Alert archive / Pennsylvania / Flash Flood Warnings in 2023
Flash Flood Warning 33, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 8, 2023, 5:15 PM EDT for 4 counties in Pennsylvania. It was in force for 4 hr. 1 report 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
- Jul 8, 2023, 5:15 PM EDT (21:15 UTC)
- Expired
- Jul 8, 2023, 9:15 PM EDT
- In force
- 4 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Flood severity
- None
Counties Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA
The radar
The Philadelphia radar (KDIX), 81 km from the middle of the area, began a volume at 21:17 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 |
|---|---|---|---|
| Jul 8, 6:05 PM EDT | FLASH FLOOD | 1 Ene Upper Providence, PA | crum creek road just south of state road is flooded. picture sent 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
Washington/Dulle, VA (KIAD), launched 12:00Z, 9.3 hours before the alert went out and 210 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
- 305 J/kg
- Mixed-layer CIN
- -103 J/kg
- Mixed-layer LCL
- 1033 m above ground
- 0-6 km bulk shear
- 13 kt
- 0-1 km storm-relative helicity
- -21 m²/s²
- 0-3 km storm-relative helicity
- 44 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
436
WGUS51 KPHI 082115
FFWPHI
PAC029-045-091-101-090115-
/O.NEW.KPHI.FF.W.0033.230708T2115Z-230709T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
515 PM EDT Sat Jul 8 2023
The National Weather Service in Mount Holly has issued a
* Flash Flood Warning for...
East Central Chester County in southeastern Pennsylvania...
Central Delaware County in southeastern Pennsylvania...
Southern Montgomery County in southeastern Pennsylvania...
Western Philadelphia County in southeastern Pennsylvania...
* Until 915 PM EDT.
* At 515 PM EDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Between 0.5 and 1 inch of rain
has fallen. 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 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...
Philadelphia, Swarthmore, Narberth, Broomall, Newtown Square,
Trout Lake, Radnor Township, Drexel Hill, Bryn Mawr, Nether
Providence Township, Lima, and Gradyville.
This includes the following highways...
Interstate 476 in Pennsylvania between mile markers 2 and 13.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
Motorists should not attempt to drive around barricades or drive
cars through flooded areas.
&&
LAT...LON 4002 7550 4004 7542 4004 7534 4004 7532
4004 7525 3999 7523 3996 7526 3993 7530
3988 7538 3993 7549
FLASH FLOOD...RADAR INDICATED
$$
MLB3 follow-up statements
241
WGUS71 KPHI 082225
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
625 PM EDT Sat Jul 8 2023
PAC029-045-091-101-090115-
/O.CON.KPHI.FF.W.0033.000000T0000Z-230709T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Chester PA-Delaware PA-Montgomery PA-Philadelphia PA-
625 PM EDT Sat Jul 8 2023
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 915 PM EDT THIS
EVENING FOR EAST CENTRAL CHESTER, CENTRAL DELAWARE, SOUTHERN
MONTGOMERY, AND WESTERN PHILADELPHIA COUNTIES...
At 625 PM EDT, trained weather spotters reported flooded roads in
Upper Providence Township. Between 1.5 and 3 inches of rain have
fallen. Additional rainfall amounts up to 0.5 inches are possible in
the warned area. Flash flooding is already occurring.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Trained spotters reported.
IMPACT...Flooding of small creeks and streams, urban areas,
highways, streets, and underpasses as well as other
drainage and low lying areas.
Some locations that may experience flash flooding include...
Philadelphia, Swarthmore, Narberth, Broomall, Newtown Square,
Trout Lake, Radnor Township, Drexel Hill, Bryn Mawr, Nether
Providence Township, Lima, and Gradyville.
This includes the following highways...
Interstate 476 in Pennsylvania between mile markers 2 and 13.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
Motorists should not attempt to drive around barricades or drive
cars through flooded areas.
&&
LAT...LON 4002 7550 4004 7542 4004 7534 4004 7532
4004 7525 3999 7523 3996 7526 3993 7530
3988 7538 3993 7549
FLASH FLOOD...OBSERVED
$$
MLB621
WGUS71 KPHI 090047
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
847 PM EDT Sat Jul 8 2023
PAC029-091-101-090057-
/O.CAN.KPHI.FF.W.0033.000000T0000Z-230709T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Chester PA-Montgomery PA-Philadelphia PA-
847 PM EDT Sat Jul 8 2023
...FLASH FLOOD WARNING IS CANCELLED FOR EAST CENTRAL CHESTER,
SOUTHERN MONTGOMERY, AND WESTERN PHILADELPHIA COUNTIES...
