Alert archive / Pennsylvania / Flash Flood Warnings in 2026

Flash Flood Warning 71, NWS Philadelphia/Mount Holly

July 28, 2026Lehigh County, Monroe County, Northampton County, Pennsylvania

NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 28, 2026, 1:02 PM EDT for Lehigh County, Monroe County, Northampton County, Pennsylvania. It was in force for 4 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 28, 2026, 1:02 PM EDT (17:02 UTC)
Expired
Jul 28, 2026, 5:00 PM EDT
In force
4 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

Counties Lehigh County, PA, Monroe County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 118 km from the middle of the area, began a volume at 17:03 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 5.0 hours before the alert went out and 207 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Brookhaven, NY at 12:00Z on 2026-07-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1266 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 12:00Z on 2026-07-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 41 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
1266 J/kg
Mixed-layer CIN
-16 J/kg
Mixed-layer LCL
637 m above ground
0-6 km bulk shear
12 kt
0-1 km storm-relative helicity
41 m²/s²
0-3 km storm-relative helicity
63 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

333 
WGUS51 KPHI 281702
FFWPHI
PAC077-089-095-282100-
/O.NEW.KPHI.FF.W.0071.260728T1702Z-260728T2100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
102 PM EDT Tue Jul 28 2026

The National Weather Service in Mount Holly has issued a

* Flash Flood Warning for...
  Central Lehigh County in eastern Pennsylvania...
  Northampton County in eastern Pennsylvania...
  South Central Monroe County in northeastern Pennsylvania...

* Until 500 PM EDT.

* At 102 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across portions of the warned area. Between 0.5 and 1.5 
  inches of rain have fallen. The expected rainfall rate is 1.5 to 
  2.5 inches in 1 hour. Additional rainfall amounts of 0.5 to 1.5 
  inches are possible in the warned area. Flash flooding is ongoing 
  or expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flooding of small creeks and streams, urban areas,
           highways, streets, and underpasses as well as other
           drainage and low lying areas.

* Some locations that may experience flash flooding include...
  Allentown, Bethlehem, Emmaus, Northampton, Nazareth, Bangor, Pen 
  Argyl, Wind Gap, Bath, Belfast, Tatamy and East Bangor.

This includes the following highways...
	Northeast Extension between mile markers 49 and 63.
	Interstate 78 in Pennsylvania between mile markers 47 and 66.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around...don't drown when encountering flooded roads. Most 
flood deaths occur in vehicles.

&&

LAT...LON 4087 7507 4046 7551 4059 7572 4095 7521

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL RATE...1.5-2.5 INCHES IN 1 HOUR

$$

Kruzdlo
2 follow-up statements
568 
WGUS71 KPHI 281857
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
257 PM EDT Tue Jul 28 2026

PAC077-281907-
/O.CAN.KPHI.FF.W.0071.000000T0000Z-260728T2100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Lehigh PA-
257 PM EDT Tue Jul 28 2026

...FLASH FLOOD WARNING IS CANCELLED FOR CENTRAL LEHIGH COUNTY...

At this time, flooding is no longer expected to pose a threat.

A Flood Watch remains in effect until 800 PM EDT Wednesday for 
portions of New Jersey and Pennsylvania.

&&

LAT...LON 4087 7507 4057 7539 4058 7540 4060 7539
      4061 7539 4062 7538 4063 7539 4067 7543
      4066 7548 4067 7549 4070 7551 4072 7553
      4073 7553 4095 7521

$$

PAC089-095-282100-
/O.CON.KPHI.FF.W.0071.000000T0000Z-260728T2100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Monroe PA-Northampton PA-
257 PM EDT Tue Jul 28 2026

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 5 PM EDT THIS 
AFTERNOON FOR NORTHAMPTON AND SOUTH CENTRAL MONROE COUNTIES...

At 257 PM EDT, Doppler radar indicated thunderstorms produced up to 
2.50 inches of rain across portions of the warned area. The rain 
fell in short period of time with the heaviest rain falling between 
Wind Gap and Pen Argyl.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar.

