Alert archive / New Jersey / Flash Flood Warnings in 2020
Flash Flood Warning 41, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 4, 2020, 11:01 AM EDT for 7 counties in New Jersey; Bucks County, Pennsylvania. It was in force for 4 hr. 48 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 4, 2020, 11:01 AM EDT (15:01 UTC)
- Expired
- Aug 4, 2020, 3:00 PM EDT
- In force
- 4 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Flood severity
- None
Counties Burlington County, NJ, Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Ocean County, NJ, Somerset County, NJ, Bucks County, PA
The radar
The Philadelphia radar (KDIX), 67 km from the middle of the area, began a volume at 15:01 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 4, 11:45 AM EDT | HEAVY RAIN 2.24 | 1 Nne Blawenburg, NJ | MESONET STATION SKIN4 0.8 NE BLAWENBURG. |
| Aug 4, 11:45 AM EDT | HEAVY RAIN 2.6 | 2 W Belle Mead, NJ | MESONET STATION NESN4 2.2 W BELLE MEAD. |
| Aug 4, 11:55 AM EDT | HEAVY RAIN 4.04 | 1 Wnw Chalfont, PA | MESONET STATION CW7945 CHALFONT. |
| Aug 4, 12:00 PM EDT | HEAVY RAIN 5.44 | Trumbauersville, PA | NEARBY CREEK AT BARREL RUN TRAIL IS FLOODED. |
| Aug 4, 12:16 PM EDT | HEAVY RAIN 5.8 | Bensalem, PA | |
| Aug 4, 12:30 PM EDT | HEAVY RAIN 2.25 | 3 Se Hopewell, NJ | MESONET STATION EW7502 PRINCETON. |
| Aug 4, 12:30 PM EDT | HEAVY RAIN 2.48 | 1 E Ewing, NJ | MESONET STATION EWGN4 1.3 E EWING. |
| Aug 4, 12:31 PM EDT | HEAVY RAIN 2.17 | 1 Se Upper Makefield Tw, PA | MESONET STATION EW4814 NEWTOWN. |
| Aug 4, 12:31 PM EDT | HEAVY RAIN 2.88 | 1 Ene Skillman, NJ | MESONET STATION EW0478 SKILLMAN. |
| Aug 4, 12:31 PM EDT | HEAVY RAIN 3.43 | 1 Sw Furlong, PA | MESONET STATION DW7780 FURLONG. |
| Aug 4, 12:36 PM EDT | HEAVY RAIN 3.78 | 2 Nne Doylestown, PA | ASOS STATION KDYL DOYLESTOWN. |
| Aug 4, 12:38 PM EDT | HEAVY RAIN 3.35 | 2 Wsw Holland Twp, NJ | MESONET STATION EW7207 MILFORD. |
| Aug 4, 12:40 PM EDT | HEAVY RAIN 2.18 | 4 Ese Sand Brook, NJ | MESONET STATION EW4162 RINGOES. |
| Aug 4, 12:40 PM EDT | HEAVY RAIN 4.07 | 1 Sse Holicong, PA | MESONET STATION CW5234 BUCKINGHAM. |
| Aug 4, 12:40 PM EDT | HEAVY RAIN 6.57 | 1 Nnw Perkasie, PA | MESONET STATION FW3600 SELLERSVILLE. |
| Aug 4, 12:41 PM EDT | HEAVY RAIN 3.35 | 2 N Milford, NJ | MESONET STATION FW7136 MILFORD. |
| Aug 4, 12:41 PM EDT | HEAVY RAIN 4.19 | 1 Nw Kintnersville, PA | MESONET STATION DW7738 KINTNERSVILLE. |
| Aug 4, 12:42 PM EDT | HEAVY RAIN 2.43 | Lambertville, NJ | MESONET STATION FW2229 LAMBERTVILLE. |
| Aug 4, 12:42 PM EDT | HEAVY RAIN 3.09 | 3 Se Sand Brook, NJ | MESONET STATION FW1999 RINGOES. |
