Alert archive / New Jersey / Flash Flood Watches in 2018

Flash Flood Watch 2, NWS Philadelphia/Mount Holly

May 15, 20184 states

NWS Philadelphia/Mount Holly issued this flash flood watch at May 15, 2018, 3:40 AM EDT for 4 states. It took effect at May 15, 2018, 4:00 PM EDT. It was in force for 8 hr.

The area

The counties it named.

The facts

Issued
May 15, 2018, 3:40 AM EDT (07:40 UTC)
In effect from
May 15, 2018, 4:00 PM EDT
Expired
May 16, 2018, 12:20 AM EDT
In force
8 hr
Issued by
NWS Philadelphia/Mount Holly
Flood severity
None
All 28 counties

Kent County, DE, New Castle County, DE, Sussex County, DE, Caroline County, MD, Cecil County, MD, Kent County, MD, Queen Anne's County, MD, Talbot County, MD, Atlantic County, NJ, Burlington County, NJ, Camden County, NJ, Cape May 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, Berks County, PA, Bucks County, PA, Chester County, PA, Delaware County, PA, Lehigh County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 74 km from the middle of the area, began a volume at 07:44 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

Wallops Is Stn, VA (KWAL), launched 00:00Z, 7.7 hours before the alert went out and 203 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, Wallops Is Stn, VA at 00:00Z on 2018-05-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2 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, Wallops Is Stn, VA at 00:00Z on 2018-05-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 82 square meters per square second.1939Sfc1 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
2 J/kg
Mixed-layer CIN
-306 J/kg
Mixed-layer LCL
1134 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
82 m²/s²
0-3 km storm-relative helicity
104 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

048 
WGUS61 KPHI 150740
FFAPHI

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Mount Holly NJ
340 AM EDT Tue May 15 2018

DEZ001-002-MDZ008-012-015-NJZ009-010-012>027-PAZ060-061-070-071-
101>106-151545-
/O.NEW.KPHI.FF.A.0002.180515T2000Z-180516T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle-Kent-Cecil-Kent MD-Queen Annes-Hunterdon-Somerset-
Middlesex-Western Monmouth-Eastern Monmouth-Mercer-Salem-
Gloucester-Camden-Northwestern Burlington-Ocean-Cumberland-
Atlantic-Cape May-Atlantic Coastal Cape May-Coastal Atlantic-
Coastal Ocean-Southeastern Burlington-Berks-Lehigh-Delaware-
Philadelphia-Western Chester-Eastern Chester-Western Montgomery-
Eastern Montgomery-Upper Bucks-Lower Bucks-
Including the cities of Wilmington, Dover, Elkton, Chestertown, 
Centreville, Flemington, Somerville, New Brunswick, Freehold, 
Sandy Hook, Trenton, Pennsville, Glassboro, Camden, Cherry Hill, 
Moorestown, Mount Holly, Jackson, Millville, Hammonton, 
Cape May Court House, Ocean City, Atlantic City, 
Long Beach Island, Wharton State Forest, Reading, Allentown, 
Media, Philadelphia, Honey Brook, Oxford, West Chester, 
Kennett Square, Collegeville, Pottstown, Norristown, Lansdale, 
Chalfont, Perkasie, Morrisville, and Doylestown
340 AM EDT Tue May 15 2018

...FLASH FLOOD WATCH IN EFFECT FROM THIS AFTERNOON THROUGH LATE
TONIGHT...

The National Weather Service in Mount Holly has issued a

* Flash Flood Watch for portions of Delaware, northeast 
  Maryland, New Jersey, and Pennsylvania, including the 
  following areas, in Delaware, Kent and New Castle. In 
  northeast Maryland, Cecil, Kent MD, and Queen Annes. In New 
  Jersey, Atlantic, Atlantic Coastal Cape May, Camden, Cape May, 
  Coastal Atlantic, Coastal Ocean, Cumberland, Eastern Monmouth, 
  Gloucester, Hunterdon, Mercer, Middlesex, Northwestern 
  Burlington, Ocean, Salem, Somerset, Southeastern Burlington, 
  and Western Monmouth. In Pennsylvania, Berks, Delaware, 
  Eastern Chester, Eastern Montgomery, Lehigh, Lower Bucks, 
  Philadelphia, Upper Bucks, Western Chester, and Western 
  Montgomery. 

