Alert archive / Pennsylvania / Areal Flood Warnings in 2021
Areal Flood Warning 18, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this areal flood warning at Aug 19, 2021, 10:40 AM EDT for Delaware County, Pennsylvania. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.
The area
The outline as issued.
The facts
- Issued
- Aug 19, 2021, 10:40 AM EDT (14:40 UTC)
- Expired
- Aug 19, 2021, 1:15 PM EDT
- In force
- 3 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Flood severity
- None
County Delaware County, PA
The radar
The Philadelphia radar (KDIX), 84 km from the middle of the area, began a volume at 14:41 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, 2.7 hours before the alert went out and 202 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
- 25 J/kg
- Mixed-layer CIN
- -104 J/kg
- Mixed-layer LCL
- 999 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 5 m²/s²
- 0-3 km storm-relative helicity
- 56 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
806
WGUS41 KPHI 191440
FLWPHI
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Flood Warning
National Weather Service Mount Holly NJ
1040 AM EDT Thu Aug 19 2021
PAC045-191745-
/O.NEW.KPHI.FA.W.0018.210819T1440Z-210819T1745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Delaware PA-
1040 AM EDT Thu Aug 19 2021
The National Weather Service in Mount Holly has issued a
* Flood Warning for Small stream in...
Central Delaware County in southeastern Pennsylvania...
* Until 145 PM EDT.
* At 1040 AM EDT, Ridley Creek at Media is currently in flood.
* For Ridley Creek at Media:
At 10:30am the stage was 7.48 feet.
Flood Stage is 7 feet.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
&&
LAT...LON 3986 7538 3987 7539 3990 7541 3993 7543
3994 7541 3993 7540 3992 7539 3989 7538
3987 7537
$$
BAH1 follow-up statement
989
WGUS81 KPHI 191715
FLSPHI
Flood Statement
National Weather Service Mount Holly NJ
115 PM EDT Thu Aug 19 2021
PAC045-191725-
/O.CAN.KPHI.FA.W.0018.000000T0000Z-210819T1745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Delaware PA-
115 PM EDT Thu Aug 19 2021
...THE SMALL STREAM FLOOD WARNING IS CANCELLED FOR CENTRAL DELAWARE
COUNTY...
Flood waters have receded as Ridley Creek at Media have fallen below
7 feet. Therefore, the flood warning has been canceled.
LAT...LON 3986 7538 3987 7539 3990 7541 3993 7543
3994 7541 3993 7540 3992 7539 3989 7538
3987 7537
$$
BAHThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 18, 8:53 PM EDT | Areal Flood Advisory | PHI | Berks | 3 hr |
| Aug 18, 9:10 PM EDT | Areal Flood Advisory | PHI | Lehigh, Monroe, Northampton | 3 hr |
| Aug 18, 9:30 PM EDT | Flash Flood Warning | PHI | Berks | 2 hr |
| Aug 18, 9:35 PM EDT | Areal Flood Advisory | PHI | Berks, Lehigh | 3 hr |
| Aug 18, 9:45 PM EDT | Areal Flood Advisory | PHI | Berks | 3 hr |
| Aug 18, 9:47 PM EDT | Special Weather Statement | PHI | Berks | 58 min |
| Aug 18, 10:16 PM EDT | Flash Flood Warning | PHI | Berks, Lehigh | 3 hr |
| Aug 18, 10:44 PM EDT | Flash Flood Warning | PHI | Lehigh, Monroe, Northampton | 4 hr |
| Aug 18, 10:50 PM EDT | Flash Flood Warning | PHI | Bucks, Chester, Montgomery | 4 hr |
| Aug 18, 11:19 PM EDT | Areal Flood Advisory | PHI | Bucks, Lehigh, Northampton | 3 hr |
| Aug 18, 11:19 PM EDT | Special Weather Statement | PHI | Bucks, Chester, Montgomery | 41 min |
| Aug 18, 11:47 PM EDT | Flash Flood Warning | PHI | Chester | 2 hr |
| Aug 19, 12:04 AM EDT | Special Weather Statement | PHI | Bucks, Delaware, Montgomery | 71 min |
| Aug 19, 12:26 AM EDT | Tornado Warning | PHI | Bucks, Montgomery | 34 min |
| Aug 19, 12:31 AM EDT | Flash Flood Warning | PHI | Bucks, Chester, Delaware, Montgomery | 4 hr |
| Aug 19, 12:44 AM EDT | River Flood Warning | PHI | Chester | 5 hr |
| Aug 19, 12:47 AM EDT | Tornado Warning | PHI | Chester, Delaware, Montgomery, Philadelphia | 28 min |
| Aug 19, 12:48 AM EDT | Tornado Warning | PHI | Bucks | 27 min |
| Aug 19, 1:14 AM EDT | Special Weather Statement | PHI | Bucks, Delaware, Philadelphia | 91 min |
| Aug 19, 1:30 AM EDT | Flash Flood Warning | PHI | Bucks, Delaware, Montgomery, Philadelphia | 4 hr |
| Aug 19, 2:05 AM EDT | Areal Flood Advisory | PHI | Bucks | 3 hr |
| Aug 19, 2:13 AM EDT | Flash Flood Warning | PHI | Bucks, Philadelphia | 4 hr |
| Aug 19, 4:33 AM EDT | Areal Flood Warning | PHI | Chester, Delaware | 4 hr |
| Aug 19, 6:09 AM EDT | Areal Flood Warning | PHI | Bucks, Philadelphia | 3 hr |
| Aug 19, 8:50 AM EDT | Areal Flood Warning | PHI | Montgomery, Philadelphia | 3 hr |
Nearby
Areal Flood Warnings in Pennsylvania, 2021Every areal flood warning in 2021
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.