Alert archive / Pennsylvania / Areal Flood Warnings in 2021
Areal Flood Warning 51, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this areal flood warning at Sep 23, 2021, 7:18 PM EDT for Berks County, Montgomery County, Pennsylvania. It was in force for 36 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
- Sep 23, 2021, 7:18 PM EDT (23:18 UTC)
- Expired
- Sep 23, 2021, 7:54 PM EDT
- In force
- 36 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Flood severity
- None
Counties Berks County, PA, Montgomery County, PA
The radar
The Philadelphia radar (KDIX), 117 km from the middle of the area, began a volume at 23:19 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, 11.3 hours before the alert went out and 212 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 517 m above ground
- 0-6 km bulk shear
- 58 kt
- 0-1 km storm-relative helicity
- -71 m²/s²
- 0-3 km storm-relative helicity
- 88 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 2.0
The text
As transmitted.
477
WGUS41 KPHI 232318
FLWPHI
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Flood Warning
National Weather Service Mount Holly NJ
718 PM EDT Thu Sep 23 2021
PAC011-091-240215-
/O.NEW.KPHI.FA.W.0051.210923T2318Z-210924T0215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Berks PA-Montgomery PA-
718 PM EDT Thu Sep 23 2021
The National Weather Service in Mount Holly has issued a
* Flood Warning for Small stream in...
East Central Berks County in eastern Pennsylvania...
Northwestern Montgomery County in southeastern Pennsylvania...
* Until 1015 PM EDT.
* At 718 PM EDT, Around 2 inches of rain fell earlier this afternoon
in the vicinity of Manatawny Creek. Minor flooding is expected
along the creek over the next few hours as water levels remain
elevated from the earlier rainfall.
* For Manatawny Creek at Spangville:
At 7:00pm the stage was 5.95 feet.
Flood Stage is 6 feet.
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 4028 7574 4033 7576 4040 7577 4045 7567
4045 7566 4044 7566 4036 7571 4031 7570
4029 7567 4029 7566 4026 7565 4024 7565
$$
NC1 follow-up statement
671
WGUS81 KPHI 232354
FLSPHI
Flood Statement
National Weather Service Mount Holly NJ
754 PM EDT Thu Sep 23 2021
PAC011-091-240004-
/O.CAN.KPHI.FA.W.0051.000000T0000Z-210924T0215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Berks PA-Montgomery PA-
754 PM EDT Thu Sep 23 2021
...THE SMALL STREAM FLOOD WARNING IS CANCELLED FOR EAST CENTRAL
BERKS AND NORTHWESTERN MONTGOMERY COUNTIES...
Flood waters have receded. Flooding is no longer expected to pose a
threat. Please continue to heed remaining road closures.
LAT...LON 4028 7574 4033 7576 4040 7577 4045 7567
4045 7566 4044 7566 4036 7571 4031 7570
4029 7567 4029 7566 4026 7565 4024 7565
$$
NCThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 23, 9:12 AM EDT | Coastal Flood Advisory | PHI | Bucks, Delaware, Philadelphia | 10 hr |
| Sep 23, 10:52 AM EDT | Areal Flood Advisory | PHI | Chester | 3 hr |
| Sep 23, 11:33 AM EDT | Areal Flood Advisory | PHI | Berks, Chester, Delaware, Montgomery, Philadelphia | 3 hr |
| Sep 23, 11:40 AM EDT | Areal Flood Advisory | PHI | Berks, Bucks, Carbon, Lehigh, Montgomery, Northampton | 3 hr |
| Sep 23, 11:57 AM EDT | Flash Flood Warning | PHI | Chester, Delaware | 3 hr |
| Sep 23, 12:12 PM EDT | Severe Thunderstorm Warning | PHI | Chester, Delaware, Montgomery, Philadelphia | 48 min |
| Sep 23, 12:28 PM EDT | Flash Flood Warning | PHI | Chester, Delaware, Montgomery, Philadelphia | 4 hr |
| Sep 23, 12:54 PM EDT | Special Weather Statement | PHI | Philadelphia | 51 min |
| Sep 23, 12:56 PM EDT | Areal Flood Advisory | PHI | Bucks, Carbon, Lehigh, Monroe, Montgomery, Northampton and 1 more | 3 hr |
| Sep 23, 12:57 PM EDT | Special Weather Statement | PHI | Bucks | 33 min |
| Sep 23, 1:13 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Delaware, Montgomery, Philadelphia | 47 min |
| Sep 23, 1:42 PM EDT | Flash Flood Warning | PHI | Bucks, Delaware, Montgomery, Philadelphia | 4 hr |
| Sep 23, 1:48 PM EDT | River Flood Warning | PHI | Chester | 5 hr |
| Sep 23, 1:58 PM EDT | Special Weather Statement | PHI | Bucks | 32 min |
| Sep 23, 2:37 PM EDT | Areal Flood Advisory | PHI | Bucks, Northampton | 3 hr |
| Sep 23, 3:26 PM EDT | Flash Flood Warning | PHI | Bucks | 2 hr |
| Sep 23, 4:26 PM EDT | Areal Flood Warning | PHI | Chester, Delaware, Montgomery, Philadelphia | 80 min |
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.