Flooding is no longer expected to pose a threat. Please continue to
heed remaining road closures.
LAT...LON 4002 7541 4003 7533 4002 7532 4002 7531
3998 7528 3997 7528 3997 7526 3996 7526
3993 7530 3989 7538 3992 7547
$$
PAC045-090115-
/O.CON.KPHI.FF.W.0033.000000T0000Z-230709T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Delaware PA-
847 PM EDT Sat Jul 8 2023
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 915 PM EDT THIS
EVENING FOR CENTRAL DELAWARE COUNTY...
At 847 PM EDT, Doppler radar indicated thunderstorms producing heavy
rain across the warned area. Between 1.5 and 3 inches of rain have
fallen. Flash flooding is already occurring.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Radar.
IMPACT...Flooding of small creeks and streams, urban areas,
highways, streets, and underpasses as well as other
drainage and low lying areas.
Some locations that may experience flash flooding include...
Philadelphia, Swarthmore, Broomall, Newtown Square, Trout Lake,
Drexel Hill, Nether Providence Township, Radnor Township, Bryn
Mawr, Lima, Lansdowne, and Clifton Heights.
This includes the following highways...
Interstate 476 in Pennsylvania between mile markers 3 and 12.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
Be aware of your surroundings and do not drive on flooded roads.
&&
LAT...LON 4002 7541 4003 7533 4002 7532 4002 7531
3998 7528 3997 7528 3997 7526 3996 7526
3993 7530 3989 7538 3992 7547
FLASH FLOOD...RADAR INDICATED
$$
MLB062
WGUS71 KPHI 090107
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
907 PM EDT Sat Jul 8 2023
PAC045-090117-
/O.EXP.KPHI.FF.W.0033.000000T0000Z-230709T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Delaware PA-
907 PM EDT Sat Jul 8 2023
...FLASH FLOOD WARNING WILL EXPIRE AT 915 PM EDT THIS EVENING FOR
CENTRAL DELAWARE COUNTY...
The heavy rain has ended. Flooding is no longer expected to pose a
threat.
LAT...LON 4002 7541 4003 7533 4002 7532 4002 7531
3998 7528 3997 7528 3997 7526 3996 7526
3993 7530 3989 7538 3992 7547
$$
MLBThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 8, 1:28 PM EDT | Areal Flood Advisory | PHI | Philadelphia | 95 min |
| Jul 8, 2:05 PM EDT | Special Weather Statement | PHI | Philadelphia | 25 min |
| Jul 8, 2:28 PM EDT | Areal Flood Advisory | PHI | Philadelphia | 21 min |
| Jul 8, 2:40 PM EDT | Flash Flood Warning | PHI | Philadelphia | 4 hr |
| Jul 8, 3:00 PM EDT | Special Weather Statement | PHI | Philadelphia | 30 min |
| Jul 8, 3:17 PM EDT | Flood Watch | PHI | Berks, Bucks, Carbon, Chester, Delaware, Lehigh and 4 more | 31 hr |
| Jul 8, 3:44 PM EDT | Special Weather Statement | PHI | Bucks | 31 min |
| Jul 8, 3:52 PM EDT | Areal Flood Advisory | PHI | Bucks, Montgomery | 3 hr |
| Jul 8, 4:49 PM EDT | Special Weather Statement | PHI | Delaware | 26 min |
| Jul 8, 5:00 PM EDT | Areal Flood Advisory | PHI | Chester, Delaware, Montgomery, Philadelphia | 25 min |
| Jul 8, 5:19 PM EDT | Special Weather Statement | PHI | Delaware | 26 min |
| Jul 8, 5:30 PM EDT | Special Weather Statement | PHI | Chester | 30 min |
| Jul 8, 5:43 PM EDT | Areal Flood Advisory | PHI | Chester | 10 min |
| Jul 8, 5:51 PM EDT | Flash Flood Warning | PHI | Chester | 4 hr |
| Jul 8, 6:02 PM EDT | Special Weather Statement | PHI | Montgomery | 28 min |
| Jul 8, 6:33 PM EDT | Areal Flood Advisory | PHI | Chester, Montgomery | 3 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.