Alert archive / New Jersey / Flash Flood Warnings in 2025
Flash Flood Warning 82, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 31, 2025, 2:30 PM EDT for Morris County, New Jersey. It was in force for 4 hr. 1 report 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
- Jul 31, 2025, 2:30 PM EDT (18:30 UTC)
- Expired
- Jul 31, 2025, 6:30 PM EDT
- In force
- 4 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Flood severity
- None
County Morris County, NJ
The radar
The Philadelphia radar (KDIX), 111 km from the middle of the area, began a volume at 18:31 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 |
|---|---|---|---|
| Jul 31, 3:55 PM EDT | FLASH FLOOD | Denville Twp, NJ | NJ DOT reports flooding on I-80 Westbound At West of Exit 38 - US 46 (Denville Twp), 1 left lane of 4 lanes closed. |
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, 6.5 hours before the alert went out and 135 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
- 1000 J/kg
- Mixed-layer CIN
- -70 J/kg
- Mixed-layer LCL
- 970 m above ground
- 0-6 km bulk shear
- 31 kt
- 0-1 km storm-relative helicity
- -13 m²/s²
- 0-3 km storm-relative helicity
- 82 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 0.4
The text
As transmitted.
894
WGUS51 KPHI 311830
FFWPHI
NJC027-312230-
/O.NEW.KPHI.FF.W.0082.250731T1830Z-250731T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
230 PM EDT Thu Jul 31 2025
The National Weather Service in Mount Holly has issued a
* Flash Flood Warning for...
Morris County in northern New Jersey...
* Until 630 PM EDT.
* At 230 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...
Morristown, Dover, Hopatcong, East Hanover, Lincoln Park,
Kinnelon, Boonton, Butler, Wharton, Rockaway, Morris Plains and
Mount Arlington.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
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 4103 7450 4105 7446 4104 7443 4102 7443
4100 7430 4098 7430 4097 7428 4093 7429
4090 7427 4091 7433 4087 7434 4086 7432
4080 7436 4075 7475 4090 7479 4092 7475
4090 7471 4092 7465 4096 7464 4107 7449
FLASH FLOOD...RADAR INDICATED
$$
MPS2 follow-up statements
396
WGUS71 KPHI 312107
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
507 PM EDT Thu Jul 31 2025
NJC027-312230-
/O.CON.KPHI.FF.W.0082.000000T0000Z-250731T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Morris NJ-
507 PM EDT Thu Jul 31 2025
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 630 PM EDT THIS
EVENING FOR MORRIS COUNTY...
At 507 PM EDT, Doppler radar indicated thunderstorms produced heavy
rain across the warned area. Between 1.5 and 2.5 inches of rain have
fallen. Additional rainfall amounts up to 0.5 inches are possible in
the warned area. Flash flooding is ongoing or expected to begin
shortly.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Radar.
IMPACT...Flooding of small creeks and streams, urban areas,
highways, streets, and underpasses as well as other
drainage and low lying areas.
Some locations that may experience flash flooding include...
Morristown, Dover, Hopatcong, East Hanover, Lincoln Park,
Kinnelon, Boonton, Butler, Wharton, Rockaway, Morris Plains and
Mount Arlington.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
Please report observed flooding to local emergency services or law
enforcement and request they pass this information to the National
Weather Service when you can do so safely.
&&
LAT...LON 4103 7450 4105 7446 4104 7443 4102 7443
4100 7430 4098 7430 4097 7428 4093 7429
4090 7427 4091 7433 4087 7434 4086 7432
4080 7436 4075 7475 4090 7479 4092 7475
4090 7471 4092 7465 4096 7464 4107 7449
FLASH FLOOD...RADAR INDICATED
$$
MPS381
WGUS71 KPHI 312222
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
622 PM EDT Thu Jul 31 2025
NJC027-312232-
/O.EXP.KPHI.FF.W.0082.000000T0000Z-250731T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Morris NJ-
622 PM EDT Thu Jul 31 2025
...FLASH FLOOD WARNING WILL EXPIRE AT 630 PM EDT THIS EVENING FOR
MORRIS COUNTY...