| Aug 4, 12:43 PM EDT | HEAVY RAIN 3.88 | 1 Sw Swinesburg, NJ | MESONET STATION FW7173 BLOOMSBURY. |
| Aug 4, 12:44 PM EDT | HEAVY RAIN 5.78 | 2 Wsw Haycock Twp, PA | MESONET STATION FW2625 QUAKERTOWN. |
| Aug 4, 12:45 PM EDT | HEAVY RAIN 4.12 | 1 Ene Mumbauersville, PA | MESONET STATION CW6963 QUAKERTOWN. |
| Aug 4, 12:49 PM EDT | HEAVY RAIN 2.45 | 2 Wsw Jamison, PA | MESONET STATION CW1708 WARRINGTON. |
| Aug 4, 12:54 PM EDT | HEAVY RAIN 2.07 | 1 Ene Holland Twp, NJ | MESONET STATION MLFHT MILFORD NW. |
| Aug 4, 12:55 PM EDT | HEAVY RAIN 2.16 | 1 Se Newtown, PA | MESONET STATION NWTOW NEWTOWN (GEORGE). |
| Aug 4, 12:55 PM EDT | HEAVY RAIN 2.89 | 1 Wsw Pennington, NJ | MESONET STATION PNNNG PENNINGTON. |
| Aug 4, 1:00 PM EDT | FLASH FLOOD | 3 Wsw Cloverhill, NJ | THE GAUGE ON THE NESHANIC RIVER IN REAVILLE REACHED FLOOD STAGE AT 100 PM AND CRESTED AT 9.31 FEET AT 345 PM ON AUGUST 4. |
| Aug 4, 1:15 PM EDT | FLASH FLOOD | 1 Sw Wrightstown Twp, PA | THE GAUGE ON NESHAMINY CREEK AT PENNS PARK REACHED FLOOD STAGE AT 115 PM AND CRESTED AT 17.12 FEET (MODERATE FLOODING) AT 830 PM ON AUGUST 4. |
| Aug 4, 2:00 PM EDT | HEAVY RAIN 2.1 | 2 Ne Solebury Twp, PA | MESONET STATION STKN4 STOCKTON. |
| Aug 4, 2:00 PM EDT | HEAVY RAIN 2.84 | New Lisbon, NJ | MESONET STATION NLBN4 NEW LISBON. |
| Aug 4, 2:00 PM EDT | HEAVY RAIN 3.77 | 1 E Ewing, NJ | MESONET STATION EWGN4 1.3 E EWING. |
| Aug 4, 2:03 PM EDT | FLOOD | 1 E East Rockhill Twp, PA | VIDEO OF PERKIOMEN CREEK WELL OUT ITS BANKS AND UP TO A HOME UPSTREAM OF PERKASIE. |
| Aug 4, 2:28 PM EDT | HEAVY RAIN 4.13 | 1 Sse Holicong, PA | MESONET STATION CW5234 BUCKINGHAM. |
| Aug 4, 2:30 PM EDT | HEAVY RAIN 4.3 | 1 Ene Mumbauersville, PA | MESONET STATION CW6963 QUAKERTOWN. |
| Aug 4, 2:53 PM EDT | HEAVY RAIN 2.15 | 1 Nw Ewing, NJ | ASOS STATION KTTN TRENTON. |
| Aug 4, 2:54 PM EDT | HEAVY RAIN 4.34 | 2 Nne Doylestown, PA | ASOS STATION KDYL DOYLESTOWN. |
| Aug 4, 2:58 PM EDT | HEAVY RAIN 3.25 | 3 Se Sand Brook, NJ | MESONET STATION FW1999 RINGOES. |
| Aug 4, 3:00 PM EDT | HEAVY RAIN 2.23 | 1 Se Upper Makefield Tw, PA | MESONET STATION EW4814 NEWTOWN. |
| Aug 4, 3:00 PM EDT | HEAVY RAIN 2.94 | 1 Ene Skillman, NJ | MESONET STATION EW0478 SKILLMAN. |
| Aug 4, 3:00 PM EDT | COASTAL FLOOD | 1 Ssw Bristol, PA | TIDAL GAUGE ON THE DELAWARE RIVER AT BURLINGTON CRESTED IN MODERATE FLOOD AT 10.6 FT THIS AFTERNOON. |
| Aug 4, 3:01 PM EDT | HEAVY RAIN 2 | 2 W Princeton, NJ | MESONET STATION FW0303 PRINCETON. |
