Alert archive / New Jersey / Flash Flood Warnings in 2023

Flash Flood Warning 13, NWS Philadelphia/Mount Holly

June 26, 20234 counties in New Jersey

NWS Philadelphia/Mount Holly issued this flash flood warning at Jun 26, 2023, 5:55 PM EDT for 4 counties in New Jersey. It was in force for 6 hr. 31 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
Jun 26, 2023, 5:55 PM EDT (21:55 UTC)
Expired
Jun 27, 2023, 12:00 AM EDT
In force
6 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

Counties Hunterdon County, NJ, Morris County, NJ, Somerset County, NJ, Sussex County, NJ

The radar

The Philadelphia radar (KDIX), 105 km from the middle of the area, began a volume at 21:57 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

TimeReportWhereRemark
Jun 26, 6:04 PM EDTFLOOD1 Nnw Randolph, NJFlooding on NJ 10 westbound CR 670 (Randolph Twp) 2 Right lanes of 3 lanes closed. Time given in report.
Jun 26, 6:04 PM EDTFLOOD1 Nnw Randolph, NJFlooding on NJ 10 westbound CR 670 (Randolph Twp) 2 Right lanes of 3 lanes closed. Time given in report.
Jun 26, 6:09 PM EDTFLOODRaritan, NJFlooding on NJ 10 eastbound In the vicinity of US 202 (Morris Plains) 2 Right lanes of 3 lanes closed. Time given in report.
Jun 26, 6:09 PM EDTFLOODRaritan, NJFlooding on NJ 10 eastbound In the vicinity of US 202 (Morris Plains) 2 Right lanes of 3 lanes closed. Time given in report.
Jun 26, 6:13 PM EDTFLOODDover, NJFlooding on US 46 both directions East of NJ 15 (Dover). Time given in report.
Jun 26, 6:13 PM EDTFLOODDover, NJFlooding on US 46 both directions East of NJ 15 (Dover). Time given in report.
Jun 26, 6:30 PM EDTFLASH FLOOD1 Se Dover, NJReport of vehicles stranded on Route 10 in Morris County, NJ. Time given in report.
Jun 26, 6:30 PM EDTFLASH FLOOD1 Se Dover, NJReport of vehicles stranded on Route 10 in Morris County, NJ. Time given in report.
Jun 26, 6:45 PM EDTRAIN 21 N Pleasant Plains, NJMesonet station BKRN4 1.3 N Pleasant Plains.
Jun 26, 6:45 PM EDTRAIN 2.321 Nnw Ironia, NJMesonet station IRON4 Ironia.
Jun 26, 7:15 PM EDTRAIN 3.282 Wnw Morris Plains, NJMesonet station MSPN4 2.2 SW Denville.
Jun 26, 7:25 PM EDTFLASH FLOOD1 Ne Morristown, NJThe Whippany River gauge at Morristown reached minor flood stage of 6.01 feet.
Jun 26, 7:25 PM EDTFLASH FLOOD1 Ne Morristown, NJThe Whippany River gauge at Morristown reached minor flood stage of 6.01 feet.
Jun 26, 7:30 PM EDTRAIN 2.952 Se Pottersville, NJMesonet station POTN4 1.8 SE Pottersville.
Jun 26, 7:31 PM EDTFLOOD1 Ssw Landing, NJFlooding on I-80 eastbound Exit 28 - CR 631/US 46 (Roxbury Twp) 1 Left lane of 3 lanes closed. Time given in report.
Jun 26, 7:31 PM EDTFLOOD1 Ssw Landing, NJFlooding on I-80 eastbound Exit 28 - CR 631/US 46 (Roxbury Twp) 1 Left lane of 3 lanes closed. Time given in report.
Jun 26, 7:40 PM EDTRAIN 2.061 E Succasunna, NJMesonet station CW1735 Succasunna.
Jun 26, 7:44 PM EDTRAIN 4.811 Ese Ironia, NJMesonet station EW6513 Randolph.
Jun 26, 7:45 PM EDTRAIN 2.471 Ne Landing, NJMesonet station EW4706 Succasunna.
Jun 26, 7:45 PM EDTRAIN 3.073 Ne Lebanon, NJMesonet station CW5367 Hackettstown.
Jun 26, 7:46 PM EDTRAIN 3.55Boonton Twp, NJMesonet station AV873 Boonton.
Jun 26, 7:47 PM EDTRAIN 2.61Morris Plains, NJMesonet station FW7545 Morris Plains.
Jun 26, 7:47 PM EDTRAIN 4.111 Sw Mountain Lakes, NJMesonet station DW1105 Denville.
Jun 26, 7:48 PM EDTRAIN 2.521 Sw Towaco, NJMesonet station FW2458 Montville.
Jun 26, 7:49 PM EDTRAIN 2.122 Nne Califon, NJMesonet station DW2180 Califon.
Jun 26, 7:49 PM EDTRAIN 2.31 Sw Hopatcong, NJMesonet station HOPTA 1 SW Hopatcong.
Jun 26, 7:49 PM EDTRAIN 2.91 Sse Long Valley, NJMesonet station LNOFL Long Valley.
Jun 26, 8:06 PM EDTRAIN 4.3Parsippany, NJReport of 4.3 inches of rain since 4 PM. Time given in observation.
Jun 26, 8:09 PM EDTFLOOD2 E Lebanon, NJFlooding on US 22 westbound East of Potterstown Rd (Readington Twp) All lanes closed. Time given in report.
Jun 26, 8:09 PM EDTFLOOD2 E Lebanon, NJFlooding on US 22 westbound East of Potterstown Rd (Readington Twp) All lanes closed. Time given in report.
Jun 26, 8:30 PM EDTRAIN 3.04Pompton Plains, NJReport sent in via social media.

