Back to Home
Flash Flood Warning — Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA
Flash Flood Warning
Issued
10:21 p. m. CDT · dom., ago. 16 2026
Expires
2:30 a. m. CDT · lun., ago. 17 2026
Issuing Office
NWS KPHI

Affected Areas

Chester County, PA Delaware County, PA Montgomery County, PA Philadelphia County, PA

Official Bulletin

924
WGUS51 KPHI 170321
FFWPHI
PAC029-045-091-101-170730-
/O.NEW.KPHI.FF.W.0117.260817T0321Z-260817T0730Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
1121 PM EDT Sun Aug 16 2026

The National Weather Service in Mount Holly has issued a

* Flash Flood Warning for...
  Central Chester County in southeastern Pennsylvania...
  Northern Delaware County in southeastern Pennsylvania...
  Southern Montgomery County in southeastern Pennsylvania...
  Northwestern Philadelphia County in southeastern Pennsylvania...

* Until 330 AM EDT.

* At 1121 PM EDT, Doppler radar indicated heavy rain across the
  warned area. Between 1 and 2 inches of rain have fallen. The
  expected rainfall rate is 2 to 3 inches in 1 hour. Additional
  rainfall amounts of 0.5 to 1 inch are possible in the warned area.
  Flash flooding is ongoing or expected to begin shortly.

  HAZARD...Flash flooding caused by heavy rain.

  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...
  Philadelphia, West Chester, Norristown, Phoenixville, West
  Norriton, East Norriton, Coatesville, Westtown, Downingtown,
  Conshohocken, Royersford and Narberth.

This includes the following highways...
	Interstate 476 in Pennsylvania between mile markers 8 and 19.
	Interstate 76 in Pennsylvania between mile markers 327 and 338.
	Pennsylvania Turnpike between mile markers 305 and 334.

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 4008 7518 4007 7513 3994 7536 3989 7559
      3996 7595 4016 7575 4022 7559

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL RATE...2-3 INCHES IN 1 HOUR

$$

Guzzo