| Aug 4, 3:01 PM EDT | HEAVY RAIN 2.06 | 1 Nw Newtown Twp, PA | MESONET STATION FW0776 NEWTOWN. |
| Aug 4, 3:01 PM EDT | HEAVY RAIN 3.47 | 1 Sw Furlong, PA | MESONET STATION DW7780 FURLONG. |
| Aug 4, 3:02 PM EDT | HEAVY RAIN 2.29 | 3 Se Hopewell, NJ | MESONET STATION EW7502 PRINCETON. |
| Aug 4, 3:05 PM EDT | HEAVY RAIN 7.43 | 1 Nnw Perkasie, PA | MESONET STATION FW3600 SELLERSVILLE. |
| Aug 4, 3:10 PM EDT | HEAVY RAIN 3.51 | 2 Wsw Holland Twp, NJ | MESONET STATION EW7207 MILFORD. |
| Aug 4, 3:10 PM EDT | HEAVY RAIN 3.52 | 2 N Milford, NJ | MESONET STATION FW7136 MILFORD. |
| Aug 4, 3:10 PM EDT | HEAVY RAIN 4.18 | 1 Sw Swinesburg, NJ | MESONET STATION FW7173 BLOOMSBURY. |
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, 3.0 hours before the alert went out and 192 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
- 1593 J/kg
- Mixed-layer CIN
- -3 J/kg
- Mixed-layer LCL
- 570 m above ground
- 0-6 km bulk shear
- 53 kt
- 0-1 km storm-relative helicity
- 150 m²/s²
- 0-3 km storm-relative helicity
- 245 m²/s²
- Significant tornado parameter
- 1.5
- Supercell composite
- 7.4
The text
As transmitted.
909
WGUS51 KPHI 041501
FFWPHI
NJC005-019-021-023-025-029-035-PAC017-041900-
/O.NEW.KPHI.FF.W.0041.200804T1501Z-200804T1900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
1101 AM EDT Tue Aug 4 2020
The National Weather Service in Mount Holly NJ has issued a
* Flash Flood Warning for...
Northwestern Ocean County in southern New Jersey...
Southern Hunterdon County in northwestern New Jersey...
Mercer County in central New Jersey...
Northeastern Burlington County in southern New Jersey...
Southwestern Somerset County in northern New Jersey...
Southwestern Monmouth County in central New Jersey...
Southwestern Middlesex County in northern New Jersey...
Bucks County in southeastern Pennsylvania...
* Until 300 PM EDT.
* At 1100 AM EDT, Doppler radar indicated thunderstorms producing
heavy rain just south of the warned area. Two to three inches of
rain have been falling in about one hour with these storms. The
heavy rain was moving north and will move into the warned area
shortly. Flash flooding will likely occur as a result.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Radar indicated.
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...
Trenton, Bensalem, Manalapan, Ewing, Princeton, Florence,
Burlington, Bristol, Mount Holly, Quakertown, Perkasie, Doylestown,
Byram, Hatboro, Souderton, Bedminster, Hightstown, Flemington,
Chalfont and Tinicum.
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.
A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.
