT on the 21st. The Lehigh River at Walnutport (along the Northampton County border) reached and stayed at its 8 foot flood stage from 630 a.m. EDT through 730 a.m. EDT on the 21st. Storm totals included 2.67 inches at the Lehigh Valley International Airport. The low pressure system responsible for the heavy rain formed along a stationary front over the Carolinas during the morning of the 20th. It moved to just east of Wallops Island, Virginia during the evening of the 20th and well east of the Delmarva Peninsula during the morning of the 21st. An inverted trough at the surface that extended from the low north into Chesapeake Bay and Eastern Pennsylvania concentrated the heavy rain along its axis. June as a whole was an unseasonably wet month. On a county weighted average, June monthly precipitation totals averaged 9.1 inches in Lehigh County. Normal is around 3.9 inches. The June monthly precipitation total of 8.30 inches at the Lehigh Valley International Airport was the third wettest on record. The wet spring weather led to a whole different set of problems from the drought of the previous year. Planted seeds were drowning and rotting. Many soybean, corn and berry fields were too wet. There were also problems with slugs. Vegetables were generally about a month behind. Double crop fields fell behind schedule because of the slow growth of straw and hay. Garden shops sales have been down. Pool installations were about three to six weeks behind. Ant infestations increased. Windshield wipers were tearing. Many spring athletic seasons were extended because of postponed events. There will be a bumper crop of mosquitoes. Attendance along the shore and at amusement parks was down. Road work was delayed. The one few positives from the wet weather was lower utility bills.
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 20, 2:45 PM EST, 4 hours 15 minutes earlier.
Area forecast discussion, Jun 20, 2:45 PM EST, 4 hours 15 minutes before
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 345 PM EDT FRI JUN 20 2003 DISC: BY LOCAL EXCSSV RAINFALL CHECKLIST STANDARDS...WE CAME UP SHRT FOR WATCH CRITERIA...HOWEVER...GIVEN THE STATE OF THE GROUND(SINCE OCT) AND THE PROLONGED EVENT WE ARE IN SOME AREAS WILL EXPERIENCE FLOODING ESP WHERE CONVECTION OCCURS OVER OUR FLASHY BASINS. THE 12Z RUNS HAVE COME TOGETHER AS FAR AS THE 3-4 INCH BULLSEYE BUT THE ETA GIVES US LESS THIS RUN THAN EARLIER AND HAS SHIFTED THE MAX AMNTS FROM SNJ TO LEHIGH VALLEY PER GFS. BEING A PROLONGED EVENT IS FAVORABLE FOR REDUCING FLOODING ON LARGER RIVERS/STREAMS BUT SOME ISOLATED CONV LIKELY TO SEND SMALLER ONES TO OR OVER FS. THANKS TO MARFC FOR DETAILED COOR THIS MRNG. WITH THE HIGHER QPF ANTICIPATED TO BE ACROSS THE LEHIGH VALLEY AND INTO NW NJ...THE FLD WATCH HAS BEEN SHAVED BACK ACROSS THE SOUTH. THE HIGHER TERRAIN IN NE PA AND NW NJ WILL BE MORE FAVORABLE FOR HEAVIER RAIN DUE TO TERRAIN ENHANCEMENT ALONG W/ A POSSIBLE DEFORMATION ZONE. THIS ALSO LINES UP WELL WITH MORE UPWARD MOTION IN THE MODELS. PCPN CURRETNLY OVER THE REGION IN RESPONSE TO S/W RACING THRU WRN PA ATTM. 700MB LOW OVER PIT HANDELD BEST BY ETA TRACKS TO THE SE WITH MAX PCPN PIVOTING NE THRU NRN NJ/ERN PA IN TIME WHILE CONSIDERABLY LESS PCPN OVER SRN AREAS. SOME LIGHTER PCPN DEVELOPING ON BACK SIDE OF LWR IN ERN OHIO. PLEASE CHECK LATEST FFWS ISSUED THIS AFTERNOON FOR SOME SE PA/NRN DE STREAMS ALREADY REACHING FS. TIDAL DEPARTURES CONSISTENLY 1-1.5 FT ABV NRM NEXT 48 HRS BUT AT A LOW ATSTRONOMICAL