* From 4 PM EDT today to 2 AM EDT Wednesday.

* A line of intense thunderstorms is expected to move into the
  region from the northwest late this afternoon and this evening.
  There are indications that storms may repeatedly move over the
  same areas, especially during the evening hours. Localized
  rainfall of one to three inches is likely where this occurs.
  Combined with the rainfall received this past weekend, this may
  lead to a few instances of flash flooding.

* The areas of greatest risk are poor-drainage and urban
  locations, where rapid runoff may cause localized flash
  flooding. Quickly responding creeks and streams may also
  experience flooding in areas receiving the heaviest rainfall.
  The storms are expected to move through the area during or just
  after the evening commute. Motorists should be prepared for
  torrential downpours and potential flooding as the storms move
  through.

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
5 follow-up statements
338 
WGUS61 KPHI 151505
FFAPHI

Flood Watch
National Weather Service Mount Holly NJ
1105 AM EDT Tue May 15 2018


DEZ001-002-MDZ008-012-015-NJZ009-010-012>027-PAZ060-061-070-071-
101>106-160600-
/O.CON.KPHI.FF.A.0002.180515T2000Z-180516T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle-Kent-Cecil-Kent MD-Queen Annes-Hunterdon-Somerset-
Middlesex-Western Monmouth-Eastern Monmouth-Mercer-Salem-
Gloucester-Camden-Northwestern Burlington-Ocean-Cumberland-
Atlantic-Cape May-Atlantic Coastal Cape May-Coastal Atlantic-
Coastal Ocean-Southeastern Burlington-Berks-Lehigh-Delaware-
Philadelphia-Western Chester-Eastern Chester-Western Montgomery-
Eastern Montgomery-Upper Bucks-Lower Bucks-
Including the cities of Wilmington, Dover, Elkton, Chestertown, 
Centreville, Flemington, Somerville, New Brunswick, Freehold, 
Sandy Hook, Trenton, Pennsville, Glassboro, Camden, Cherry Hill, 
Moorestown, Mount Holly, Jackson, Millville, Hammonton, 
Cape May Court House, Ocean City, Atlantic City, 
Long Beach Island, Wharton State Forest, Reading, Allentown, 
Media, Philadelphia, Honey Brook, Oxford, West Chester, 
Kennett Square, Collegeville, Pottstown, Norristown, Lansdale, 
Chalfont, Perkasie, Morrisville, and Doylestown
1105 AM EDT Tue May 15 2018

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM 4 PM EDT THIS
AFTERNOON THROUGH LATE TONIGHT...

The Flash Flood Watch continues for

* Portions of Delaware, northeast Maryland, New Jersey, and 
  Pennsylvania, including the following areas, in Delaware, Kent 
  and New Castle. In northeast Maryland, Cecil, Kent MD, and 
  Queen Annes. In New Jersey, Atlantic, Atlantic Coastal Cape 
  May, Camden, Cape May, Coastal Atlantic, Coastal Ocean, 
  Cumberland, Eastern Monmouth, Gloucester, Hunterdon, Mercer, 
  Middlesex, Northwestern Burlington, Ocean, Salem, Somerset, 
  Southeastern Burlington, and Western Monmouth. In 
  Pennsylvania, Berks, Delaware, Eastern Chester, Eastern 
  Montgomery, Lehigh, Lower Bucks, Philadelphia, Upper Bucks, 
  Western Chester, and Western Montgomery. 