&&
LAT...LON 3987 7458 4010 7497 4012 7497 4017 7508
4042 7548 4047 7543 4054 7534 4061 7521
4059 7518 4063 7515 4067 7506 4021 7427
FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-2 INCHES IN 1 HOUR
$$
Kruzdlo1 follow-up statement
265
WGUS71 KPHI 041832
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
232 PM EDT Tue Aug 4 2020
NJC005-025-029-041839-
/O.CAN.KPHI.FF.W.0041.000000T0000Z-200804T1900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Ocean NJ-Burlington NJ-Monmouth NJ-
232 PM EDT Tue Aug 4 2020
...THE FLASH FLOOD WARNING FOR NORTHWESTERN OCEAN...NORTHEASTERN
BURLINGTON AND SOUTHWESTERN MONMOUTH COUNTIES IS CANCELLED...
Flooding is no longer expected to pose a threat. Please continue to
heed any remaining road closures.
LAT...LON 4007 7491 4009 7496 4012 7497 4020 7513
4042 7548 4056 7531 4060 7521 4059 7518
4063 7515 4067 7506 4032 7446
$$
NJC019-021-023-035-PAC017-041900-
/O.CON.KPHI.FF.W.0041.000000T0000Z-200804T1900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hunterdon NJ-Mercer NJ-Somerset NJ-Middlesex NJ-Bucks PA-
232 PM EDT Tue Aug 4 2020
...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 300 PM EDT FOR
SOUTHERN HUNTERDON...MERCER...SOUTHWESTERN SOMERSET...SOUTHWESTERN
MIDDLESEX AND BUCKS COUNTIES...
At 229 PM EDT, gauge reports indicated flooding occuring across the
warned area. Up to 7 inches of rain fell earlier today. Any
additional rain should be light. However, it will take time for the
runoff to recede. Flash flooding is already occurring.
HAZARD...Flash flooding caused by heavy rain.
SOURCE...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...
Trenton, Bensalem, Ewing, Princeton, Bristol, Quakertown, Perkasie,
Doylestown, Byram, Hatboro, Souderton, Bedminster, Flemington,
Chalfont, Tinicum, Cranbury, Pennington, New Hope, Yardley and
Newtown.
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.
A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.
&&
LAT...LON 4007 7491 4009 7496 4012 7497 4020 7513
4042 7548 4056 7531 4060 7521 4059 7518
4063 7515 4067 7506 4032 7446
FLASH FLOOD...GAUGE INDICATED
$$
SFJThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 3, 8:07 PM EDT | Special Weather Statement | PHI | Hunterdon, Somerset, Warren | 23 min |
| Aug 3, 8:26 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Middlesex, Morris, Somerset | 34 min |
| Aug 3, 9:02 PM EDT | Special Weather Statement | PHI | Morris | 28 min |
| Aug 4, 5:17 AM EDT | Areal Flood Advisory | PHI | Burlington, Camden, Gloucester, Hunterdon, Mercer, Salem and 1 more | 4 hr |
| Aug 4, 5:55 AM EDT | Special Marine Warning | PHI | 21 min | |
| Aug 4, 7:28 AM EDT | Flash Flood Warning | PHI | Gloucester, Salem | 3 hr |
| Aug 4, 8:38 AM EDT | Special Marine Warning | PHI | 52 min | |
| Aug 4, 9:16 AM EDT | Tornado Warning | PHI | Cumberland | 18 min |
| Aug 4, 9:28 AM EDT | Special Marine Warning | PHI | 32 min | |
| Aug 4, 9:31 AM EDT | Special Marine Warning | PHI | 59 min | |
