Alert archive / Pennsylvania / River Flood Warnings in 2021

River Flood Warning 38, NWS Philadelphia/Mount Holly

September 1, 2021Montgomery County, Pennsylvania

NWS Philadelphia/Mount Holly issued this river flood warning at Sep 1, 2021, 4:20 PM EDT for Montgomery County, Pennsylvania. It took effect at Sep 1, 2021, 6:52 PM EDT. It was in force for 20 hr.

The area

The outline as issued.

The facts

Issued: Sep 1, 2021, 4:20 PM EDT (20:20 UTC)
In effect from: Sep 1, 2021, 6:52 PM EDT
Expired: Sep 2, 2021, 2:47 PM EDT
In force: 20 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Flood severity: Moderate

County Montgomery County, PA

The radar

The Philadelphia radar (KDIX), 93 km from the middle of the area, began a volume at 20:19 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 river

Written for the forecast point Perkiomen Creek at Graterford (GRAP1). The gauge peaked at 24.23 ft at Sep 2, 2021, 3:00 AM EDT.

Action stage: 8 ft
Minor stage: 11 ft
Moderate stage: 13 ft
Major stage: 16 ft

This gauge today: stage, forecast and historic crests

Stage from the USGS instantaneous record for site 01473000, 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.

244 
WGUS41 KPHI 012020
FLWPHI

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Flood Warning
National Weather Service Mount Holly NJ
420 PM EDT Wed Sep 1 2021

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

  Perkiomen Creek At Graterford affecting Montgomery County.

For the Perkiomen Creek...including Graterford...Moderate 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.


PAC091-020830-
/O.NEW.KPHI.FL.W.0038.210902T0200Z-210902T2252Z/
/GRAP1.2.ER.210902T0200Z.210902T1200Z.210902T1651Z.NO/
420 PM EDT Wed Sep 1 2021

The National Weather Service in Mount Holly has issued a

* Flood Warning for
  the Perkiomen Creek At Graterford.
* From this evening to Thursday evening.
* At 3:15 PM EDT Wednesday the stage was 1.5 feet.
* Flood stage is 11.0 feet.
* Moderate flooding is forecast.
* Forecast...The river is expected to rise above flood stage late 
  this evening to a crest of 15.7 feet tomorrow morning. It will 
  then fall below flood stage early tomorrow afternoon.
* Impact...At 8.0 feet, Park Avenue in Schwenksville is flooded. The 
  Perkiomen Trail is flooded in Perkiomen Township at Plank Road and 
  Route 113. Ninth Avenue begins to flood in Collegeville.
* Impact...At 11.0 feet, Graterford Road and Penitentiary Bridge are 
  closed due to flooding.
* Impact...At 12.0 feet, Portions of Central Perkiomen Park in 
  Collegeville are flooded. Flood waters expand onto and to the west 
  of First Avenue in Collegeville.
* Impact...At 13.0 feet, First Avenue in Collegeville becomes 
  impassable.
* Impact...At 14.0 feet, Storm sewers back up in Collegeville and 
  flood Route 29.
* Impact...At 15.0 feet, East Main Street in Collegeville floods.
* Impact...At 16.0 feet, Collegeville businesses on Route 29, 
  between East Ninth Street and East Main Street, begin to take on 
  water.
* Flood History...This crest compares to a previous crest of 15.7 
  feet on 10/19/1996.

&&


               Fld   Observed           Forecasts (2 pm EDT)     
Location       Stg   Stg   Day/Time     Thu   Fri   Sat          

Perkiomen Creek
Graterford     11.0  1.5   Wed 3 pm EDT 9.9   4.7   2.6          





&&

LAT...LON 4024 7549 4024 7542 4011 7542 4012 7547

$$

Kruzdlo

7 follow-up statements

355 
WGUS81 KPHI 012252
FLSPHI

Flood Statement
National Weather Service Mount Holly NJ
652 PM EDT Wed Sep 1 2021

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

  Perkiomen Creek At Graterford affecting Montgomery County.

