Alert archive / Pennsylvania / River Flood Warnings in 2021

River Flood Warning 73, NWS Philadelphia/Mount Holly

September 23, 2021Chester County, Pennsylvania

NWS Philadelphia/Mount Holly issued this river flood warning at Sep 23, 2021, 1:48 PM EDT for Chester County, Pennsylvania. It took effect at Sep 23, 2021, 2:36 PM EDT. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
Sep 23, 2021, 1:48 PM EDT (17:48 UTC)
In effect from
Sep 23, 2021, 2:36 PM EDT
Expired
Sep 23, 2021, 6:55 PM EDT
In force
4 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
Minor

County Chester County, PA

The radar

The Philadelphia radar (KDIX), 108 km from the middle of the area, began a volume at 17:46 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 river

Written for the forecast point East Branch Brandywine Creek below Downingtown (DWNP1). The gauge peaked at 8.82 ft at Sep 23, 2021, 4:00 PM EDT.

actionminormoderate24681009/2309/24
Action stage
6 ft
Minor stage
7 ft
Moderate stage
9 ft
Major stage
11 ft

This gauge today: stage, forecast and historic crests

Stage from the USGS instantaneous record for site 01480870, one reading an hour, from a day before the product to a day after it ended. Flood stages are today's.

The text

As transmitted.

167 
WGUS41 KPHI 231748
FLWPHI

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Flood Warning
National Weather Service Mount Holly NJ
148 PM EDT Thu Sep 23 2021

...The National Weather Service in Mount Holly NJ has issued a Flood 
Warning for the following rivers in Pennsylvania...

  East Branch Brandywine Creek Below Downingtown affecting Chester 
  County.

For the Brandywine Creek...including Downingtown...Minor flooding is 
forecast.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around...don't drown when encountering flooded roads. Most 
flood deaths occur in vehicles.

Additional information is available at www.weather.gov/phi.


PAC029-240145-
/O.NEW.KPHI.FL.W.0073.210923T1836Z-210924T0137Z/
/DWNP1.1.ER.210923T1836Z.210923T1900Z.210923T1936Z.NO/
148 PM EDT Thu Sep 23 2021

The National Weather Service in Mount Holly has issued a

* Flood Warning for
  the East Branch Brandywine Creek Below Downingtown.
* Until this evening.
* At 1:31 PM EDT Thursday the stage was 6.0 feet.
* Flood stage is 7.0 feet.
* Minor flooding is forecast.
* Forecast...The river is expected to rise above flood stage this 
  afternoon to a crest of 7.5 feet early this afternoon. It will 
  then fall below flood stage late this afternoon.
* Impact...At 6.0 feet, Open adjacent land next to the creek floods.
* Impact...At 8.0 feet, Dowlin Forge Road begins to flood.
* Flood History...This crest compares to a previous crest of 7.2 
  feet on 03/01/2021.

&&


Stream          Fld   Observed        Fcsts (unknown      Crest
Location        Stg   Stg Day/Time    d1   d2         Stg Time Date

East Branch Bran
Downingtown     7.0   6.0  Thu 1 pm   MSG  MSG        7.5 3pm 9/23





&&

LAT...LON 4002 7567 3993 7561 3991 7567 4001 7574

$$

NC
3 follow-up statements
586 
WGUS81 KPHI 231859
FLSPHI

Flood Statement
National Weather Service Mount Holly NJ
259 PM EDT Thu Sep 23 2021

...The Flood Warning is extended for the following rivers in 
Pennsylvania...

  East Branch Brandywine Creek Below Downingtown affecting Chester 
  County.

For the Brandywine Creek...including Downingtown...Minor flooding is 
forecast.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around...don't drown when encountering flooded roads. Most 
flood deaths occur in vehicles.

Additional information is available at www.weather.gov/phi.


PAC029-240215-
/O.EXT.KPHI.FL.W.0073.000000T0000Z-210924T0206Z/
/DWNP1.1.ER.210923T1800Z.210923T1900Z.210923T2006Z.NO/
259 PM EDT Thu Sep 23 2021

...The Flood Warning is now in effect until late this evening...

The Flood Warning continues for
  the East Branch Brandywine Creek Below Downingtown.
* Until this evening.
* At 2:45 PM EDT Thursday the stage was 8.1 feet.
* Flood stage is 7.0 feet.
* Minor flooding is occurring and minor flooding is forecast.
* Recent Activity...The maximum river stage in the 24 hours ending 
  at 2:45 PM EDT Thursday was 8.1 feet.
* Forecast...The river is expected to rise to a crest of 8.1 feet 
  shortly. It will then fall below flood stage late this afternoon.
* Impact...At 6.0 feet, Open adjacent land next to the creek floods.
* Impact...At 8.0 feet, Dowlin Forge Road begins to flood.
* Impact...At 9.0 feet, High water on the Brandywine sends backwater 
  up Beaver Creek. Beaver Creek floods inundating parks and the 
  Downingtown Little League fields.
* Flood History...This crest compares to a previous crest of 7.9 
  feet on 08/19/2021.

&&


Stream          Fld   Observed        Fcsts (unknown      Crest
Location        Stg   Stg Day/Time    d1   d2         Stg Time Date

East Branch Bran
Downingtown     7.0   8.1  Thu 2 pm   MSG  MSG        8.1 3pm 9/23





&&

LAT...LON 4002 7567 3993 7561 3991 7567 4001 7574

$$

NC
931 
WGUS81 KPHI 231956
FLSPHI

Flood Statement
National Weather Service Mount Holly NJ
356 PM EDT Thu Sep 23 2021

...The Flood Warning is extended for the following rivers in 
Pennsylvania...

