Alert archive / Pennsylvania / Flash Flood Warnings in 2024
Flash Flood Warning 61, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 18, 2024, 5:31 PM EDT for Hunterdon County, Warren County, New Jersey; Bucks County, Lehigh County, Northampton County, Pennsylvania. It was in force for 6 hr. 3 reports came from inside the area while it was in force.
The area
The outline as issued, with what was reported inside it.
The facts
- Issued
- Aug 18, 2024, 5:31 PM EDT (21:31 UTC)
- Expired
- Aug 18, 2024, 11:30 PM EDT
- In force
- 6 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Flood severity
- None
Counties Hunterdon County, NJ, Warren County, NJ, Bucks County, PA, Lehigh County, PA, Northampton County, PA
The radar
The Philadelphia radar (KDIX), 114 km from the middle of the area, began a volume at 21:34 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.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Aug 18, 8:32 PM EDT | FLOOD | 1 S Nazareth, PA | Intersection of S Broad St and Jandy Blvd closed due to flooding. Water rescues ongoing. |
| Aug 18, 8:32 PM EDT | FLASH FLOOD | 1 S Nazareth, PA | Corrects previous flood report from 1 S Nazareth. Intersection of S Broad St and Jandy Blvd closed due to flooding. Water rescues ongoing. |
| Aug 18, 10:32 PM EDT | FLASH FLOOD | 1 Sw North Catasauqua, PA | Water Street flooded at Eberhart Road near Coplay Creek. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Brookhaven, NY (KOKX), launched 12:00Z, 9.5 hours before the alert went out and 213 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.
- Mixed-layer CAPE
- 109 J/kg
- Mixed-layer CIN
- -20 J/kg
- Mixed-layer LCL
- 582 m above ground
- 0-6 km bulk shear
- 26 kt
- 0-1 km storm-relative helicity
- 187 m²/s²
- 0-3 km storm-relative helicity
- 205 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
The text
As transmitted.
211
WGUS51 KPHI 182131
FFWPHI
NJC019-041-PAC017-077-095-190130-
/O.NEW.KPHI.FF.W.0061.240818T2131Z-240819T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
531 PM EDT Sun Aug 18 2024
The National Weather Service in Mount Holly has issued a
* Flash Flood Warning for...
Western Hunterdon County in northwestern New Jersey...
Southwestern Warren County in northwestern New Jersey...
Southeastern Lehigh County in eastern Pennsylvania...
Southern Northampton County in eastern Pennsylvania...
Northwestern Bucks County in southeastern Pennsylvania...
* Until 930 PM EDT.
* At 531 PM EDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Between 1 and 2 inches of rain
have fallen. Additional rainfall amounts of 1 to 2 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, Easton, Bethlehem, Forks, Emmaus, Northampton, Wilson,
Hellertown, Nazareth, Bath, Alpha and Belfast.
This includes the following highways...
Interstate 78 in New Jersey between mile markers 0 and 5.
Northeast Extension between mile markers 43 and 62.
Interstate 78 in Pennsylvania between mile markers 52 and 76.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
Flooding is occurring or is imminent. It is important to know where
you are relative to streams, rivers, or creeks which can become
killers in heavy rains. Campers and hikers should avoid streams or
creeks.
Please report observed flooding to local emergency services or law
enforcement and request they pass this information to the National
Weather Service when you can do so safely.
&&
LAT...LON 4059 7561 4065 7561 4074 7545 4079 7534
4084 7531 4072 7525 4074 7512 4066 7511
4056 7517 4042 7542 4054 7555
FLASH FLOOD...RADAR INDICATED
$$
Hoeflich3 follow-up statements
013
WGUS71 KPHI 190046
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
846 PM EDT Sun Aug 18 2024
NJC019-041-PAC017-190056-
/O.CAN.KPHI.FF.W.0061.000000T0000Z-240819T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hunterdon NJ-Warren NJ-Bucks PA-
846 PM EDT Sun Aug 18 2024
...FLASH FLOOD WARNING IS CANCELLED FOR WESTERN HUNTERDON,
SOUTHWESTERN WARREN AND NORTHWESTERN BUCKS COUNTIES...