For the Perkiomen Creek...including Graterford...Major 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.


PAC091-021100-
/O.EXT.KPHI.FL.W.0038.210901T2252Z-210902T2309Z/
/GRAP1.3.ER.210901T2209Z.210902T0600Z.210902T1709Z.NO/
652 PM EDT Wed Sep 1 2021

...The Flood Warning is now in effect until tomorrow evening...

The Flood Warning continues for
  the Perkiomen Creek At Graterford.
* From this evening to Thursday evening.
* At 6:32 PM EDT Wednesday the stage was 12.3 feet.
* Flood stage is 11.0 feet.
* Minor flooding is occurring and major flooding is forecast.
* Recent Activity...The maximum river stage in the 24 hours ending 
  at 6:32 PM EDT Wednesday was 12.3 feet.
* Forecast...The river is expected to rise to a crest of 16.5 feet 
  just after midnight tonight. It will then fall below flood stage 
  early tomorrow afternoon.
* Impact...At 8.0 feet, Park Avenue in Schwenksville is flooded. The 
  Perkiomen Trail is flooded in Perkiomen Township at Plank Road and 
  Route 113. Ninth Avenue begins to flood in Collegeville.
* Impact...At 11.0 feet, Graterford Road and Penitentiary Bridge are 
  closed due to flooding.
* Impact...At 12.0 feet, Portions of Central Perkiomen Park in 
  Collegeville are flooded. Flood waters expand onto and to the west 
  of First Avenue in Collegeville.
* Impact...At 13.0 feet, First Avenue in Collegeville becomes 
  impassable.
* Impact...At 14.0 feet, Storm sewers back up in Collegeville and 
  flood Route 29.
* Impact...At 15.0 feet, East Main Street in Collegeville floods.
* Impact...At 16.0 feet, Collegeville businesses on Route 29, 
  between East Ninth Street and East Main Street, begin to take on 
  water.
* Flood History...This crest compares to a previous crest of 16.5 
  feet on 01/19/1996.

&&


               Fld   Observed           Forecasts (8 pm EDT)     
Location       Stg   Stg   Day/Time     Thu   Fri   Sat          

Perkiomen Creek
Graterford     11.0  12.3  Wed 6 pm EDT 7.2   4.1   MSG          





&&

LAT...LON 4024 7549 4024 7542 4011 7542 4012 7547

$$

CMS

724 
WGUS81 KPHI 020153
FLSPHI

Flood Statement
National Weather Service Mount Holly NJ
953 PM EDT Wed Sep 1 2021

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

  Perkiomen Creek At Graterford affecting Montgomery County.

For the Perkiomen Creek...including Graterford...Major flooding is 
forecast.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

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


PAC091-021400-
/O.EXT.KPHI.FL.W.0038.000000T0000Z-210903T0200Z/
/GRAP1.3.ER.210901T2209Z.210902T0600Z.210902T2000Z.NR/
953 PM EDT Wed Sep 1 2021