  East Branch Brandywine Creek Below Downingtown affecting Chester 
  County.

For the Brandywine Creek...including Downingtown...Minor flooding is 
forecast.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around...don't drown when encountering flooded roads. Most 
flood deaths occur in vehicles.

Additional information is available at www.weather.gov/phi.


PAC029-240315-
/O.EXT.KPHI.FL.W.0073.000000T0000Z-210924T0310Z/
/DWNP1.1.ER.210923T1800Z.210923T2000Z.210923T2110Z.NO/
356 PM EDT Thu Sep 23 2021

...The Flood Warning is now in effect until late this evening...

The Flood Warning continues for
  the East Branch Brandywine Creek Below Downingtown.
* Until this evening.
* At 3:45 PM EDT Thursday the stage was 8.7 feet.
* Flood stage is 7.0 feet.
* Minor flooding is occurring and minor flooding is forecast.
* Recent Activity...The maximum river stage in the 24 hours ending 
  at 3:45 PM EDT Thursday was 8.7 feet.
* Forecast...The river is expected to rise to a crest of 8.8 feet 
  late this afternoon. It will then fall below flood stage late this 
  afternoon.
* Impact...At 6.0 feet, Open adjacent land next to the creek floods.
* Impact...At 8.0 feet, Dowlin Forge Road begins to flood.
* Impact...At 9.0 feet, High water on the Brandywine sends backwater 
  up Beaver Creek. Beaver Creek floods inundating parks and the 
  Downingtown Little League fields.
* Flood History...This crest compares to a previous crest of 9.2 
  feet on 10/23/2003.

&&


Stream          Fld   Observed        Fcsts (unknown      Crest
Location        Stg   Stg Day/Time    d1   d2         Stg Time Date

East Branch Bran
Downingtown     7.0   8.7  Thu 3 pm   MSG  MSG        8.8 4pm 9/23





&&

LAT...LON 4002 7567 3993 7561 3991 7567 4001 7574

$$

NC
086 
WGUS81 KPHI 232255
FLSPHI

Flood Statement
National Weather Service Mount Holly NJ
655 PM EDT Thu Sep 23 2021

...The Flood Warning is cancelled for the following rivers in 
Pennsylvania...

  East Branch Brandywine Creek Below Downingtown affecting Chester 
  County.

PAC029-240000-
/O.CAN.KPHI.FL.W.0073.000000T0000Z-210923T2255Z/
/DWNP1.1.ER.210923T1800Z.210923T2030Z.210923T2300Z.NO/
655 PM EDT Thu Sep 23 2021

...The Flood Warning for the East Branch Brandywine Creek Below 
Downingtown has been cancelled...

The Flood Warning is cancelled for
  the East Branch Brandywine Creek Below Downingtown.
* At 6:45 PM EDT Thursday the stage was 7.0 feet.
* Flood stage is 7.0 feet.
* Forecast...The river has fallen below flood stage and will remain 
  below flood stage.

&&


Stream          Fld   Observed        Fcsts (unknown      Crest
Location        Stg   Stg Day/Time    d1   d2         Stg Time Date

East Branch Bran
Downingtown     7.0   7.0  Thu 6 pm   MSG  MSG        7.0 7pm 9/23





&&

LAT...LON 4002 7567 3993 7561 3991 7567 4001 7574

$$

NC

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 23, 9:12 AM EDTCoastal Flood AdvisoryPHIBucks, Delaware, Philadelphia10 hr
Sep 23, 10:52 AM EDTAreal Flood AdvisoryPHIChester3 hr
Sep 23, 11:33 AM EDTAreal Flood AdvisoryPHIBerks, Chester, Delaware, Montgomery, Philadelphia3 hr
Sep 23, 11:40 AM EDTAreal Flood AdvisoryPHIBerks, Bucks, Carbon, Lehigh, Montgomery, Northampton3 hr
Sep 23, 11:57 AM EDTFlash Flood WarningPHIChester, Delaware3 hr
Sep 23, 12:12 PM EDTSevere Thunderstorm WarningPHIChester, Delaware, Montgomery, Philadelphia48 min
Sep 23, 12:28 PM EDTFlash Flood WarningPHIChester, Delaware, Montgomery, Philadelphia4 hr
Sep 23, 12:54 PM EDTSpecial Weather StatementPHIPhiladelphia51 min
Sep 23, 12:56 PM EDTAreal Flood AdvisoryPHIBucks, Carbon, Lehigh, Monroe, Montgomery, Northampton and 1 more3 hr
Sep 23, 12:57 PM EDTSpecial Weather StatementPHIBucks33 min
Sep 23, 1:13 PM EDTSevere Thunderstorm WarningPHIBucks, Delaware, Montgomery, Philadelphia47 min
Sep 23, 1:42 PM EDTFlash Flood WarningPHIBucks, Delaware, Montgomery, Philadelphia4 hr
Sep 23, 1:58 PM EDTSpecial Weather StatementPHIBucks32 min
Sep 23, 2:37 PM EDTAreal Flood AdvisoryPHIBucks, Northampton3 hr
Sep 23, 3:26 PM EDTFlash Flood WarningPHIBucks2 hr
Sep 23, 4:26 PM EDTAreal Flood WarningPHIChester, Delaware, Montgomery, Philadelphia80 min
Sep 23, 7:18 PM EDTAreal Flood WarningPHIBerks, Montgomery36 min

Nearby

River Flood Warnings in Pennsylvania, 2021Every river 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; radar from the NEXRAD Level II archive; the gauge from the NWS water service and the USGS.