Alert archive / Pennsylvania / Flash Flood Warnings in 2020
Flash Flood Warning 60, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 13, 2020, 9:07 AM EDT for Bucks County, Montgomery County, Pennsylvania. It was in force for 3 hr. 6 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
- Aug 13, 2020, 9:07 AM EDT (13:07 UTC)
- Expired
- Aug 13, 2020, 11:41 AM EDT
- In force
- 3 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Flood severity
- None
Counties Bucks County, PA, Montgomery County, PA
The radar
The Philadelphia radar (KDIX), 80 km from the middle of the area, began a volume at 13:09 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 |
|---|---|---|---|
| Aug 13, 9:30 AM EDT | FLASH FLOOD | 1 Wnw Fricks, PA | MILL ROAD CLOSED FROM FLASH FLOODING. TIME BASED ON DISPATCH REPORT. |
| Aug 13, 9:45 AM EDT | FLASH FLOOD | 1 Nw Doylestown, PA | BROAD STREET AND SANDY RIDGE ROAD CLOSED FROM FLASH FLOODING. TIME BASED ON DISPATCH REPORT. |
| Aug 13, 11:00 AM EDT | HEAVY RAIN 2.12 | 1 Ssw Doylestown, PA | PERSONAL WEATHER STATION KPADOYLE21. |
| Aug 13, 11:00 AM EDT | HEAVY RAIN 2.15 | 1 N New Britain, PA | PERSONAL WEATHER STATION KPADOYLE36. |
| Aug 13, 11:00 AM EDT | HEAVY RAIN 2.55 | 3 S Doylestown, PA | PERSONAL WEATHER STATION KPAWARRI11. |
| Aug 13, 11:00 AM EDT | HEAVY RAIN 2.67 | 1 Nnw New Britain, PA | PERSONAL WEATHER STATION KPADOYLE41. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Brookhaven, NY (KOKX), launched 12:00Z, 1.1 hours before the alert went out and 210 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
- 1326 J/kg
- Mixed-layer CIN
- -24 J/kg
- Mixed-layer LCL
- 599 m above ground
- 0-6 km bulk shear
- 15 kt
- 0-1 km storm-relative helicity
- 8 m²/s²
- 0-3 km storm-relative helicity
- 26 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
482
WGUS51 KPHI 131307
FFWPHI
PAC017-091-131700-
/O.NEW.KPHI.FF.W.0060.200813T1307Z-200813T1700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
907 AM EDT Thu Aug 13 2020
The National Weather Service in Mount Holly NJ has issued a
* Flash Flood Warning for...
Central Montgomery County in southeastern Pennsylvania...
Central Bucks County in southeastern Pennsylvania...
* Until 100 PM EDT.
* At 906 AM EDT, Doppler radar and automated gauges indicated
thunderstorms producing heavy rain across the warned area. Up to
two inches of rain have already fallen. Flash flooding is ongoing
or expected to begin shortly.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Radar and automated gauges.
IMPACT...Flooding of small creeks and streams, urban areas,
highways, streets and underpasses as well as other
drainage and low lying areas.
* Some locations that could experience flooding include...
Lansdale, Perkasie, Doylestown, Souderton, Chalfont, Hatfield,
Fricks, Telford, Sellersville, New Britain, Silverdale,
Harleysville, Brittany Farms-Highlands, Kulpsville and
Montgomeryville.
Additional rainfall amounts of 1 to 2 inches are possible in the
warned area.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Protecting yourself from immediate threats to life and safety shall
take priority. Whenever possible, as long as it does not cause
greater harm, all COVID-19 protective action guidance should be
followed.
Turn around...don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 4034 7509 4022 7511 4021 7518 4024 7538
4025 7542 4035 7534 4036 7525
FLASH FLOOD...RADAR AND GAUGE INDICATED
$$
JEO2 follow-up statements
627
WGUS71 KPHI 131356
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
956 AM EDT Thu Aug 13 2020
PAC017-091-131700-
/O.CON.KPHI.FF.W.0060.000000T0000Z-200813T1700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Montgomery PA-Bucks PA-
956 AM EDT Thu Aug 13 2020
...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 100 PM EDT FOR
CENTRAL MONTGOMERY AND CENTRAL BUCKS COUNTIES...
At 953 AM EDT, emergency management reported thunderstorms producing
heavy rain in the area of Doylestown and Buckingham. Multiple roads
have been reported as flooded and closed by local emergency
management. Up to three inches of rain have already fallen based on
radar and gauge estimates. Flash flooding is already occurring and
expected to continue.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Emergency management.
IMPACT...Flooding of small creeks and streams, urban areas,
highways, streets and underpasses as well as other drainage
and low lying areas.
Some locations that could experience flooding include...
Lansdale, Perkasie, Doylestown, Souderton, Chalfont, Hatfield,
Fricks, Telford, Sellersville, New Britain, Silverdale, Harleysville,
Brittany Farms-Highlands, Kulpsville and Montgomeryville.
Additional rainfall amounts of up to 1 inch are possible in the
warned area.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Protecting yourself from immediate threats to life and safety shall
take priority. Whenever possible, as long as it does not cause
greater harm, all COVID-19 protective action guidance should be
followed.
Turn around...don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 4034 7509 4022 7511 4021 7518 4024 7538
4025 7542 4035 7534 4036 7525
FLASH FLOOD...OBSERVED
$$
JEO873
WGUS71 KPHI 131541
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
1141 AM EDT Thu Aug 13 2020
PAC017-091-131551-
/O.CAN.KPHI.FF.W.0060.000000T0000Z-200813T1700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Montgomery PA-Bucks PA-
1141 AM EDT Thu Aug 13 2020
...THE FLASH FLOOD WARNING FOR CENTRAL MONTGOMERY AND CENTRAL BUCKS
COUNTIES IS CANCELLED...
The heavy rain has ended. Flood waters are receding. Flooding is no
longer expected to pose a threat. Please continue to heed any
remaining road closures.
LAT...LON 4034 7509 4022 7511 4021 7518 4024 7538
4025 7542 4035 7534 4036 7525
$$
JEOThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 13, 3:02 AM EDT | Flash Flood Watch | PHI | Bucks, Chester, Delaware, Montgomery, Philadelphia | 17 hr |
| Aug 13, 7:25 AM EDT | Areal Flood Advisory | PHI | Bucks, Montgomery | 2 hr |
| Aug 13, 7:47 AM EDT | Areal Flood Advisory | PHI | Bucks | 118 min |
| Aug 13, 8:37 AM EDT | Flash Flood Warning | PHI | Bucks | 3 hr |
| Aug 13, 3:30 PM EDT | Areal Flood Advisory | PHI | Philadelphia | 3 hr |
| Aug 13, 3:56 PM EDT | Areal Flood Advisory | PHI | Delaware | 2 hr |
| Aug 13, 4:45 PM EDT | Areal Flood Advisory | PHI | Chester, Montgomery | 84 min |
Nearby
Flash Flood Warnings in Pennsylvania, 2020Every flash flood warning in 2020
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.