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

The Flood Warning continues for
  the Perkiomen Creek At Graterford.
* Until Thursday evening.
* At 9:31 PM EDT Wednesday the stage was 18.8 feet.
* Flood stage is 11.0 feet.
* Major flooding is occurring and major flooding is forecast. This 
  approaches the flood of record.
* Recent Activity...The maximum river stage in the 24 hours ending 
  at 9:31 PM EDT Wednesday was 18.8 feet.
* Forecast...The river is expected to rise to a crest of 19.2 feet 
  just after midnight tonight. It will then fall below flood stage 
  tomorrow afternoon.
* Impact...At 8.0 feet, Park Avenue in Schwenksville is flooded. The 
  Perkiomen Trail is flooded in Perkiomen Township at Plank Road and 
  Route 113. Ninth Avenue begins to flood in Collegeville.
* Impact...At 11.0 feet, Graterford Road and Penitentiary Bridge are 
  closed due to flooding.
* Impact...At 12.0 feet, Portions of Central Perkiomen Park in 
  Collegeville are flooded. Flood waters expand onto and to the west 
  of First Avenue in Collegeville.
* Impact...At 13.0 feet, First Avenue in Collegeville becomes 
  impassable.
* Impact...At 14.0 feet, Storm sewers back up in Collegeville and 
  flood Route 29.
* Impact...At 15.0 feet, East Main Street in Collegeville floods.
* Impact...At 16.0 feet, Collegeville businesses on Route 29, 
  between East Ninth Street and East Main Street, begin to take on 
  water.
* Impact...At 18.0 feet, Smaller tributaries are affected by high 
  water from the Perkiomen. Flooding is possible near the Route 113 
  Bridge in Perkiomen Township.
* Impact...At 19.0 feet, The Schwensville Sewer and Water Plant 
  floods as does Route 73/Haldeman Road.
* Flood History...This crest compares to a previous crest of 19.3 
  feet on 08/05/2020.

&&


               Fld   Observed           Forecasts (8 pm EDT)     
Location       Stg   Stg   Day/Time     Thu   Fri   Sat          

Perkiomen Creek
Graterford     11.0  18.8  Wed 9 pm EDT 8.8   4.5   2.6          





&&

LAT...LON 4024 7549 4024 7542 4011 7542 4012 7547

$$

Meola

729 
WGUS81 KPHI 020217
FLSPHI

Flood Statement
National Weather Service Mount Holly NJ
1017 PM EDT Wed Sep 1 2021

...The Flood Warning continues for the following rivers in 
Pennsylvania...

  Perkiomen Creek At Graterford affecting Montgomery County.

For the Perkiomen Creek...including Graterford...Major flooding is 
forecast.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

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


PAC091-021430-
/O.CON.KPHI.FL.W.0038.000000T0000Z-210903T0200Z/
/GRAP1.3.ER.210901T2209Z.210902T0400Z.210902T2000Z.NR/
1017 PM EDT Wed Sep 1 2021

...The Flood Warning remains in effect...

The Flood Warning continues for
  the Perkiomen Creek At Graterford.
* Until Thursday evening.
* At 9:46 PM EDT Wednesday the stage was 19.3 feet.
* Flood stage is 11.0 feet.
* Major flooding is occurring and major flooding is forecast. This 
  will exceed the flood of record.
* Recent Activity...The maximum river stage in the 24 hours ending 
  at 9:46 PM EDT Wednesday was 19.3 feet.
* Forecast...The river is expected to rise to a crest of 20.5 feet 
  just after midnight tonight. It will then fall below flood stage 
  tomorrow afternoon.
* Impact...At 8.0 feet, Park Avenue in Schwenksville is flooded. The 
  Perkiomen Trail is flooded in Perkiomen Township at Plank Road and 
  Route 113. Ninth Avenue begins to flood in Collegeville.
* Impact...At 11.0 feet, Graterford Road and Penitentiary Bridge are 
  closed due to flooding.
* Impact...At 12.0 feet, Portions of Central Perkiomen Park in 
  Collegeville are flooded. Flood waters expand onto and to the west 
  of First Avenue in Collegeville.
* Impact...At 13.0 feet, First Avenue in Collegeville becomes 
  impassable.
* Impact...At 14.0 feet, Storm sewers back up in Collegeville and 
  flood Route 29.
* Impact...At 15.0 feet, East Main Street in Collegeville floods.
* Impact...At 16.0 feet, Collegeville businesses on Route 29, 
  between East Ninth Street and East Main Street, begin to take on 
  water.
* Impact...At 18.0 feet, Smaller tributaries are affected by high 
  water from the Perkiomen. Flooding is possible near the Route 113 
  Bridge in Perkiomen Township.
* Impact...At 19.0 feet, The Schwensville Sewer and Water Plant 
  floods as does Route 73/Haldeman Road.
* Flood History...This crest compares to a previous crest of 19.3 
  feet on 08/05/2020.

