Alert archive / New Jersey / Flash Flood Watches in 2020

Flash Flood Watch 1, NWS Philadelphia/Mount Holly

June 5, 20204 states

NWS Philadelphia/Mount Holly issued this flash flood watch at Jun 5, 2020, 9:47 AM EDT for 4 states. It took effect at Jun 5, 2020, 2:00 PM EDT. It was in force for 7 hr.

The area

The counties it named.

The facts

Issued
Jun 5, 2020, 9:47 AM EDT (13:47 UTC)
In effect from
Jun 5, 2020, 2:00 PM EDT
Expired
Jun 5, 2020, 9:20 PM EDT
In force
7 hr
Issued by
NWS Philadelphia/Mount Holly
Flood severity
None
All 24 counties

New Castle County, DE, Cecil County, MD, Kent County, MD, Atlantic County, NJ, Burlington County, NJ, Camden County, NJ, Cumberland County, NJ, Gloucester County, NJ, Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Ocean County, NJ, Salem County, NJ, Somerset County, NJ, Warren County, NJ, Berks County, PA, Bucks County, PA, Chester County, PA, Delaware County, PA, Lehigh County, PA, Montgomery County, PA, Northampton County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 63 km from the middle of the area, began a volume at 13:50 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 nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 1.8 hours before the alert went out and 212 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.

Skew-T log-pSkew-T log-p diagram, Brookhaven, NY at 12:00Z on 2020-06-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 34 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 12:00Z on 2020-06-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 139 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
34 J/kg
Mixed-layer CIN
-275 J/kg
Mixed-layer LCL
685 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
139 m²/s²
0-3 km storm-relative helicity
150 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

152 
WGUS61 KPHI 051347
FFAPHI

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Mount Holly NJ
947 AM EDT Fri Jun 5 2020

DEZ001-MDZ008-012-NJZ007-009-010-012>022-025>027-PAZ060>062-070-
071-101>106-052215-
/O.NEW.KPHI.FF.A.0001.200605T1800Z-200606T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle-Cecil-Kent MD-Warren-Hunterdon-Somerset-Middlesex-
Western Monmouth-Eastern Monmouth-Mercer-Salem-Gloucester-Camden-
Northwestern Burlington-Ocean-Cumberland-Atlantic-
Coastal Atlantic-Coastal Ocean-Southeastern Burlington-Berks-
Lehigh-Northampton-Delaware-Philadelphia-Western Chester-
Eastern Chester-Western Montgomery-Eastern Montgomery-Upper Bucks-
Lower Bucks-
Including the cities of Wilmington, Elkton, Chestertown, 
Washington, Flemington, Somerville, New Brunswick, Freehold, 
Sandy Hook, Trenton, Pennsville, Glassboro, Camden, Cherry Hill, 
Moorestown, Mount Holly, Jackson, Millville, Hammonton, 
Atlantic City, Long Beach Island, Wharton State Forest, Reading, 
Allentown, Bethlehem, Easton, Media, Philadelphia, Honey Brook, 
Oxford, West Chester, Kennett Square, Collegeville, Pottstown, 
Norristown, Lansdale, Chalfont, Perkasie, Morrisville, 
and Doylestown
947 AM EDT Fri Jun 5 2020

...FLASH FLOOD WATCH IN EFFECT FROM 2 PM EDT THIS AFTERNOON
THROUGH THIS EVENING...

The National Weather Service in Mount Holly has issued a

* Flash Flood Watch for portions of northern Delaware, northeast
  Maryland, New Jersey, and Pennsylvania, including the following
  areas, in northern Delaware, New Castle. In northeast Maryland,
  Cecil and Kent. In New Jersey, Atlantic, Burlington, Camden, 
  Cumberland, Gloucester, Hunterdon, Mercer, Middlesex, Monmouth, 
  Ocean, Salem, Somerset, and Warren. In Pennsylvania, Berks, 
  Bucks, Chester, Delaware, Lehigh, Montgomery, Northampton, and 
  Philadelphia. 

