Flash Flood Warning 57, NWS Philadelphia/Mount Holly

Issued

Jul 21, 2026, 2:49 PM EDT (18:49 UTC)

Expired

Jul 21, 2026, 5:58 PM EDT

In force

3 hr

Issued by

NWS Philadelphia/Mount Holly

Area

Storm-based polygon

Flood severity

None

County Morris County, NJ

The Philadelphia radar (KDIX), 108 km from the middle of the area, began a volume at 18:53 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.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

201 
WGUS51 KPHI 211849
FFWPHI
NJC027-212300-
/O.NEW.KPHI.FF.W.0057.260721T1849Z-260721T2300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
249 PM EDT Tue Jul 21 2026

The National Weather Service in Mount Holly has issued a

* Flash Flood Warning for...
  Central Morris County in northern New Jersey...

* Until 700 PM EDT.

* At 249 PM EDT, Doppler radar 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 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...
  Dover, Hopatcong, Lincoln Park, Kinnelon, Boonton, Butler, 
  Wharton, Rockaway, Morris Plains, Mount Arlington, Mendham and 
  Mountain Lakes.

This includes the following highways...
	Interstate 287 in New Jersey between mile markers 42 and 53.
	Interstate 80 in New Jersey between mile markers 29 and 44.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4078 7482 4095 7462 4101 7439 4101 7436
      4100 7435 4100 7431 4100 7430 4099 7429
      4098 7430 4097 7428 4094 7428 4093 7429
      4092 7428 4091 7427 4090 7427 4091 7433
      4089 7434 4088 7434 4080 7459 4073 7473

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL RATE...1-2 INCHES IN 1 HOUR

$$

Kruzdlo

151 
WGUS71 KPHI 211938
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
338 PM EDT Tue Jul 21 2026

NJC027-212300-
/O.CON.KPHI.FF.W.0057.000000T0000Z-260721T2300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Morris NJ-
338 PM EDT Tue Jul 21 2026

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 7 PM EDT THIS EVENING 
FOR CENTRAL MORRIS COUNTY...

At 338 PM EDT, the New Jersey Department of Transportation reported 
flooding on I-80 at Exit 35.

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...
  Dover, Hopatcong, Lincoln Park, Kinnelon, Boonton, Butler, 
  Wharton, Rockaway, Morris Plains, Mount Arlington, Mendham and 
  Mountain Lakes.

This includes the following highways...
	Interstate 287 in New Jersey between mile markers 42 and 53.
	Interstate 80 in New Jersey between mile markers 28 and 44.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4078 7482 4095 7462 4101 7439 4101 7436
      4100 7435 4100 7431 4100 7430 4099 7429
      4098 7430 4097 7428 4094 7428 4093 7429
      4092 7428 4091 7427 4090 7427 4091 7433
      4089 7434 4088 7434 4080 7459 4073 7473

FLASH FLOOD...RADAR INDICATED

$$

Kruzdlo

366 
WGUS71 KPHI 212158
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
558 PM EDT Tue Jul 21 2026

NJC027-212208-
/O.CAN.KPHI.FF.W.0057.000000T0000Z-260721T2300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Morris NJ-
558 PM EDT Tue Jul 21 2026

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

The heavy rain has ended. Flooding is no longer expected to pose a 
threat.

A Flood Watch remains in effect until 200 AM EDT Wednesday for 
portions of northern Delaware, New Jersey, and southeast 
Pennsylvania.

&&

LAT...LON 4078 7482 4095 7462 4101 7439 4101 7436
      4100 7435 4100 7431 4100 7430 4099 7429
      4098 7430 4097 7428 4094 7428 4093 7429
      4092 7428 4091 7427 4090 7427 4091 7433
      4089 7434 4088 7434 4080 7459 4073 7473

$$

Kruzdlo

Flash Flood Warnings in New Jersey, 2026Every flash flood warning in 2026

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.