IMPACT...Flooding of small creeks and streams, urban areas,
         highways, streets, and underpasses as well as other
         drainage and low lying areas.

Some locations that may experience flash flooding include...
  Bethlehem, Northampton, Nazareth, Bangor, Pen Argyl, Wind Gap, 
  Bath, Belfast, Tatamy, East Bangor, Steuben and Beersville.

This includes Interstate 78 in Pennsylvania near mile marker 65.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around...don't drown when encountering flooded roads. Most 
flood deaths occur in vehicles.

&&

LAT...LON 4087 7507 4057 7539 4058 7540 4060 7539
      4061 7539 4062 7538 4063 7539 4067 7543
      4066 7548 4067 7549 4070 7551 4072 7553
      4073 7553 4095 7521

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL RATE...1.5-2.5 INCHES IN 1 HOUR

$$

Kruzdlo
501 
WGUS71 KPHI 282053
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
453 PM EDT Tue Jul 28 2026

PAC089-095-282103-
/O.EXP.KPHI.FF.W.0071.000000T0000Z-260728T2100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Monroe PA-Northampton PA-
453 PM EDT Tue Jul 28 2026

...FLASH FLOOD WARNING WILL EXPIRE AT 5 PM EDT THIS AFTERNOON FOR 
NORTHAMPTON AND SOUTH CENTRAL MONROE COUNTIES...

Flood waters have receded. Please continue to heed any remaining 
road closures.

A Flood Watch remains in effect until 800 PM EDT Wednesday for 
portions of New Jersey and Pennsylvania as additional rainfall is 
expected.

&&

LAT...LON 4087 7507 4057 7539 4058 7540 4060 7539
      4061 7539 4062 7538 4063 7539 4067 7543
      4066 7548 4067 7549 4070 7551 4072 7553
      4073 7553 4095 7521

$$

AKL

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 27, 8:01 PM EDTSevere Thunderstorm WarningPHIChester23 min
Jul 28, 1:22 PM EDTSevere Thunderstorm WarningPHILehigh, Northampton38 min
Jul 28, 1:31 PM EDTSevere Thunderstorm WarningPHINorthampton44 min
Jul 28, 1:49 PM EDTTornado WarningPHIMonroe, Northampton26 min
Jul 28, 2:15 PM EDTSevere Thunderstorm WarningPHINorthampton45 min
Jul 28, 5:08 PM EDTSevere Thunderstorm WarningPHILehigh, Northampton15 min
Jul 28, 5:22 PM EDTSevere Thunderstorm WarningPHIBucks34 min
Jul 28, 5:29 PM EDTSevere Thunderstorm WarningPHIChester61 min
Jul 28, 5:47 PM EDTSevere Thunderstorm WarningPHIBucks, Northampton43 min
Jul 28, 5:55 PM EDTFlash Flood WarningPHIBerks3 hr
Jul 28, 6:16 PM EDTTornado WarningPHIChester29 min
Jul 28, 6:17 PM EDTFlash Flood WarningPHIBucks, Lehigh, Northampton6 hr
Jul 28, 6:23 PM EDTSevere Thunderstorm WarningPHIChester, Delaware67 min
Jul 28, 6:46 PM EDTTornado WarningPHIDelaware29 min
Jul 28, 6:56 PM EDTFlash Flood WarningPHIBucks, Lehigh, Northampton5 hr
Jul 28, 7:06 PM EDTSevere Thunderstorm WarningPHIChester, Delaware, Montgomery, Philadelphia54 min
Jul 28, 7:08 PM EDTSevere Thunderstorm WarningPHIBerks, Chester, Montgomery35 min
Jul 28, 7:11 PM EDTFlash Flood WarningPHIDelaware, Philadelphia3 hr
Jul 28, 7:24 PM EDTFlash Flood WarningPHIChester4 hr
Jul 28, 7:31 PM EDTSevere Thunderstorm WarningPHIBucks, Northampton44 min
Jul 28, 7:55 PM EDTFlash Flood WarningPHIBucks, Montgomery4 hr

Nearby

Flash Flood Warnings in Pennsylvania, 2026Every flash flood warning in 2026

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.