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, 9.9 hours before the alert went out and 136 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 2023-06-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 369 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 2023-06-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 57 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
369 J/kg
Mixed-layer CIN
-76 J/kg
Mixed-layer LCL
807 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
57 m²/s²
0-3 km storm-relative helicity
81 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.1

Open this sounding in Storm Lab

The text

As transmitted.

652 
WGUS51 KPHI 262155
FFWPHI
NJC019-027-035-037-270200-
/O.NEW.KPHI.FF.W.0013.230626T2155Z-230627T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
555 PM EDT Mon Jun 26 2023

The National Weather Service in Mount Holly has issued a

* Flash Flood Warning for...
  Morris County in northern New Jersey...
  Northern Somerset County in northern New Jersey...
  Northeastern Hunterdon County in northwestern New Jersey...
  Southeastern Sussex County in northwestern New Jersey...

* Until 1000 PM EDT.

* At 555 PM EDT, Doppler radar and automated rain gauges indicated 
  thunderstorms producing heavy rain across the warned area. Between 
  1 and 3 inches of rain have fallen. The expected rainfall rate is 
  0.5 to 1 inch 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 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, Hopatcong, 
  Florham Park, East Hanover, Lincoln Park, Manville, Kinnelon, and 
  Chatham.

This includes the following highways...
	Interstate 78 in New Jersey between mile markers 19 and 41.
	Interstate 80 in New Jersey between mile markers 27 and 48.
	Interstate 287 in New Jersey between mile markers 14 and 53.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4091 7468 4099 7465 4110 7451 4110 7449
      4103 7450 4105 7445 4102 7443 4100 7430
      4097 7428 4093 7429 4091 7427 4091 7433
      4087 7434 4086 7432 4079 7437 4074 7437
      4069 7445 4055 7459 4060 7486 4076 7489

FLASH FLOOD...RADAR AND GAUGE INDICATED
EXPECTED RAINFALL RATE...0.5-1 INCH IN 1 HOUR

$$

Staarmann
4 follow-up statements
495 
WGUS71 KPHI 262234
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
634 PM EDT Mon Jun 26 2023

NJC019-027-035-037-270200-
/O.CON.KPHI.FF.W.0013.000000T0000Z-230627T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hunterdon NJ-Morris NJ-Somerset NJ-Sussex NJ-
634 PM EDT Mon Jun 26 2023

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 10 PM EDT THIS 
EVENING FOR MORRIS, NORTHERN SOMERSET, NORTHEASTERN HUNTERDON, AND 
SOUTHEASTERN SUSSEX COUNTIES...

At 634 PM EDT, local law enforcement reported thunderstorms 
producing heavy rain across the warned area. Between 1.5 and 3 
inches of rain have fallen. The expected rainfall rate is 0.5 to 1 
inch in 1 hour. Additional rainfall amounts of 0.5 to 1.5 inches are 
possible in the warned area. Flash flooding is already occurring.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Law enforcement reported.

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, Hopatcong, 
  Florham Park, East Hanover, Lincoln Park, Manville, Kinnelon, and 
  Chatham.

This includes the following highways...
	Interstate 78 in New Jersey between mile markers 19 and 38.
	Interstate 80 in New Jersey between mile markers 27 and 48.
	Interstate 287 in New Jersey between mile markers 15 and 53.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

In hilly terrain there are hundreds of low water crossings which are 
potentially dangerous in heavy rain. Do not attempt to cross flooded 
roads. Find an alternate route.

