Alert archive / Pennsylvania / Flash Flood Warnings in 2022
Flash Flood Warning 18, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this flash flood warning at Sep 6, 2022, 6:55 AM EDT for 4 counties in Pennsylvania. It was in force for 4 hr. 3 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
- Sep 6, 2022, 6:55 AM EDT (10:55 UTC)
- Expired
- Sep 6, 2022, 11:00 AM 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), 79 km from the middle of the area, began a volume at 10:54 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 |
|---|---|---|---|
| Sep 6, 7:54 AM EDT | FLASH FLOOD | 1 W Conshohocken, PA | WATER RESCUE ON CONSHOHOCKEN RD. |
| Sep 6, 8:15 AM EDT | FLASH FLOOD | 1 Nw Upper Darby, PA | COBBS CREEK AT PHILADELPHIA WENT ABOVE FLOOD STAGE AT 815 AM. |
| Sep 6, 9:12 AM EDT | FLASH FLOOD | Manayunk, PA | WISSAHICKON AT WISSAHICKON CREEK REACHED FLOOD STAGE 912 AM. |
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 00:00Z, 10.9 hours before the alert went out and 213 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
- 282 J/kg
- Mixed-layer CIN
- -8 J/kg
- Mixed-layer LCL
- 828 m above ground
- 0-6 km bulk shear
- 26 kt
- 0-1 km storm-relative helicity
- 41 m²/s²
- 0-3 km storm-relative helicity
- 69 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
The text
As transmitted.
833
WGUS51 KPHI 061055
FFWPHI
PAC029-045-091-101-061500-
/O.NEW.KPHI.FF.W.0018.220906T1055Z-220906T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
655 AM EDT Tue Sep 6 2022
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...
Southeastern Montgomery County in southeastern Pennsylvania...
Northwestern Philadelphia County in southeastern Pennsylvania...
* Until 1100 AM EDT.
* At 655 AM EDT, Doppler radar and automated rain gauges indicated
thunderstorms producing heavy rain across the warned area. Between
1 and 1.5 inches of rain have fallen. The expected rainfall rate
is 1 to 2 inches in 1 hour. Additional rainfall amounts of 1 to 2
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...
Philadelphia, Norristown, East Norriton, Yeadon, Westtown,
Conshohocken, Hatboro, Ambler, Swarthmore, Jenkintown, Narberth,
and East Lansdowne.
This includes the following highways...
Pennsylvania Turnpike between mile markers 330 and 346.
Interstate 76 in Pennsylvania between mile markers 329 and 342.
Interstate 476 in Pennsylvania between mile markers 3 and 19.
Northeast Extension between mile markers 21 and 23.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
&&
LAT...LON 3991 7558 4005 7542 4008 7536 4026 7522
4014 7501 4003 7513 3993 7527 3988 7545
FLASH FLOOD...RADAR AND GAUGE INDICATED
EXPECTED RAINFALL RATE...1-2 INCHES IN 1 HOUR
$$
Staarmann1 follow-up statement
924
WGUS71 KPHI 061452
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
1052 AM EDT Tue Sep 6 2022
PAC029-045-091-101-061502-
/O.EXP.KPHI.FF.W.0018.000000T0000Z-220906T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Chester PA-Delaware PA-Montgomery PA-Philadelphia PA-
1052 AM EDT Tue Sep 6 2022
...FLASH FLOOD WARNING WILL EXPIRE AT 11 AM EDT THIS MORNING FOR
EAST CENTRAL CHESTER, CENTRAL DELAWARE, SOUTHEASTERN MONTGOMERY, AND
NORTHWESTERN PHILADELPHIA COUNTIES...
The heavy rain was ending. Flooding is no longer expected to pose a
threat.
LAT...LON 3991 7558 4005 7542 4008 7536 4026 7522
4014 7501 4003 7513 3993 7527 3988 7545
$$
IovinoThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 6, 5:11 AM EDT | Areal Flood Advisory | PHI | Berks, Chester, Delaware, Montgomery | 4 hr |
| Sep 6, 6:32 AM EDT | Flash Flood Warning | PHI | Chester, Montgomery | 4 hr |
| Sep 6, 6:58 AM EDT | Areal Flood Advisory | PHI | Berks | 116 min |
| Sep 6, 7:00 AM EDT | Areal Flood Advisory | PHI | Lehigh, Northampton | 114 min |
| Sep 6, 7:15 AM EDT | Areal Flood Advisory | PHI | Bucks | 3 hr |
| Sep 6, 7:50 AM EDT | Areal Flood Advisory | PHI | Delaware, Philadelphia | 4 hr |
| Sep 6, 8:07 AM EDT | River Flood Warning | PHI | Chester | 4 hr |
Nearby
Flash Flood Warnings in Pennsylvania, 2022Every flash flood warning in 2022
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.