* From 4 PM EDT this afternoon through late tonight

* A line of intense thunderstorms is expected to move into the
  region from the northwest late this afternoon and this evening.
  There are indications that storms may repeatedly move over the
  same areas, especially later in the evening. Localized rainfall
  of one to three inches is likely where this occurs. Combined 
  with the rainfall received this past weekend, this may lead to a
  few instances of flash flooding. 

* The areas of greatest risk are poor-drainage and urban 
  locations, where rapid runoff may cause localized flash 
  flooding. Quickly responding creeks and streams may also 
  experience flooding in areas receiving the heaviest rainfall. 
  The storms are expected to move through the area during or 
  just after the evening commute. Motorists should be prepared 
  for torrential downpours and potential flooding as the storms 
  move through. 

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.

&&

$$
761 
WGUS61 KPHI 151920
FFAPHI

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Mount Holly NJ
320 PM EDT Tue May 15 2018

DEZ003-004-MDZ019-020-160330-
/O.EXA.KPHI.FF.A.0002.180515T2000Z-180516T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Inland Sussex-Delaware Beaches-Talbot-Caroline-
Including the cities of Georgetown, Rehoboth Beach, Easton, 
and Denton
320 PM EDT Tue May 15 2018

...FLASH FLOOD WATCH IN EFFECT UNTIL 2 AM EDT WEDNESDAY...

The National Weather Service in Mount Holly has expanded the

* Flash Flood Watch to include portions of southern Delaware and 
  northeast Maryland, including the following areas, in southern 
  Delaware, Delaware Beaches and Inland Sussex. In northeast 
  Maryland, Caroline and Talbot. 

* Until 2 AM EDT Wednesday

* A line of intense thunderstorms is on track to move into the
  region from the northwest between 5 PM and 9 PM, continuing 
  into this evening. There are indications that storms may 
  repeatedly move or train over the same areas, especially late 
  this evening. Localized rainfall of one to three inches is 
  likely where this occurs. Combined with the rainfall received 
  this past weekend, this may lead to a few instances of flash 
  flooding. 

* The areas at greatest risk are poor-drainage and urban locals,
  where rapid runoff may cause localized flash flooding. Quickly
  responding creeks and streams may also experience flooding in
  areas that receive the heaviest rainfall. In addition, storms
  are expected to move through the area during and just after the
  evening commute. Motorists should be prepared for torrential 
  downpours and potential flooding as the storms move through. 

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.

&&

$$

DEZ001-002-MDZ008-012-015-NJZ009-010-012>027-PAZ060-061-070-071-
101>106-160330-
/O.CON.KPHI.FF.A.0002.180515T2000Z-180516T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle-Kent-Cecil-Kent MD-Queen Annes-Hunterdon-Somerset-
Middlesex-Western Monmouth-Eastern Monmouth-Mercer-Salem-
Gloucester-Camden-Northwestern Burlington-Ocean-Cumberland-
Atlantic-Cape May-Atlantic Coastal Cape May-Coastal Atlantic-
Coastal Ocean-Southeastern Burlington-Berks-Lehigh-Delaware-
Philadelphia-Western Chester-Eastern Chester-Western Montgomery-
Eastern Montgomery-Upper Bucks-Lower Bucks-
Including the cities of Wilmington, Dover, Elkton, Chestertown, 
Centreville, Flemington, Somerville, New Brunswick, Freehold, 
Sandy Hook, Trenton, Pennsville, Glassboro, Camden, Cherry Hill, 
Moorestown, Mount Holly, Jackson, Millville, Hammonton, 
Cape May Court House, Ocean City, Atlantic City, 
Long Beach Island, Wharton State Forest, Reading, Allentown, 
Media, Philadelphia, Honey Brook, Oxford, West Chester, 
Kennett Square, Collegeville, Pottstown, Norristown, Lansdale, 
Chalfont, Perkasie, Morrisville, and Doylestown
320 PM EDT Tue May 15 2018

...FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL 2 AM EDT WEDNESDAY...