&&

LAT...LON 4091 7468 4099 7465 4110 7451 4110 7449
      4103 7450 4105 7445 4102 7443 4100 7430
      4097 7428 4093 7429 4091 7427 4091 7433
      4087 7434 4086 7432 4079 7437 4074 7437
      4069 7445 4055 7459 4060 7486 4076 7489

FLASH FLOOD...OBSERVED
EXPECTED RAINFALL RATE...0.5-1 INCH IN 1 HOUR

$$

Staarmann
814 
WGUS71 KPHI 262350
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
750 PM EDT Mon Jun 26 2023

NJC019-027-035-037-270200-
/O.CON.KPHI.FF.W.0013.000000T0000Z-230627T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hunterdon NJ-Morris NJ-Somerset NJ-Sussex NJ-
750 PM EDT Mon Jun 26 2023

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 10 PM EDT THIS 
EVENING FOR MORRIS, NORTHERN SOMERSET, NORTHEASTERN HUNTERDON, AND 
SOUTHEASTERN SUSSEX COUNTIES...

At 750 PM EDT, local law enforcement reported thunderstorms 
producing heavy rain across the warned area. Between 2 and 4 inches 
of rain have fallen. The expected rainfall rate is 0.25 to 0.5 
inches in 1 hour. Additional rainfall amounts up to 0.5 inches are 
possible in the warned area. Flash flooding is already occurring.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Law enforcement reported.

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, Hopatcong, 
  Florham Park, East Hanover, Lincoln Park, Manville, Kinnelon, and 
  Chatham.

This includes the following highways...
	Interstate 78 in New Jersey between mile markers 19 and 38.
	Interstate 80 in New Jersey between mile markers 27 and 48.
	Interstate 287 in New Jersey between mile markers 15 and 53.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4091 7468 4099 7465 4110 7451 4110 7449
      4103 7450 4105 7445 4102 7443 4100 7430
      4097 7428 4093 7429 4091 7427 4091 7433
      4087 7434 4086 7432 4079 7437 4074 7437
      4069 7445 4055 7459 4060 7486 4076 7489

FLASH FLOOD...OBSERVED
EXPECTED RAINFALL RATE...0.25-0.5 INCHES IN 1 HOUR

$$

Staarmann
009 
WGUS51 KPHI 270140
FFWPHI
NJC019-027-035-037-270400-
/O.EXT.KPHI.FF.W.0013.000000T0000Z-230627T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
940 PM EDT Mon Jun 26 2023

The National Weather Service in Mount Holly has extended the

* Flash Flood Warning for...
  Morris County in northern New Jersey...
  Northern Somerset County in northern New Jersey...
  Northeastern Hunterdon County in northwestern New Jersey...
  Southeastern Sussex County in northwestern New Jersey...

* Until midnight EDT.

* At 940 PM EDT, local law enforcement reported thunderstorms 
  producing heavy rain across the warned area. Between 2.5 and 4.5 
  inches of rain have fallen. The expected rainfall rate is 0.25 to 
  0.5 inches in 1 hour. Additional rainfall amounts up to 0.5 inches 
  are possible in the warned area. Flash flooding is already 
  occurring.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Law enforcement reported.

  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, Hopatcong, 
  Florham Park, East Hanover, Lincoln Park, Manville, Kinnelon, and 
  Chatham.

This includes the following highways...
	Interstate 78 in New Jersey between mile markers 19 and 38.
	Interstate 80 in New Jersey between mile markers 27 and 48.
	Interstate 287 in New Jersey between mile markers 15 and 53.

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.

&&

LAT...LON 4091 7468 4099 7465 4110 7451 4110 7449
      4103 7450 4105 7445 4102 7443 4100 7430
      4097 7428 4093 7429 4091 7427 4091 7433
      4087 7434 4086 7432 4079 7437 4074 7437
      4069 7445 4055 7459 4060 7486 4076 7489

FLASH FLOOD...OBSERVED
EXPECTED RAINFALL RATE...0.25-0.5 INCHES IN 1 HOUR

$$

Staarmann
056 
WGUS71 KPHI 270403 RRD
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
1203 AM EDT Tue Jun 27 2023

NJC019-027-035-037-270413-
/O.EXP.KPHI.FF.W.0013.000000T0000Z-230627T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hunterdon NJ-Morris NJ-Somerset NJ-Sussex NJ-
1203 AM EDT Tue Jun 27 2023

...FLASH FLOOD WARNING HAS EXPIRED FOR MORRIS, NORTHERN SOMERSET, 
NORTHEASTERN HUNTERDON, AND SOUTHEASTERN SUSSEX COUNTIES...

The Flash FLood Warning has been replaced by an Areal Flood Warning, 
which is in effect until 700 AM EDT. Additional rainfall amounts of 
0.5 to 1.5 inches are possible. Areas of flooding of low lying and 
urban areas is possible overnight.

A Flood Watch remains in effect until 300 AM EDT for portions of New 
Jersey...and Pennsylvania.