&&


               Fld   Observed           Forecasts (8 pm EDT)     
Location       Stg   Stg   Day/Time     Thu   Fri   Sat          

Perkiomen Creek
Graterford     11.0  19.3  Wed 9 pm EDT 8.8   4.5   2.6          





&&

LAT...LON 4024 7549 4024 7542 4011 7542 4012 7547

$$

Meola

570 
WGUS81 KPHI 020430
FLSPHI

Flood Statement
National Weather Service Mount Holly NJ
1230 AM EDT Thu Sep 2 2021

...The Flood Warning continues for the following rivers in 
Pennsylvania...

  Perkiomen Creek At Graterford affecting Montgomery County.

For the Perkiomen Creek...including Graterford...Major flooding is 
forecast.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

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


PAC091-021630-
/O.CON.KPHI.FL.W.0038.000000T0000Z-210903T0200Z/
/GRAP1.3.ER.210901T2209Z.210902T0600Z.210902T2000Z.NR/
1230 AM EDT Thu Sep 2 2021

...The Flood Warning remains in effect...

The Flood Warning continues for
  the Perkiomen Creek At Graterford.
* Until this evening.
* At 10:30 PM EDT Wednesday the stage was 20.6 feet.
* Flood stage is 11.0 feet.
* Major flooding is occurring and major flooding is forecast. This 
  exceeds the flood of record.
* Recent Activity...The maximum river stage in the 24 hours ending 
  at 10:30 PM EDT Wednesday was 20.6 feet.
* Forecast...The river is expected to rise to a crest of 22.0 feet 
  early this morning. It will then fall below flood stage late this 
  afternoon.
* Impact...At 8.0 feet, Park Avenue in Schwenksville is flooded. The 
  Perkiomen Trail is flooded in Perkiomen Township at Plank Road and 
  Route 113. Ninth Avenue begins to flood in Collegeville.
* Impact...At 11.0 feet, Graterford Road and Penitentiary Bridge are 
  closed due to flooding.
* Impact...At 12.0 feet, Portions of Central Perkiomen Park in 
  Collegeville are flooded. Flood waters expand onto and to the west 
  of First Avenue in Collegeville.
* Impact...At 13.0 feet, First Avenue in Collegeville becomes 
  impassable.
* Impact...At 14.0 feet, Storm sewers back up in Collegeville and 
  flood Route 29.
* Impact...At 15.0 feet, East Main Street in Collegeville floods.
* Impact...At 16.0 feet, Collegeville businesses on Route 29, 
  between East Ninth Street and East Main Street, begin to take on 
  water.
* Impact...At 18.0 feet, Smaller tributaries are affected by high 
  water from the Perkiomen. Flooding is possible near the Route 113 
  Bridge in Perkiomen Township.
* Impact...At 19.0 feet, The Schwensville Sewer and Water Plant 
  floods as does Route 73/Haldeman Road.
* Flood History...This crest compares to a previous crest of 19.3 
  feet on 08/05/2020.

&&


               Fld   Observed           Forecasts (2 am EDT)     
Location       Stg   Stg   Day/Time     Fri   Sat   Sun          

Perkiomen Creek
Graterford     11.0  20.6  Wed 10 pm ED 7.6   3.6   MSG          





&&

LAT...LON 4024 7549 4024 7542 4011 7542 4012 7547

$$

Meola

588 
WGUS81 KPHI 020728
FLSPHI

Flood Statement
National Weather Service Mount Holly NJ
328 AM EDT Thu Sep 2 2021

...The Flood Warning continues for the following rivers in 
Pennsylvania...

  Perkiomen Creek At Graterford affecting Montgomery County.