Although the heaviest rain has ended, continue to heed any road
closures that may be in effect due to earlier flooding.
A Flood Watch still remains in effect until 600 AM EDT Friday for
portions of northern Delaware, New Jersey, and southeast
Pennsylvania.
&&
LAT...LON 4103 7450 4105 7446 4104 7443 4102 7443
4100 7430 4098 7430 4097 7428 4093 7429
4090 7427 4091 7433 4087 7434 4086 7432
4080 7436 4075 7475 4090 7479 4092 7475
4090 7471 4092 7465 4096 7464 4107 7449
$$
MPSThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 31, 2:24 AM EDT | Small Craft Advisory | PHI | 70 hr | |
| Jul 31, 3:56 AM EDT | Rip Current Statement | PHI | Atlantic, Cape May, Monmouth, Ocean | 4 days |
| Jul 31, 1:27 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Middlesex, Morris, Somerset | 48 min |
| Jul 31, 1:48 PM EDT | Flash Flood Warning | PHI | Morris, Somerset | 4 hr |
| Jul 31, 1:49 PM EDT | Tornado Warning | PHI | Middlesex, Somerset | 26 min |
| Jul 31, 1:55 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Mercer | 18 min |
| Jul 31, 2:05 PM EDT | Severe Thunderstorm Warning | PHI | Gloucester, Salem | 40 min |
| Jul 31, 2:27 PM EDT | Flash Flood Warning | PHI | Camden, Gloucester | 4 hr |
| Jul 31, 2:38 PM EDT | Severe Thunderstorm Warning | PHI | Middlesex | 52 min |
| Jul 31, 2:46 PM EDT | Flash Flood Warning | PHI | Gloucester, Salem | 4 hr |
| Jul 31, 2:52 PM EDT | Flash Flood Warning | PHI | Middlesex | 4 hr |
| Jul 31, 2:55 PM EDT | Severe Thunderstorm Warning | PHI | Camden, Gloucester, Salem | 50 min |
| Jul 31, 2:57 PM EDT | Special Marine Warning | PHI | 63 min | |
| Jul 31, 3:03 PM EDT | Severe Thunderstorm Warning | PHI | Middlesex, Monmouth | 42 min |
| Jul 31, 3:10 PM EDT | Flash Flood Warning | PHI | Burlington, Camden, Gloucester, Mercer, Monmouth, Ocean | 4 hr |
| Jul 31, 3:10 PM EDT | Tornado Warning | PHI | Camden, Gloucester, Salem | 35 min |
| Jul 31, 3:12 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Ocean | 48 min |
| Jul 31, 3:49 PM EDT | Flash Flood Warning | PHI | Camden, Gloucester, Salem | 4 hr |
| Jul 31, 4:31 PM EDT | Flash Flood Warning | PHI | Middlesex, Monmouth | 3 hr |
| Jul 31, 4:36 PM EDT | Special Marine Warning | PHI | 54 min | |
| Jul 31, 4:39 PM EDT | Special Marine Warning | PHI | 36 min | |
| Jul 31, 4:43 PM EDT | Flash Flood Warning | PHI | Monmouth, Ocean | 4 hr |
| Jul 31, 5:21 PM EDT | Flash Flood Warning | PHI | Cumberland | 3 hr |
| Jul 31, 5:53 PM EDT | Flash Flood Warning | PHI | Atlantic, Burlington, Cape May, Ocean | 4 hr |
| Jul 31, 6:17 PM EDT | Special Marine Warning | PHI | 58 min | |
| Jul 31, 6:42 PM EDT | Special Marine Warning | PHI | 63 min | |
| Jul 31, 7:29 PM EDT | Special Marine Warning | PHI | 91 min |
Nearby
Flash Flood Warnings in New Jersey, 2025Every flash flood warning in 2025
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.