Flooding is no longer expected to pose a threat. Please continue to
heed remaining road closures.
A Flood Watch remains in effect until 200 AM EDT for portions of
northern Delaware, New Jersey, and Pennsylvania.
&&
LAT...LON 4079 7534 4084 7531 4072 7525 4073 7518
4070 7520 4068 7520 4067 7520 4067 7521
4067 7523 4064 7525 4062 7528 4059 7532
4049 7548 4059 7561 4065 7561 4074 7545
$$
PAC077-095-190130-
/O.CON.KPHI.FF.W.0061.000000T0000Z-240819T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Lehigh PA-Northampton PA-
846 PM EDT Sun Aug 18 2024
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 930 PM EDT THIS
EVENING FOR SOUTHEASTERN LEHIGH AND SOUTHWESTERN NORTHAMPTON
COUNTIES...
At 846 PM EDT, Doppler radar indicated thunderstorms producing heavy
rain across the warned area. Between 1.5 and 2.5 inches of rain have
fallen. Additional rainfall amounts of 1 to 2 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, Easton, Bethlehem, Forks, Emmaus, Northampton, Wilson,
Hellertown, Nazareth, Bath, Belfast and West Easton.
This includes the following highways...
Northeast Extension near mile marker 49...and
between mile markers 51 and 62.
Interstate 78 in Pennsylvania between mile markers 52 and 76.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
Be especially cautious at night when it is harder to recognize the
dangers of flooding.
Please report observed flooding to local emergency services or law
enforcement and request they pass this information to the National
Weather Service when you can do so safely.
&&
LAT...LON 4079 7534 4084 7531 4072 7525 4073 7518
4070 7520 4068 7520 4067 7520 4067 7521
4067 7523 4064 7525 4062 7528 4059 7532
4049 7548 4059 7561 4065 7561 4074 7545
FLASH FLOOD...RADAR INDICATED
$$
Hoeflich491
WGUS51 KPHI 190111
FFWPHI
PAC077-095-190330-
/O.EXT.KPHI.FF.W.0061.000000T0000Z-240819T0330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
911 PM EDT Sun Aug 18 2024
The National Weather Service in Mount Holly has extended the
* Flash Flood Warning for...
Southeastern Lehigh County in eastern Pennsylvania...
Southwestern Northampton County in eastern Pennsylvania...
* Until 1130 PM EDT.
* At 911 PM EDT, emergency management reported thunderstorms
producing heavy rain with water rescues around Nazareth and
several roads reported closed in that area. Another round of
showers and thunderstorms are moving in. Between 3 and 4 inches of
rain have fallen. Additional rainfall amounts of 1 to 2 inches are
possible in the warned area. Flash flooding is already occurring.
HAZARD...Life threatening flash flooding caused by
thunderstorms.
SOURCE...Emergency management reported.
IMPACT...Life threatening flash flooding of creeks and streams,
urban areas, highways, streets, and underpasses.
* Some locations that may experience flash flooding include...
Allentown, Easton, Bethlehem, Forks, Emmaus, Northampton, Wilson,
Hellertown, Nazareth, Bath, Belfast and West Easton.
This includes the following highways...
Northeast Extension near mile marker 49...and
between mile markers 51 and 62.
Interstate 78 in Pennsylvania between mile markers 52 and 74.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
Be especially cautious at night when it is harder to recognize the
dangers of flooding.
Please report observed flooding to local emergency services or law
enforcement and request they pass this information to the National
Weather Service when you can do so safely.