For the Perkiomen Creek...including Graterford...Major flooding is 
forecast.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Motorists should not attempt to drive around barricades or drive 
cars through flooded areas.

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

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

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


PAC091-021930-
/O.EXT.KPHI.FL.W.0038.000000T0000Z-210903T0130Z/
/GRAP1.3.ER.210901T2209Z.210902T0230Z.210902T1930Z.NR/
328 AM EDT Thu Sep 2 2021

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

The Flood Warning continues for
  the Perkiomen Creek At Graterford.
* Until this evening.
* At 10:30 PM EDT Wednesday the stage was 20.6 feet.
* Flood stage is 11.0 feet.
* Major flooding is occurring and major flooding is forecast. This 
  exceeds the flood of record.
* Recent Activity...The maximum river stage in the 24 hours ending 
  at 10:30 PM EDT Wednesday was 20.6 feet.
* Forecast...The river is near crest and expected to fall below 
  flood stage late this afternoon and continue falling to 2.5 feet 
  early Sunday morning.
* Impact...At 8.0 feet, Park Avenue in Schwenksville is flooded. The 
  Perkiomen Trail is flooded in Perkiomen Township at Plank Road and 
  Route 113. Ninth Avenue begins to flood in Collegeville.
* Impact...At 11.0 feet, Graterford Road and Penitentiary Bridge are 
  closed due to flooding.
* Impact...At 12.0 feet, Portions of Central Perkiomen Park in 
  Collegeville are flooded. Flood waters expand onto and to the west 
  of First Avenue in Collegeville.
* Impact...At 13.0 feet, First Avenue in Collegeville becomes 
  impassable.
* Impact...At 14.0 feet, Storm sewers back up in Collegeville and 
  flood Route 29.
* Impact...At 15.0 feet, East Main Street in Collegeville floods.
* Impact...At 16.0 feet, Collegeville businesses on Route 29, 
  between East Ninth Street and East Main Street, begin to take on 
  water.
* Impact...At 18.0 feet, Smaller tributaries are affected by high 
  water from the Perkiomen. Flooding is possible near the Route 113 
  Bridge in Perkiomen Township.
* Impact...At 19.0 feet, The Schwenksville Sewer and Water Plant 
  floods as does Route 73/Haldeman Road.
* Flood History...This crest compares to a previous crest of 19.3 
  feet on 08/05/2020.

&&


               Fld   Observed           Forecasts (2 am EDT)     
Location       Stg   Stg   Day/Time     Fri   Sat   Sun          

Perkiomen Creek
Graterford     11.0  20.6  Wed 10 pm ED 7.4   3.6   2.5          





&&

LAT...LON 4024 7549 4024 7542 4011 7542 4012 7547

$$

Meola

211 
WGUS81 KPHI 021523
FLSPHI

Flood Statement
National Weather Service Mount Holly NJ
1123 AM EDT Thu Sep 2 2021

...The Flood Warning continues for the following rivers in 
Pennsylvania...

  Perkiomen Creek At Graterford affecting Montgomery County.

For the Perkiomen Creek...including Graterford...Moderate flooding 
is forecast.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Motorists should not attempt to drive around barricades or drive 
cars through flooded areas.

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

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


PAC091-030130-
/O.CON.KPHI.FL.W.0038.000000T0000Z-210903T0130Z/
/GRAP1.3.ER.210901T2209Z.210902T0230Z.210903T0100Z.NR/
1123 AM EDT Thu Sep 2 2021

...The Flood Warning remains in effect...

