Alert archive / New Jersey / Flash Flood Warnings in 2026
Flash Flood Warning 88, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 3, 2026, 2:50 AM EDT for 4 counties in New Jersey. It was in force for 4 hr. 5 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 3, 2026, 2:50 AM EDT (06:50 UTC)
- Expired
- Aug 3, 2026, 7:15 AM EDT
- In force
- 4 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Flood severity
- None
Counties Hunterdon County, NJ, Mercer County, NJ, Morris County, NJ, Somerset County, NJ
The radar
The Philadelphia radar (KDIX), 85 km from the middle of the area, began a volume at 06:53 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 3, 3:00 AM EDT | FLASH FLOOD | 1 Ese Somerville, NJ | Veterans Memorial Drive was impassable due to flood water. Time from report. |
| Aug 3, 3:19 AM EDT | FLOOD | 2 Ne Boonton Twp, NJ | Report from mPING: River/Creek overflowing; Cropland/Yard/Basement Flooding. |
| Aug 3, 4:43 AM EDT | FLASH FLOOD | Morris Twp, NJ | Woodland Ave was closed due to flooding. The road has since reopened. Time from report. |
| Aug 3, 4:44 AM EDT | FLASH FLOOD | Dover, NJ | Union Street flooded in Dover. Time from report. |
| Aug 3, 6:00 AM EDT | RAIN 1.42 | Readington Twp, NJ | overnight total. |
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 00:00Z, 6.8 hours before the alert went out and 141 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
- 151 J/kg
- Mixed-layer CIN
- -2 J/kg
- Mixed-layer LCL
- 507 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km storm-relative helicity
- 163 m²/s²
- 0-3 km storm-relative helicity
- 198 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 1.7
The text
As transmitted.
466
WGUS51 KPHI 030650
FFWPHI
NJC019-021-027-035-030945-
/O.NEW.KPHI.FF.W.0088.260803T0650Z-260803T0945Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
250 AM EDT Mon Aug 3 2026
The National Weather Service in Mount Holly has issued a
* Flash Flood Warning for...
Northwestern Mercer County in central New Jersey...
Morris County in northern New Jersey...
Somerset County in northern New Jersey...
Southeastern Hunterdon County in northwestern New Jersey...
* Until 545 AM EDT.
* At 250 AM EDT, Doppler radar and automated rain gauges indicated
thunderstorms producing heavy rain across the warned area. Between
0.5 and 1.5 inches of rain have fallen. The expected rainfall rate
is 1 to 2 inches in 1 hour. 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 and automated gauges.
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, Somerville, Bridgewater, Dover, Madison, Middlesex,
Florham Park, East Hanover, Lincoln Park, Bound Brook, Manville
and Kinnelon.
This includes the following highways...
Interstate 287 in New Jersey between mile markers 12 and 53.
Interstate 78 in New Jersey between mile markers 21 and 42.
Interstate 80 in New Jersey between mile markers 33 and 48.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
&&
LAT...LON 4041 7504 4105 7446 4104 7443 4102 7443
4100 7430 4097 7428 4090 7427 4091 7433
4086 7432 4076 7438 4075 7436 4067 7446
4066 7445 4067 7440 4064 7442 4058 7451
4055 7452 4028 7486 4034 7494 4040 7497
FLASH FLOOD...RADAR AND GAUGE INDICATED
EXPECTED RAINFALL RATE...1-2 INCHES IN 1 HOUR
$$
Cooper3 follow-up statements
521
WGUS71 KPHI 030819
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
419 AM EDT Mon Aug 3 2026
NJC019-021-027-035-030945-
/O.CON.KPHI.FF.W.0088.000000T0000Z-260803T0945Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hunterdon NJ-Mercer NJ-Morris NJ-Somerset NJ-
419 AM EDT Mon Aug 3 2026
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 545 AM EDT EARLY THIS
MORNING FOR NORTHWESTERN MERCER, MORRIS, SOMERSET AND SOUTHEASTERN
HUNTERDON COUNTIES...
At 419 AM EDT, Doppler radar and automated rain gauges indicated
thunderstorms producing heavy rain across the warned area. Between
1.5 and 3 inches of rain have fallen. The expected rainfall rate is
1 to 2 inches in 1 hour. Additional rainfall amounts of 1 to 2
inches are possible in the warned area. Flash flooding is ongoing or
expected to begin shortly.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Radar and automated gauges.
IMPACT...Flooding of small creeks and streams, urban areas,
highways, streets, and underpasses as well as other
drainage and low lying areas.
Some locations that may experience flash flooding include...
Morristown, Somerville, Bridgewater, Dover, Madison, Middlesex,
Florham Park, East Hanover, Lincoln Park, Bound Brook, Manville
and Kinnelon.
This includes the following highways...
Interstate 287 in New Jersey between mile markers 12 and 53.
Interstate 78 in New Jersey between mile markers 22 and 42.
Interstate 80 in New Jersey between mile markers 34 and 48.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
&&
LAT...LON 4041 7504 4105 7446 4104 7443 4102 7443
4100 7430 4097 7428 4090 7427 4091 7433
4086 7432 4076 7438 4075 7436 4067 7446
4066 7445 4067 7440 4064 7442 4058 7451
4055 7452 4028 7486 4034 7494 4040 7497
FLASH FLOOD...RADAR AND GAUGE INDICATED
EXPECTED RAINFALL RATE...1-2 INCHES IN 1 HOUR
$$
Cooper971
WGUS51 KPHI 030937
FFWPHI
NJC019-021-027-035-031115-
/O.EXT.KPHI.FF.W.0088.000000T0000Z-260803T1115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
537 AM EDT Mon Aug 3 2026
The National Weather Service in Mount Holly has extended the
* Flash Flood Warning for...