The Flash Flood Watch continues for

* Portions of Delaware, northeast Maryland, New Jersey, and 
  Pennsylvania, including the following areas, in Delaware, Kent 
  and New Castle. In northeast Maryland, Cecil, Kent MD, and 
  Queen Annes. In New Jersey, Atlantic, Atlantic Coastal Cape 
  May, Camden, Cape May, Coastal Atlantic, Coastal Ocean, 
  Cumberland, Eastern Monmouth, Gloucester, Hunterdon, Mercer, 
  Middlesex, Northwestern Burlington, Ocean, Salem, Somerset, 
  Southeastern Burlington, and Western Monmouth. In 
  Pennsylvania, Berks, Delaware, Eastern Chester, Eastern 
  Montgomery, Lehigh, Lower Bucks, Philadelphia, Upper Bucks, 
  Western Chester, and Western Montgomery. 

* Until 2 AM EDT Wednesday

* A line of intense thunderstorms is on track to move into the
  region from the northwest between 4 PM and 8 PM, continuing into
  this evening. There are indications that storms may repeatedly
  move or train over the same areas, especially this evening. 
  Localized rainfall of one to three inches is likely where this 
  occurs. Combined with the rainfall received this past weekend, 
  this may lead to a few instances of flash flooding. 

* The areas at greatest risk are poor-drainage and urban locals,
  where rapid runoff may cause localized flash flooding. Quickly
  responding creeks and streams may also experience flooding in
  areas that receive the heaviest rainfall. In addition, storms
  are expected to move through the area during and just after the
  evening commute. Motorists should be prepared for torrential 
  downpours and potential flooding as the storms move through. 

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.

&&

$$
096 
WGUS61 KPHI 152351
FFAPHI

Flood Watch
National Weather Service Mount Holly NJ
751 PM EDT Tue May 15 2018

PAZ060-061-160100-
/O.CAN.KPHI.FF.A.0002.000000T0000Z-180516T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Berks-Lehigh-
Including the cities of Reading and Allentown
751 PM EDT Tue May 15 2018

...FLASH FLOOD WATCH IS CANCELLED...

The Flash Flood Watch for a portion of east central Pennsylvania
has been cancelled. 

The heavy rain has ended across the area and is no longer 
expected for the rest of tonight. However additional showers are 
expected late tonight into Wednesday which may cause some ponding
on roadways and poor drainage areas.

$$

DEZ001>004-MDZ008-012-015-019-020-NJZ009-010-012>027-PAZ070-071-
101>106-160600-
/O.CON.KPHI.FF.A.0002.000000T0000Z-180516T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle-Kent-Inland Sussex-Delaware Beaches-Cecil-Kent MD-
Queen Annes-Talbot-Caroline-Hunterdon-Somerset-Middlesex-
Western Monmouth-Eastern Monmouth-Mercer-Salem-Gloucester-Camden-
Northwestern Burlington-Ocean-Cumberland-Atlantic-Cape May-
Atlantic Coastal Cape May-Coastal Atlantic-Coastal Ocean-
Southeastern Burlington-Delaware-Philadelphia-Western Chester-
Eastern Chester-Western Montgomery-Eastern Montgomery-Upper Bucks-
Lower Bucks-
Including the cities of Wilmington, Dover, Georgetown, 
Rehoboth Beach, Elkton, Chestertown, Centreville, Easton, Denton,
Flemington, Somerville, New Brunswick, Freehold, Sandy Hook, 
Trenton, Pennsville, Glassboro, Camden, Cherry Hill, Moorestown, 
Mount Holly, Jackson, Millville, Hammonton, Cape May Court House,
Ocean City, Atlantic City, Long Beach Island, 
Wharton State Forest, Media, Philadelphia, Honey Brook, Oxford, 
West Chester, Kennett Square, Collegeville, Pottstown, 
Norristown, Lansdale, Chalfont, Perkasie, Morrisville, 
and Doylestown
751 PM EDT Tue May 15 2018

...FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL 2 AM EDT WEDNESDAY...