The Flood Warning continues for
  the Perkiomen Creek At Graterford.
* Until this evening.
* Stage is missing.
* Flood stage is 11.0 feet.
* Major flooding is occurring and moderate flooding is forecast. 
  This approaches the flood of record.
* Recent Activity...The maximum river stage in the 24 hours ending 
  at 10:30 PM EDT Wednesday was 20.6 feet.
* Forecast...The river is expected to fall below flood stage late 
  this evening and continue falling to 2.5 feet Sunday morning.
* Impact...At 8.0 feet, Park Avenue in Schwenksville is flooded. The 
  Perkiomen Trail is flooded in Perkiomen Township at Plank Road and 
  Route 113. Ninth Avenue begins to flood in Collegeville.
* Impact...At 11.0 feet, Graterford Road and Penitentiary Bridge are 
  closed due to flooding.
* Impact...At 12.0 feet, Portions of Central Perkiomen Park in 
  Collegeville are flooded. Flood waters expand onto and to the west 
  of First Avenue in Collegeville.
* Impact...At 13.0 feet, First Avenue in Collegeville becomes 
  impassable.
* Impact...At 14.0 feet, Storm sewers back up in Collegeville and 
  flood Route 29.
* Impact...At 15.0 feet, East Main Street in Collegeville floods.
* Impact...At 16.0 feet, Collegeville businesses on Route 29, 
  between East Ninth Street and East Main Street, begin to take on 
  water.
* Impact...At 18.0 feet, Smaller tributaries are affected by high 
  water from the Perkiomen. Flooding is possible near the Route 113 
  Bridge in Perkiomen Township.
* Impact...At 19.0 feet, The Schwensville Sewer and Water Plant 
  floods as does Route 73/Haldeman Road.
* Flood History...This crest compares to a previous crest of 19.3 
  feet on 08/05/2020.

&&


               Fld   Observed           Forecasts (2 pm EDT)     
Location       Stg   Stg   Day/Time     Fri   Sat   Sun          

Perkiomen Creek
Graterford     11.0  20.6  Wed 10 pm ED 6.8   2.7   MSG          





&&

LAT...LON 4024 7549 4024 7542 4011 7542 4012 7547

$$

Kruzdlo

858 
WGUS81 KPHI 021847
FLSPHI

Flood Statement
National Weather Service Mount Holly NJ
247 PM EDT Thu Sep 2 2021

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

  Perkiomen Creek At Graterford affecting Montgomery County.

PAC091-022000-
/O.CAN.KPHI.FL.W.0038.000000T0000Z-210902T1847Z/
/GRAP1.3.ER.210901T2209Z.210902T0230Z.210902T1238Z.NR/
247 PM EDT Thu Sep 2 2021

...The Flood Warning for the Perkiomen Creek At Graterford has been 
cancelled...

The Flood Warning is cancelled for
  the Perkiomen Creek At Graterford.
* At 2:15 PM EDT Thursday the stage was 6.2 feet.
* Flood stage is 11.0 feet.
* Forecast...The river is expected to fall to 2.5 feet early Sunday 
  afternoon.

&&


               Fld   Observed           Forecasts (2 pm EDT)     
Location       Stg   Stg   Day/Time     Fri   Sat   Sun          