PERIOD ALTHO THE BACK BAYS MAY LOOK A LITTLE HIGH TO SOME. DRYING WILL TAKE PLACE FROM LATE SUN ON AS UPPER RIDGE BUILDS ACROSS THE MID ATLANTIC BUT SHORT LIVED AS COUPLE OF FAST MOVING FRONTS PASS THROUGH THE AREA WITH SHOWER TYPICAL SUMMERTIME PCPN POSSIBLE. TEMPS ALSO LIKELY TO REACH INTO THE MID/UPPER 80S WITH A SHOT AT 90. WOODY - YOUR $S IN THE MAIL FCSTID = 16 MPO 59 66 58 76 / 90 90 70 30 ABE 62 68 60 78 / 90 80 70 30 RDG 62 68 60 78 / 90 80 70 30 PHL 64 70 62 78 / 80 70 70 30 12N 59 66 58 76 / 90 90 70 30 SMQ 61 69 60 77 / 90 90 70 30 TTN 61 69 60 77 / 90 90 70 30 MIV 61 68 60 77 / 80 70 70 30 ACY 62 65 61 74 / 80 70 70 30 ILG 62 70 61 78 / 80 70 70 30 DOV 61 69 61 78 / 80 70 70 30 GED 61 69 61 78 / 80 70 70 30 ESN 61 69 61 78 / 80 70 70 30 .PHI... DE...FLOOD WATCH FOR TONIGHT THROUGH SATURDAY NIGHT FOR ZONE DEZ001. MD...FLOOD WATCH FOR TONIGHT THROUGH SATURDAY NIGHT FOR ZONE MDZ008. NJ...FLOOD WATCH FOR TONIGHT THROUGH SATURDAY NIGHT FOR ZONES NJZ001...NJZ007>010...NJZ012>019. PA...FLOOD WATCH FOR TONIGHT THROUGH SATURDAY NIGHT FOR ZONES PAZ054>055...PAZ060>062...PAZ067>071. EBERWINE/GORSE
Hazardous weather outlook, Jun 20, 4:50 AM EST, 14 hours 10 minutes before
DEZ001>004-MDZ008-012-015-019-020-NJZ001-007>010-012>027-PAZ054-055- 060>062-067>071-201200- HAZARDOUS WEATHER OUTLOOK...UPDATED NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 550 AM EDT FRI JUN 20 2003 THIS HAZARDOUS WEATHER OUTLOOK IS FOR EAST CENTRAL AND SOUTHEAST PENNSYLVANIA...DELAWARE...THE NORTHERN MARYLAND EASTERN SHORE...AND NEW JERSEY EXCLUDING THE FIVE NORTHEAST COUNTIES. .DAY ONE...TODAY A FLOOD WATCH IS IN EFFECT FOR THE ENTIRE AREA TODAY AND TONIGHT. RAIN...HEAVY AT TIMES...COULD PRODUCE FLOODING ESPECIALLY ALONG SMALL STREAMS AND CREEKS...IN URBAN AREAS..AND IN POOR DRAINAGE LOCATIONS. SEE FLOOD WATCH STATEMENT UNDER WMO HEADER /WGUS61 KPHI/ FOR MORE DETAILS. THERE IS A LOW TO OCCASIONALLY MODERATE RISK FOR RIP CURRENTS TODAY DURING RISING TIDE ALONG THE NEW JERSEY AND DELAWARE COASTS. .DAYS TWO THROUGH SEVEN... THE FLOOD WATCH WILL CONTINUE SATURDAY. RAIN HEAVY AT TIMES WILL CONTINUE SATURDAY...AND POSSIBLY INTO SATURDAY NIGHT...AND COULD PRODUCE ADDITIONAL FLOODING PROBLEMS ESPECIALLY ALONG SMALL STREAMS AND IN URBAN AREAS WITH POOR DRAINAGE. SCATTERED SHOWERS MAY LINGER SUNDAY AS WELL. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED.
The radar
The national radar mosaic for the moment the first event began.
Event by event
1 flood. Local standard time, as filed.
What these are
- Flood
- Flooding that develops more slowly than a flash flood: rivers leaving their banks, or water standing over land for an extended time.
After NWS Directive 10-1605, the rules offices file Storm Data by.
The same day elsewhere
- Tornadoes and Hail in Nebraska, June 20, 2003
- Flood in Pennsylvania, June 20 to 21, 2003
- Hail in Colorado, June 20, 2003
- Hail and Damaging Winds in Texas, June 20, 2003
- Damaging Winds in Texas, June 20, 2003
- Flash Flood in Florida, June 20, 2003
- Flash Flooding and Hail in Texas, June 20, 2003
- Flash Flood in Florida, June 20, 2003
- Damaging Wind in Montana, June 20, 2003
- Hail and Damaging Winds in South Dakota, June 20, 2003
- Tornado and Hail in Colorado, June 20, 2003
- Flash Flooding and Hail in Texas, June 20, 2003
More
Every storm in Pennsylvania in 2003Every state in 2003This day in weather historyWarnings in Pennsylvania, June 2003
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: 5376236.