&&
LAT...LON 4079 7534 4084 7531 4072 7525 4073 7518
4070 7520 4068 7520 4067 7520 4067 7521
4067 7523 4064 7525 4062 7528 4059 7532
4049 7548 4059 7561 4065 7561 4074 7545
FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
Hoeflich654
WGUS71 KPHI 190320
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
1120 PM EDT Sun Aug 18 2024
PAC077-095-190330-
/O.EXP.KPHI.FF.W.0061.000000T0000Z-240819T0330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Lehigh PA-Northampton PA-
1120 PM EDT Sun Aug 18 2024
...FLASH FLOOD WARNING WILL EXPIRE AT 1130 PM EDT THIS EVENING FOR
SOUTHEASTERN LEHIGH AND SOUTHWESTERN NORTHAMPTON COUNTIES...
The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed remaining road closures.
A Flood Watch remains in effect until 200 AM EDT for portions of
northern Delaware, New Jersey, and Pennsylvania.
&&
LAT...LON 4079 7534 4084 7531 4072 7525 4073 7518
4070 7520 4068 7520 4067 7520 4067 7521
4067 7523 4064 7525 4062 7528 4059 7532
4049 7548 4059 7561 4065 7561 4074 7545
$$
HoeflichThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 18, 3:09 AM EDT | Flash Flood Warning | PHI | Burlington, Camden | 93 min |
| Aug 18, 4:41 AM EDT | Flash Flood Warning | PHI | Burlington, Camden, Mercer | 2 hr |
| Aug 18, 2:17 PM EDT | Special Marine Warning | PHI | 58 min | |
| Aug 18, 2:42 PM EDT | Special Marine Warning | PHI | 93 min | |
| Aug 18, 3:55 PM EDT | Special Marine Warning | PHI | 95 min | |
| Aug 18, 4:04 PM EDT | Severe Thunderstorm Warning | PHI | Warren | 41 min |
| Aug 18, 4:41 PM EDT | Severe Thunderstorm Warning | PHI | Sussex, Warren | 34 min |
| Aug 18, 4:56 PM EDT | Flash Flood Warning | PHI | Warren | 6 hr |
| Aug 18, 5:10 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Morris, Warren | 29 min |
| Aug 18, 5:21 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Camden | 39 min |
| Aug 18, 5:38 PM EDT | Flash Flood Warning | PHI | Sussex, Warren | 4 hr |
| Aug 18, 5:47 PM EDT | Severe Thunderstorm Warning | PHI | Morris, Sussex | 43 min |
| Aug 18, 5:47 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Mercer, Middlesex, Monmouth | 58 min |
| Aug 18, 5:51 PM EDT | Severe Thunderstorm Warning | PHI | Morris, Somerset | 24 min |
| Aug 18, 5:59 PM EDT | Severe Thunderstorm Warning | PHI | Morris, Sussex | 18 min |
| Aug 18, 6:01 PM EDT | Flash Flood Warning | PHI | Hunterdon, Morris, Somerset, Sussex, Warren | 6 hr |
| Aug 18, 6:24 PM EDT | Severe Thunderstorm Warning | PHI | Middlesex, Morris, Somerset | 66 min |
| Aug 18, 6:36 PM EDT | Flash Flood Warning | PHI | Morris, Somerset | 5 hr |
| Aug 18, 1:35 AM EDT | Flash Flood Warning | PHI | Bucks, Delaware, Montgomery, Philadelphia | 2 hr |
| Aug 18, 3:24 PM EDT | Severe Thunderstorm Warning | PHI | Monroe, Northampton | 19 min |
| Aug 18, 3:34 PM EDT | Severe Thunderstorm Warning | PHI | Chester, Delaware, Montgomery, Philadelphia | 41 min |
| Aug 18, 3:48 PM EDT | Severe Thunderstorm Warning | PHI | Carbon, Monroe | 42 min |
| Aug 18, 4:25 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Lehigh, Montgomery, Northampton | 28 min |
Nearby
Flash Flood Warnings in Pennsylvania, 2024Flash Flood Warnings in New Jersey, 2024Every flash flood warning in 2024
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.