Perkiomen Creek
Graterford     11.0  6.2   Thu 2 pm EDT 3.6   2.7   2.5          





&&

LAT...LON 4024 7549 4024 7542 4011 7542 4012 7547

$$

Kruzdlo

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 1, 6:19 AM EDT	Areal Flood Advisory	PHI	Chester, Delaware	116 min
Sep 1, 6:49 AM EDT	Flash Flood Warning	PHI	Chester, Delaware, Philadelphia	86 min
Sep 1, 11:24 AM EDT	Areal Flood Advisory	PHI	Berks, Carbon, Lehigh, Monroe, Northampton	3 hr
Sep 1, 12:07 PM EDT	Flash Flood Warning	PHI	Carbon, Monroe	4 hr
Sep 1, 1:29 PM EDT	Flash Flood Warning	PHI	Berks, Lehigh	6 hr
Sep 1, 2:53 PM EDT	Flash Flood Warning	PHI	Berks, Chester, Delaware, Montgomery	9 hr
Sep 1, 3:55 PM EDT	River Flood Warning	PHI	Montgomery	36 hr
Sep 1, 3:55 PM EDT	River Flood Warning	PHI	Chester, Montgomery, Philadelphia	43 hr
Sep 1, 3:55 PM EDT	River Flood Warning	PHI	Montgomery, Philadelphia	41 hr
Sep 1, 3:55 PM EDT	River Flood Warning	PHI	Philadelphia	39 hr
Sep 1, 3:55 PM EDT	River Flood Warning	PHI	Berks	24 hr
Sep 1, 4:02 PM EDT	River Flood Warning	PHI	Monroe	24 hr
Sep 1, 4:04 PM EDT	Areal Flood Warning	PHI	Carbon, Monroe, Northampton	24 hr
Sep 1, 4:10 PM EDT	River Flood Warning	PHI	Monroe	19 hr
Sep 1, 4:12 PM EDT	Flash Flood Warning	PHI	Berks, Bucks, Lehigh, Montgomery, Northampton	7 hr
Sep 1, 4:12 PM EDT	River Flood Warning	PHI	Lehigh, Northampton	25 hr
Sep 1, 4:12 PM EDT	River Flood Warning	PHI	Lehigh, Northampton	24 hr
Sep 1, 4:12 PM EDT	River Flood Warning	PHI	Carbon	15 hr
Sep 1, 4:13 PM EDT	Tornado Warning	PHI	Chester	32 min
Sep 1, 4:21 PM EDT	River Flood Warning	PHI	Bucks	29 hr
Sep 1, 4:42 PM EDT	Flash Flood Warning EmergencyConsiderable damage threat	PHI	Chester, Delaware, Montgomery	6 hr
Sep 1, 5:07 PM EDT	River Flood Warning	PHI	Chester	17 hr
Sep 1, 5:13 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	47 min
Sep 1, 5:15 PM EDT	Tornado Warning	PHI	Delaware, Montgomery, Philadelphia	30 min
Sep 1, 5:26 PM EDT	Flash Flood Warning	PHI	Bucks, Delaware, Montgomery, Philadelphia	9 hr
Sep 1, 5:34 PM EDT	Tornado Warning	PHI	Bucks, Montgomery, Philadelphia	26 min
Sep 1, 5:42 PM EDT	Flash Flood Warning	PHI	Bucks	10 hr
Sep 1, 5:57 PM EDT	Tornado Warning	PHI	Bucks	33 min
Sep 1, 6:08 PM EDT	Flash Flood Warning	PHI	Monroe, Northampton	6 hr
Sep 1, 6:20 PM EDT	Tornado Warning	PHI	Bucks	40 min
Sep 1, 6:22 PM EDT	Tornado Warning Tornado observed	PHI	Philadelphia	23 min
Sep 1, 6:38 PM EDT	River Flood Warning	PHI	Chester, Delaware	26 hr
Sep 1, 6:42 PM EDT	Tornado Warning	PHI	Bucks, Philadelphia	33 min
Sep 1, 6:59 PM EDT	Severe Thunderstorm Warning	PHI	Bucks	61 min
Sep 1, 7:04 PM EDT	Tornado Warning EmergencyTornado observedCatastrophic damage threat	PHI	Bucks	26 min
Sep 1, 7:05 PM EDT	Flash Flood Warning EmergencyCatastrophic damage threat	PHI	Bucks	8 hr
Sep 1, 7:22 PM EDT	Tornado Warning	PHI	Bucks	11 min
Sep 1, 7:23 PM EDT	Areal Flood Warning	PHI	Berks, Lehigh	14 hr
Sep 1, 7:31 PM EDT	Flash Flood Warning EmergencyCatastrophic damage threat	PHI	Bucks	4 hr
Sep 1, 7:53 PM EDT	River Flood Warning	PHI	Delaware	13 hr

Nearby

River Flood Warnings in Pennsylvania, 2021 Every 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.