Alert archive / Pennsylvania / Flash Flood Warnings in 2023
Flash Flood Warning 78, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 25, 2023, 4:55 PM EDT for Chester County, Pennsylvania. It was in force for 118 min. No storm report in the archive falls inside the area while it was in force.
The area
The outline as issued.
The facts
- Issued
- Jul 25, 2023, 4:55 PM EDT (20:55 UTC)
- Expired
- Jul 25, 2023, 6:53 PM EDT
- In force
- 118 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Flood severity
- None
County Chester County, PA
The radar
The Philadelphia radar (KDIX), 115 km from the middle of the area, began a volume at 20:59 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.
The nearest sounding before it
Washington/Dulle, VA (KIAD), launched 12:00Z, 8.9 hours before the alert went out and 180 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
- 591 J/kg
- Mixed-layer CIN
- -87 J/kg
- Mixed-layer LCL
- 1068 m above ground
- 0-6 km bulk shear
- 37 kt
- 0-1 km storm-relative helicity
- 17 m²/s²
- 0-3 km storm-relative helicity
- 52 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.5
The text
As transmitted.
309
WGUS51 KPHI 252055
FFWPHI
PAC029-260100-
/O.NEW.KPHI.FF.W.0078.230725T2055Z-230726T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
455 PM EDT Tue Jul 25 2023
The National Weather Service in Mount Holly has issued a
* Flash Flood Warning for...
Central Chester County in southeastern Pennsylvania...
* Until 900 PM EDT.
* At 455 PM EDT, Doppler radar indicated thunderstorms producing
heavy rain in Downington. Between 1 and 3 inches of rain have
fallen. Additional rainfall amounts of 0.5 to 1 inch are possible
in the warned area. Flash flooding is already occurring.
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...
West Chester, Coatesville, Marshallton, West Goshen, South
Coatesville, and Modena.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
Be aware of your surroundings and do not drive on flooded roads.
&&
LAT...LON 3998 7587 3997 7576 4000 7560 3991 7557
3994 7588
FLASH FLOOD...RADAR INDICATED
$$
RCM1 follow-up statement
815
WGUS71 KPHI 252253
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
653 PM EDT Tue Jul 25 2023
PAC029-252303-
/O.CAN.KPHI.FF.W.0078.000000T0000Z-230726T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Chester PA-
653 PM EDT Tue Jul 25 2023
...FLASH FLOOD WARNING IS CANCELLED FOR CENTRAL CHESTER COUNTY...
The heavy rain has ended and flood waters have receded. While local
creeks and streams will continue to run high, flooding is no longer
expected to pose a threat except near the Downingtown and Exton
areas where a river flood warning is in effect for the East Branch
Brandywine Creek near Downingtown.
LAT...LON 3998 7587 3997 7576 4000 7560 3991 7557
3994 7588
$$
RobertsonThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 25, 11:58 AM EDT | Special Weather Statement | PHI | Montgomery | 32 min |
| Jul 25, 12:07 PM EDT | Special Weather Statement | PHI | Berks | 23 min |
| Jul 25, 12:16 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Lehigh, Montgomery | 44 min |
| Jul 25, 12:31 PM EDT | Special Weather Statement | PHI | Berks | 29 min |
| Jul 25, 12:33 PM EDT | Special Weather Statement | PHI | Berks | 27 min |
| Jul 25, 12:37 PM EDT | Special Weather Statement | PHI | Carbon | 38 min |
| Jul 25, 12:47 PM EDT | Areal Flood Advisory | PHI | Bucks, Montgomery | 33 min |
| Jul 25, 12:56 PM EDT | Special Weather Statement | PHI | Northampton | 34 min |
| Jul 25, 1:00 PM EDT | Special Weather Statement | PHI | Berks | 30 min |
| Jul 25, 1:03 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Bucks, Chester, Lehigh, Montgomery | 42 min |
| Jul 25, 1:06 PM EDT | Severe Thunderstorm Warning | PHI | Carbon, Monroe, Northampton | 39 min |
| Jul 25, 1:10 PM EDT | Special Weather Statement | PHI | Delaware | 35 min |
| Jul 25, 1:12 PM EDT | Special Weather Statement | PHI | Monroe | 33 min |
| Jul 25, 1:20 PM EDT | Flash Flood Warning | PHI | Bucks, Montgomery | 5 hr |
| Jul 25, 1:27 PM EDT | Areal Flood Advisory | PHI | Berks | 3 hr |
| Jul 25, 1:27 PM EDT | Severe Thunderstorm Warning | PHI | Bucks | 48 min |
| Jul 25, 1:37 PM EDT | Areal Flood Advisory | PHI | Carbon | 3 hr |
| Jul 25, 1:38 PM EDT | Flash Flood Warning | PHI | Delaware | 4 hr |
| Jul 25, 1:41 PM EDT | Areal Flood Advisory | PHI | Lehigh, Northampton | 3 hr |
| Jul 25, 1:42 PM EDT | Special Weather Statement | PHI | Philadelphia | 33 min |
| Jul 25, 1:49 PM EDT | Special Weather Statement | PHI | Chester | 26 min |
| Jul 25, 1:54 PM EDT | Flash Flood Warning | PHI | Delaware, Philadelphia | 4 hr |
| Jul 25, 1:55 PM EDT | Areal Flood Advisory | PHI | Monroe | 2 hr |
| Jul 25, 2:06 PM EDT | Severe Thunderstorm Warning | PHI | Monroe | 39 min |
| Jul 25, 2:14 PM EDT | Severe Thunderstorm Warning | PHI | Chester, Montgomery | 46 min |
| Jul 25, 2:21 PM EDT | Areal Flood Advisory | PHI | Berks, Chester, Montgomery | 2 hr |
| Jul 25, 2:36 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Chester, Montgomery, Philadelphia | 39 min |
| Jul 25, 2:51 PM EDT | Flash Flood Warning | PHI | Chester, Montgomery | 3 hr |
| Jul 25, 2:57 PM EDT | Areal Flood Advisory | PHI | Chester | 3 hr |
| Jul 25, 3:06 PM EDT | Areal Flood Advisory | PHI | Bucks, Chester, Montgomery | 95 min |
| Jul 25, 3:13 PM EDT | Flash Flood Warning | PHI | Chester | 4 hr |
| Jul 25, 3:16 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Montgomery, Philadelphia | 44 min |
| Jul 25, 3:21 PM EDT | Severe Thunderstorm Warning | PHI | Chester, Delaware, Montgomery, Philadelphia | 39 min |
| Jul 25, 3:34 PM EDT | Flash Flood Warning | PHI | Chester, Montgomery | 3 hr |
| Jul 25, 3:58 PM EDT | Severe Thunderstorm Warning | PHI | Chester, Delaware, Montgomery, Philadelphia | 30 min |
| Jul 25, 4:04 PM EDT | Areal Flood Advisory | PHI | Bucks, Chester, Delaware, Montgomery, Philadelphia | 3 hr |
| Jul 25, 5:07 PM EDT | River Flood Warning | PHI | Chester | 6 hr |
Nearby
Flash Flood Warnings in Pennsylvania, 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.