Alert archive / Pennsylvania / Areal Flood Warnings in 2021
Areal Flood Warning 53, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this areal flood warning at Oct 26, 2021, 12:31 AM EDT for 4 counties in Pennsylvania; New Castle County, Delaware. It was in force for 5 hr. 2 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
- Oct 26, 2021, 12:31 AM EDT (04:31 UTC)
- Expired
- Oct 26, 2021, 6:00 AM EDT
- In force
- 5 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Flood severity
- None
Counties New Castle County, DE, Berks County, PA, Chester County, PA, Delaware County, PA, Montgomery County, PA
The radar
The Philadelphia radar (KDIX), 129 km from the middle of the area, began a volume at 04:33 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 |
|---|---|---|---|
| Oct 26, 12:42 AM EDT | FLOOD | 1 Sw Coatesville, PA | STRODE AVENUE FLOODED. TIME BASED ON DISPATCH REPORT. |
| Oct 26, 12:45 AM EDT | FLOOD | 1 Nne Coatesville, PA | FLOODING ON MANOR ROAD AND BUTTERWORTH ROAD WITH TRAFFIC CONTROL REQUIRED. TIME BASED ON DISPATCH REPORT. |
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, 4.5 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
- 14 J/kg
- Mixed-layer CIN
- -15 J/kg
- Mixed-layer LCL
- 660 m above ground
- 0-6 km bulk shear
- 42 kt
- 0-1 km storm-relative helicity
- -130 m²/s²
- 0-3 km storm-relative helicity
- 70 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
169
WGUS41 KPHI 260431
FLWPHI
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Flood Warning
National Weather Service Mount Holly NJ
1231 AM EDT Tue Oct 26 2021
DEC003-PAC011-029-045-091-261015-
/O.NEW.KPHI.FA.W.0053.211026T0431Z-211026T1015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle DE-Berks PA-Chester PA-Delaware PA-Montgomery PA-
1231 AM EDT Tue Oct 26 2021
The National Weather Service in Mount Holly has issued a
* Flood Warning for...
Northwestern New Castle County in northern Delaware...
Berks County in eastern Pennsylvania...
Chester County in southeastern Pennsylvania...
West Central Delaware County in southeastern Pennsylvania...
Northwestern Montgomery County in southeastern Pennsylvania...
* Until 615 AM EDT.
* At 1231 AM EDT, Doppler radar indicated a band of heavy rain
moving slowly across the area. Flooding is ongoing or expected to
begin shortly in the warned area.
* Some locations that may experience flooding include...
Reading, Wilmington, Newark, West Chester, Pottstown,
Phoenixville, Coatesville, Westtown, Wyomissing, Downingtown,
Elsmere, and Kennett Square.
One to two inches of rain has already fallen and another two inches
of rain is possible through the overnight period.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles. It is difficult to see water on
roadways at night, so drive with extreme caution.
&&
LAT...LON 3972 7613 3976 7606 3985 7602 3987 7599
3995 7599 4004 7593 4011 7594 4014 7587
4032 7616 4054 7614 4058 7607 4057 7602
4061 7600 4066 7589 4042 7551 4024 7555
3993 7553 3966 7560 3946 7577 3972 7579
$$
PO2 follow-up statements
040
WGUS81 KPHI 260603
FLSPHI
Flood Statement
National Weather Service Mount Holly NJ
203 AM EDT Tue Oct 26 2021
DEC003-PAC011-029-045-091-261015-
/O.CON.KPHI.FA.W.0053.000000T0000Z-211026T1015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle DE-Berks PA-Chester PA-Delaware PA-Montgomery PA-
203 AM EDT Tue Oct 26 2021
...FLOOD WARNING REMAINS IN EFFECT UNTIL 615 AM EDT THIS MORNING FOR
NORTHWESTERN NEW CASTLE, BERKS, CHESTER, WEST CENTRAL DELAWARE, AND
NORTHWESTERN MONTGOMERY COUNTIES...
At 203 AM EDT, local law enforcement reported flooding in the
Coatesville area from heavy rainfall, with Route 82 closed. Between
1 and 2.5 inches of rain have fallen, with areas of flooding
expected to continue for the next several hours.
Some locations that may experience flooding include...
Reading, Wilmington, Newark, West Chester, Pottstown,
Phoenixville, Coatesville, Westtown, Wyomissing, Downingtown,
Elsmere, and Kennett Square.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
&&
LAT...LON 3972 7613 3976 7606 3985 7602 3987 7599
3995 7599 4004 7593 4011 7594 4014 7587
4032 7616 4054 7614 4058 7607 4057 7602
4061 7600 4066 7589 4042 7551 4024 7555
3993 7553 3966 7560 3946 7577 3972 7579
$$
CMS043
WGUS81 KPHI 261000
FLSPHI
Flood Statement
National Weather Service Mount Holly NJ
600 AM EDT Tue Oct 26 2021
DEC003-PAC011-029-045-091-261010-
/O.CAN.KPHI.FA.W.0053.000000T0000Z-211026T1015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle DE-Berks PA-Chester PA-Delaware PA-Montgomery PA-
600 AM EDT Tue Oct 26 2021
...FLOOD WARNING IS CANCELLED FOR NORTHWESTERN NEW CASTLE, BERKS,
CHESTER, WEST CENTRAL DELAWARE, AND NORTHWESTERN MONTGOMERY
COUNTIES...
The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed remaining road closures.
LAT...LON 3972 7613 3976 7606 3985 7602 3987 7599
3995 7599 4004 7593 4011 7594 4014 7587
4032 7616 4054 7614 4058 7607 4057 7602
4061 7600 4066 7589 4042 7551 4024 7555
3993 7553 3966 7560 3946 7577 3972 7579
$$
POThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 25, 8:33 PM EDT | Special Weather Statement | PHI | Northampton | 42 min |
| Oct 26, 2:08 AM EDT | Flash Flood Warning | PHI | Bucks | 4 hr |
| Oct 26, 6:09 AM EDT | Areal Flood Warning | PHI | Bucks | 3 hr |
| Oct 26, 10:27 AM EDT | Areal Flood Advisory | PHI | Monroe, Northampton | 4 hr |
| Oct 26, 12:20 PM EDT | Areal Flood Warning | PHI | Carbon, Monroe, Northampton | 7 hr |
| Oct 26, 1:53 AM EDT | Areal Flood Advisory | PHI | Sussex | 3 hr |
Nearby
Areal Flood Warnings in Pennsylvania, 2021Areal Flood Warnings in Delaware, 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.