* From 2 PM EDT this afternoon through this evening

* Thunderstorms are expected to develop this afternoon in
  southeastern Pennsylvania into northern and central New Jersey.
  The strongest storms will be capable of producing locally heavy
  rainfall amounts of 1.5 to 2.5 inches in as little as an hour.
  Additionally, storm motions today will be slow, and storms may
  train over the same areas. As a result, instances of flash
  flooding are possible in the watch area.

* In the areas of heaviest rainfall, flash flooding of small
  creeks and streams, poor-drainage areas, and urban areas may 
  occur between mid afternoon and late this evening.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that there is the potential for flash
flooding which can be life-threatening. Heavy rain is expected to
occur over a short period of time. Rapidly rising flood waters
may quickly inundate roadways and areas of poor drainage. Streams
and creeks could leave their banks, flooding nearby properties.

Please monitor the forecast, especially if you live in a location
that is prone to flooding. Be prepared to take action if a flash 
flood warning is issued for your area.

&&

$$

CMS
2 follow-up statements
730 
WGUS61 KPHI 052158
FFAPHI

Flood Watch
National Weather Service Mount Holly NJ
558 PM EDT Fri Jun 5 2020

DEZ001-MDZ008-012-NJZ007-009-010-012>022-025>027-PAZ060>062-070-
071-101>106-060400-
/O.CON.KPHI.FF.A.0001.000000T0000Z-200606T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle-Cecil-Kent MD-Warren-Hunterdon-Somerset-Middlesex-
Western Monmouth-Eastern Monmouth-Mercer-Salem-Gloucester-Camden-
Northwestern Burlington-Ocean-Cumberland-Atlantic-
Coastal Atlantic-Coastal Ocean-Southeastern Burlington-Berks-
Lehigh-Northampton-Delaware-Philadelphia-Western Chester-
Eastern Chester-Western Montgomery-Eastern Montgomery-Upper Bucks-
Lower Bucks-
Including the cities of Wilmington, Elkton, Chestertown, 
Washington, Flemington, Somerville, New Brunswick, Freehold, 
Sandy Hook, Trenton, Pennsville, Glassboro, Camden, Cherry Hill, 
Moorestown, Mount Holly, Jackson, Millville, Hammonton, 
Atlantic City, Long Beach Island, Wharton State Forest, Reading, 
Allentown, Bethlehem, Easton, Media, Philadelphia, Honey Brook, 
Oxford, West Chester, Kennett Square, Collegeville, Pottstown, 
Norristown, Lansdale, Chalfont, Perkasie, Morrisville, 
and Doylestown
558 PM EDT Fri Jun 5 2020

...FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL MIDNIGHT EDT
TONIGHT...

The Flash Flood Watch continues for

* Portions of northern Delaware, northeast Maryland, New Jersey,
  and southeast Pennsylvania. 

* Until midnight EDT tonight

* Thunderstorms continue across the watch area this evening. The 
  strongest storms will be capable of producing locally heavy 
  rainfall amounts of 1.5 to 2.5 inches in as little as an hour. 
  Additionally, storm motions today will be slow, and storms may 
  train over the same areas. As a result, instances of flash 
  flooding are possible in the watch area. 

* In the areas of heaviest rainfall, flash flooding of small
  creeks and streams, poor-drainage areas, and urban areas may
  occur through late evening. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that there is the potential for flash
flooding which can be life-threatening. Heavy rain is expected to
occur over a short period of time. Rapidly rising flood waters
may quickly inundate roadways and areas of poor drainage. Streams
and creeks could leave their banks, flooding nearby properties.

Please monitor the forecast, especially if you live in a location
that is prone to flooding. Be prepared to take action if a flash
flood warning is issued for your area.