LAT...LON 4091 7468 4099 7465 4110 7451 4110 7449
      4103 7450 4105 7445 4102 7443 4100 7430
      4097 7428 4093 7429 4091 7427 4091 7433
      4087 7434 4086 7432 4079 7437 4074 7437
      4069 7445 4055 7459 4060 7486 4076 7489

$$

Staarmann

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 26, 3:19 AM EDTSmall Craft AdvisoryPHI63 hr
Jun 26, 3:33 AM EDTFlood WatchPHIHunterdon, Mercer, Middlesex, Morris, Somerset, Sussex and 1 more23 hr
Jun 26, 9:18 AM EDTSevere Thunderstorm WarningPHIWarren42 min
Jun 26, 9:47 AM EDTSevere Thunderstorm WarningPHIMorris, Sussex, Warren43 min
Jun 26, 10:16 AM EDTSpecial Weather StatementPHICamden14 min
Jun 26, 10:43 AM EDTSpecial Weather StatementPHISussex32 min
Jun 26, 11:18 AM EDTSpecial Weather StatementPHISussex27 min
Jun 26, 11:53 AM EDTSpecial Weather StatementPHIMiddlesex22 min
Jun 26, 11:57 AM EDTSevere Thunderstorm WarningPHISussex18 min
Jun 26, 12:22 PM EDTSpecial Weather StatementPHIMiddlesex38 min
Jun 26, 2:02 PM EDTSpecial Weather StatementPHIHunterdon28 min
Jun 26, 2:32 PM EDTSpecial Marine WarningPHI43 min
Jun 26, 2:40 PM EDTSpecial Weather StatementPHIHunterdon35 min
Jun 26, 2:49 PM EDTSevere Thunderstorm WarningPHIHunterdon, Morris, Somerset, Warren41 min
Jun 26, 2:54 PM EDTAreal Flood AdvisoryPHIHunterdon95 min
Jun 26, 2:58 PM EDTSevere Thunderstorm WarningPHISussex, Warren47 min
Jun 26, 3:01 PM EDTSpecial Weather StatementPHICumberland29 min
Jun 26, 3:02 PM EDTTornado WarningPHIWarren28 min
Jun 26, 3:04 PM EDTSevere Thunderstorm WarningPHIMorris, Somerset41 min
Jun 26, 3:17 PM EDTTornado WarningPHIHunterdon, Somerset28 min
Jun 26, 3:21 PM EDTSpecial Weather StatementPHICamden24 min
Jun 26, 3:28 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden32 min
Jun 26, 3:40 PM EDTSevere Thunderstorm WarningPHIHunterdon, Morris, Somerset, Sussex50 min
Jun 26, 3:45 PM EDTSpecial Weather StatementPHIBurlington30 min
Jun 26, 3:48 PM EDTSevere Thunderstorm WarningPHIBurlington42 min
Jun 26, 3:56 PM EDTAreal Flood AdvisoryPHISussex, Warren2 hr
Jun 26, 3:59 PM EDTSpecial Weather StatementPHISussex, Warren46 min
Jun 26, 4:14 PM EDTSpecial Weather StatementPHIMercer31 min
Jun 26, 4:16 PM EDTAreal Flood AdvisoryPHIMorris, Somerset101 min
Jun 26, 4:24 PM EDTSpecial Weather StatementPHIBurlington36 min
Jun 26, 4:50 PM EDTAreal Flood AdvisoryPHIWarren73 min
Jun 26, 4:50 PM EDTSpecial Marine WarningPHI40 min
Jun 26, 5:01 PM EDTAreal Flood AdvisoryPHIMorris56 min
Jun 26, 5:09 PM EDTSevere Thunderstorm WarningPHICumberland, Salem25 min
Jun 26, 5:09 PM EDTSevere Thunderstorm WarningPHIMiddlesex, Morris, Somerset39 min
Jun 26, 5:22 PM EDTSpecial Marine WarningPHI23 min
Jun 26, 6:00 PM EDTAreal Flood AdvisoryPHIWarren4 hr
Jun 26, 6:03 PM EDTFlash Flood WarningPHIWarren6 hr
Jun 26, 6:08 PM EDTSpecial Weather StatementPHIHunterdon37 min
Jun 26, 6:15 PM EDTSpecial Weather StatementPHISalem30 min
Jun 26, 6:16 PM EDTAreal Flood AdvisoryPHIHunterdon, Morris, Sussex, Warren51 min
Jun 26, 6:55 PM EDTSpecial Weather StatementPHIHunterdon35 min
Jun 26, 7:07 PM EDTFlash Flood WarningPHIHunterdon, Morris, Sussex, Warren5 hr

Nearby

Flash Flood Warnings in New Jersey, 2023Every flash flood warning in 2023

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.