| Aug 4, 9:42 AM EDT | Tornado Warning | PHI | Atlantic, Cape May | 19 min |
| Aug 4, 10:02 AM EDT | Flash Flood Warning | PHI | Gloucester, Salem | 4 hr |
| Aug 4, 10:15 AM EDT | Tornado Warning | PHI | Atlantic, Burlington, Ocean | 14 min |
| Aug 4, 10:20 AM EDT | Flash Flood Warning | PHI | Burlington, Camden, Gloucester | 4 hr |
| Aug 4, 11:00 AM EDT | Tornado Warning | PHI | Monmouth, Ocean | 11 min |
| Aug 4, 11:13 AM EDT | Areal Flood Advisory | PHI | Sussex, Warren | 4 hr |
| Aug 4, 11:43 AM EDT | Flash Flood Warning | PHI | Warren | 4 hr |
| Aug 4, 11:59 AM EDT | Areal Flood Advisory | PHI | Hunterdon, Middlesex, Monmouth, Morris, Somerset | 4 hr |
| Aug 4, 2:33 PM EDT | River Flood Warning | PHI | Hunterdon, Somerset | 5 hr |
| Aug 4, 2:47 PM EDT | Areal Flood Warning | PHI | Hunterdon, Mercer, Middlesex, Somerset, Warren | 9 hr |
| Aug 4, 3:42 PM EDT | Areal Flood Warning | PHI | Warren | 4 hr |
| Aug 4, 4:37 PM EDT | Areal Flood Warning | PHI | Cumberland, Salem | 10 hr |
| Aug 4, 5:04 PM EDT | Small Craft Advisory | PHI | 14 hr | |
| Aug 4, 5:30 PM EDT | Coastal Flood Statement | PHI | Ocean | 103 min |
| Aug 4, 7:23 AM EDT | Tornado Warning | PHI | Chester, Delaware, Montgomery, Philadelphia | 20 min |
| Aug 4, 8:11 AM EDT | Flash Flood Warning | PHI | Bucks, Lehigh, Montgomery, Northampton | 4 hr |
| Aug 4, 8:19 AM EDT | River Flood Warning | PHI | Delaware | 15 hr |
| Aug 4, 8:19 AM EDT | Tornado Warning | PHI | Bucks | 26 min |
| Aug 4, 9:23 AM EDT | Tornado Warning | PHI | Chester | 22 min |
| Aug 4, 9:29 AM EDT | Tornado Warning | PHI | Monroe, Northampton | 31 min |
| Aug 4, 9:38 AM EDT | Flash Flood Warning | PHI | Monroe, Northampton | 4 hr |
| Aug 4, 9:58 AM EDT | Tornado Warning | PHI | Monroe | 16 min |
| Aug 4, 10:51 AM EDT | Tornado Warning | PHI | Montgomery | 24 min |
| Aug 4, 12:06 PM EDT | River Flood Warning | PHI | Chester | 11 hr |
| Aug 4, 12:37 PM EDT | River Flood Warning | PHI | Montgomery | 14 hr |
| Aug 4, 12:48 PM EDT | River Flood Warning | PHI | Chester, Delaware | 24 hr |
| Aug 4, 1:01 PM EDT | River Flood Warning | PHI | Bucks | 18 hr |
| Aug 4, 1:12 PM EDT | River Flood Warning | PHI | Berks | 10 hr |
| Aug 4, 1:12 PM EDT | River Flood Warning | PHI | Montgomery | 26 hr |
| Aug 4, 1:12 PM EDT | River Flood Warning | PHI | Chester, Montgomery, Philadelphia | 43 hr |
| Aug 4, 1:12 PM EDT | River Flood Warning | PHI | Montgomery, Philadelphia | 35 hr |
| Aug 4, 1:59 PM EDT | Areal Flood Warning | PHI | Chester, Delaware | 9 hr |
| Aug 4, 2:09 PM EDT | Areal Flood Warning | PHI | Berks, Chester, Delaware, Montgomery, Philadelphia | 15 hr |
| Aug 4, 2:23 PM EDT | River Flood Warning | PHI | Lehigh | 16 hr |
| Aug 4, 4:39 PM EDT | River Flood Warning | PHI | Monroe | 6 hr |
| Aug 4, 7:29 PM EDT | Areal Flood Warning | PHI | Lehigh, Northampton | 12 hr |
Nearby
Flash Flood Warnings in New Jersey, 2020Flash 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.