&&

$$

Meola
554 
WGUS61 KPHI 060120
FFAPHI

Flood Watch
National Weather Service Mount Holly NJ
920 PM EDT Fri Jun 5 2020

DEZ001-MDZ008-012-NJZ007-009-010-012>022-025>027-PAZ060>062-070-
071-101>106-060230-
/O.CAN.KPHI.FF.A.0001.000000T0000Z-200606T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle-Cecil-Kent MD-Warren-Hunterdon-Somerset-Middlesex-
Western Monmouth-Eastern Monmouth-Mercer-Salem-Gloucester-Camden-
Northwestern Burlington-Ocean-Cumberland-Atlantic-
Coastal Atlantic-Coastal Ocean-Southeastern Burlington-Berks-
Lehigh-Northampton-Delaware-Philadelphia-Western Chester-
Eastern Chester-Western Montgomery-Eastern Montgomery-Upper Bucks-
Lower Bucks-
Including the cities of Wilmington, Elkton, Chestertown, 
Washington, Flemington, Somerville, New Brunswick, Freehold, 
Sandy Hook, Trenton, Pennsville, Glassboro, Camden, Cherry Hill, 
Moorestown, Mount Holly, Jackson, Millville, Hammonton, 
Atlantic City, Long Beach Island, Wharton State Forest, Reading, 
Allentown, Bethlehem, Easton, Media, Philadelphia, Honey Brook, 
Oxford, West Chester, Kennett Square, Collegeville, Pottstown, 
Norristown, Lansdale, Chalfont, Perkasie, Morrisville, 
and Doylestown
920 PM EDT Fri Jun 5 2020

...FLASH FLOOD WATCH IS CANCELLED...

The Flash Flood Watch for portions of northern Delaware,
northeast Maryland, New Jersey, and Pennsylvania has been
cancelled. The threat of flash flooding due to heavy rain from 
thunderstorms has ended. Areas of light to moderate rain may
continue to move through the region overnight. 

$$

Meola

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 4, 9:15 PM EDTSpecial Weather StatementPHICecil, Kent, Queen Anne's, Talbot45 min
Jun 4, 9:30 PM EDTSevere Thunderstorm WarningPHICecil, Kent, Queen Anne's28 min
Jun 4, 9:54 PM EDTSpecial Weather StatementPHICaroline, Cecil, Talbot36 min
Jun 4, 10:12 PM EDTSevere Thunderstorm WarningPHICecil, Kent33 min
Jun 4, 10:07 PM EDTSpecial Marine WarningPHI53 min
Jun 4, 10:31 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden, Gloucester46 min
Jun 4, 10:32 PM EDTSevere Thunderstorm WarningPHIAtlantic, Camden, Cumberland, Gloucester, Salem42 min
Jun 4, 10:52 PM EDTSpecial Marine WarningPHI38 min
Jun 4, 10:59 PM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 1 more34 min
Jun 5, 12:06 AM EDTSpecial Marine WarningPHI54 min
Jun 5, 3:24 PM EDTSpecial Weather StatementPHIMercer, Middlesex, Monmouth36 min
Jun 5, 3:57 PM EDTSpecial Weather StatementPHIMercer, Middlesex, Monmouth33 min
Jun 5, 4:36 PM EDTSpecial Weather StatementPHIMonmouth24 min
Jun 5, 4:55 PM EDTSpecial Weather StatementPHIMonmouth, Ocean50 min
Jun 5, 5:01 PM EDTAreal Flood AdvisoryPHIBurlington, Mercer, Middlesex, Monmouth, Ocean, Somerset4 hr
Jun 5, 5:19 PM EDTAreal Flood AdvisoryPHIBurlington, Camden, Gloucester, Ocean, Salem4 hr
Jun 5, 5:27 PM EDTFlash Flood WarningPHIMonmouth, Ocean3 hr
Jun 4, 10:05 PM EDTSpecial Weather StatementPHIChester, Delaware, Montgomery, Philadelphia40 min
Jun 4, 10:46 PM EDTAreal Flood AdvisoryPHIBerks, Carbon, Lehigh, Monroe, Northampton119 min
Jun 5, 3:15 PM EDTSpecial Weather StatementPHIBucks, Montgomery30 min
Jun 5, 3:48 PM EDTAreal Flood AdvisoryPHIBucks, Chester, Delaware, Montgomery, Philadelphia3 hr
Jun 5, 4:14 PM EDTSpecial Weather StatementPHIBerks16 min

Nearby

Flash Flood Watches in New Jersey, 2020Flash Flood Watches in Pennsylvania, 2020Flash Flood Watches in Maryland, 2020Every flash flood watch 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.