Northwestern Mercer County in central New Jersey...
Morris County in northern New Jersey...
Somerset County in northern New Jersey...
Southeastern Hunterdon County in northwestern New Jersey...
* Until 715 AM EDT.
* At 537 AM EDT, Doppler radar and automated rain gauges indicated
thunderstorms producing heavy rain across portions of the warned
area. Gages on the Whippany River at Morristown and the Neshanic
River at Reaville have both shown rapid rates of rise to near
flood stage. Between 1.5 and 3 inches of rain have fallen across
the warned area with an additional rainfall amount up to 1 inch
are possible in the warned area. Flash flooding is ongoing or
expected to begin shortly.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Radar and automated gauges.
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, Somerville, Bridgewater, Dover, Madison, Middlesex,
Florham Park, East Hanover, Lincoln Park, Bound Brook, Manville
and Kinnelon.
This includes the following highways...
Interstate 287 in New Jersey between mile markers 12 and 53.
Interstate 78 in New Jersey between mile markers 22 and 42.
Interstate 80 in New Jersey between mile markers 34 and 48.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
&&
LAT...LON 4041 7504 4105 7446 4104 7443 4102 7443
4100 7430 4097 7428 4090 7427 4091 7433
4086 7432 4076 7438 4075 7436 4067 7446
4066 7445 4067 7440 4064 7442 4058 7451
4055 7452 4028 7486 4034 7494 4040 7497
FLASH FLOOD...RADAR AND GAUGE INDICATED
$$
Deal657
WGUS71 KPHI 031107
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
707 AM EDT Mon Aug 3 2026
NJC019-021-027-035-031117-
/O.EXP.KPHI.FF.W.0088.000000T0000Z-260803T1115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hunterdon NJ-Mercer NJ-Morris NJ-Somerset NJ-
707 AM EDT Mon Aug 3 2026
...FLASH FLOOD WARNING WILL EXPIRE AT 715 AM EDT THIS MORNING FOR
NORTHWESTERN MERCER, MORRIS, SOMERSET AND SOUTHEASTERN HUNTERDON
COUNTIES...
Water levels on faster responding rivers and creeks in the warned
area have crested and are receding. The heavy rain has ended.
Flooding is no longer expected to pose a threat. Please continue to
heed remaining road closures.
A Flood Watch remains in effect until 1100 PM EDT Monday for
portions of northern Delaware, New Jersey, and Pennsylvania.
&&
LAT...LON 4041 7504 4105 7446 4104 7443 4102 7443
4100 7430 4097 7428 4090 7427 4091 7433
4086 7432 4076 7438 4075 7436 4067 7446
4066 7445 4067 7440 4064 7442 4058 7451
4055 7452 4028 7486 4034 7494 4040 7497
$$
DealThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 2, 11:20 PM EDT | Flash Flood Warning | PHI | Warren | 4 hr |
| Aug 3, 12:05 AM EDT | Flash Flood Warning | PHI | Hunterdon, Warren | 3 hr |
| Aug 3, 12:36 AM EDT | Special Marine Warning | PHI | 84 min | |
| Aug 3, 3:05 AM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Mercer, Somerset | 40 min |
| Aug 3, 4:41 AM EDT | Flash Flood Warning | PHI | Burlington, Camden, Gloucester, Mercer, Middlesex, Somerset | 2 hr |
| Aug 3, 5:59 AM EDT | Flash Flood Warning | PHI | Middlesex, Somerset | 4 hr |
| Aug 3, 7:02 AM EDT | Areal Flood Warning | PHI | Burlington, Camden, Gloucester, Mercer, Middlesex, Somerset | 3 hr |
| Aug 3, 8:21 AM EDT | Special Marine Warning | PHI | 69 min | |
| Aug 3, 9:08 AM EDT | Flash Flood Warning | PHI | Burlington, Camden, Gloucester, Mercer, Salem | 3 hr |
| Aug 3, 10:12 AM EDT | Flash Flood Warning | PHI | Atlantic, Cumberland, Salem | 86 min |
| Aug 3, 10:36 AM EDT | Flash Flood Warning | PHI | Burlington, Mercer, Middlesex, Monmouth, Ocean, Somerset | 6 hr |
| Aug 3, 10:44 AM EDT | Flash Flood Warning | PHI | Burlington, Camden, Gloucester | 6 hr |
| Aug 3, 12:01 PM EDT | Areal Flood Warning | PHI | Mercer | 74 min |
| Aug 3, 1:20 PM EDT | Areal Flood Warning | PHI | Burlington, Camden, Mercer | 4 hr |
| Aug 3, 1:51 PM EDT | Special Marine Warning | PHI | 24 min | |
| Aug 3, 2:53 PM EDT | Special Marine Warning | PHI | 97 min | |
| Aug 3, 2:57 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Ocean | 27 min |
| Aug 3, 5:15 PM EDT | Special Marine Warning | PHI | 90 min |
Nearby
Flash Flood Warnings in New Jersey, 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.