The Flash Flood Watch continues for

* Portions of Delaware, northeast Maryland, New Jersey, and 
  southeast Pennsylvania, including the following areas, in 
  Delaware, Delaware Beaches, Inland Sussex, Kent, and New 
  Castle. In northeast Maryland, Caroline, Cecil, Kent MD, Queen 
  Annes, and Talbot. In New Jersey, Atlantic, Atlantic Coastal 
  Cape May, Camden, Cape May, Coastal Atlantic, Coastal Ocean, 
  Cumberland, Eastern Monmouth, Gloucester, Hunterdon, Mercer, 
  Middlesex, Northwestern Burlington, Ocean, Salem, Somerset, 
  Southeastern Burlington, and Western Monmouth. In southeast 
  Pennsylvania, Delaware, Eastern Chester, Eastern Montgomery, 
  Lower Bucks, Philadelphia, Upper Bucks, Western Chester, and 
  Western Montgomery. 

* Until 2 AM EDT Wednesday

* A line of moderate to heavy showers and thunderstorms continues
  to move across the area this evening. There are indications that
  storms may repeatedly move or train over the same areas,
  especially this evening portions of southern New Jersey,
  Delaware and eastern shore of Maryland. Localized rainfall of 
  one to three inches is likely where this occurs. Combined with 
  the rainfall received this past weekend, this may lead to a few 
  instances of flash flooding. 

* The areas at greatest risk are poor-drainage and urban locals, 
  where rapid runoff may cause localized flash flooding. Quickly 
  responding creeks and streams may also experience flooding in 
  areas that receive the heaviest rainfall. In addition, storms 
  are expected to move through the area during and just after 
  the evening commute. Motorists should be prepared for 
  torrential downpours and potential flooding as the storms move 
  through. 

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.

&&

$$
016 
WGUS61 KPHI 160128
FFAPHI

Flood Watch
National Weather Service Mount Holly NJ
928 PM EDT Tue May 15 2018

NJZ009-010-012>015-PAZ070-071-101>106-160230-
/O.CAN.KPHI.FF.A.0002.000000T0000Z-180516T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hunterdon-Somerset-Middlesex-Western Monmouth-Eastern Monmouth-
Mercer-Delaware-Philadelphia-Western Chester-Eastern Chester-
Western Montgomery-Eastern Montgomery-Upper Bucks-Lower Bucks-
Including the cities of Flemington, Somerville, New Brunswick, 
Freehold, Sandy Hook, Trenton, Media, Philadelphia, Honey Brook, 
Oxford, West Chester, Kennett Square, Collegeville, Pottstown, 
Norristown, Lansdale, Chalfont, Perkasie, Morrisville, 
and Doylestown
928 PM EDT Tue May 15 2018

...FLASH FLOOD WATCH IS CANCELLED...

The Flash Flood Watch for portions of New Jersey and southeast
Pennsylvania has been cancelled. 

The heavy rain has ended across the area and is no longer 
expected for the rest of tonight. However additional showers are 
expected late tonight into Wednesday which may cause some ponding 
on roadways and poor drainage areas.

$$

DEZ001>004-MDZ008-012-015-019-020-NJZ016>027-160600-
/O.CON.KPHI.FF.A.0002.000000T0000Z-180516T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle-Kent-Inland Sussex-Delaware Beaches-Cecil-Kent MD-
Queen Annes-Talbot-Caroline-Salem-Gloucester-Camden-
Northwestern Burlington-Ocean-Cumberland-Atlantic-Cape May-
Atlantic Coastal Cape May-Coastal Atlantic-Coastal Ocean-
Southeastern Burlington-
Including the cities of Wilmington, Dover, Georgetown, 
Rehoboth Beach, Elkton, Chestertown, Centreville, Easton, Denton,
Pennsville, Glassboro, Camden, Cherry Hill, Moorestown, 
Mount Holly, Jackson, Millville, Hammonton, Cape May Court House,
Ocean City, Atlantic City, Long Beach Island, 
and Wharton State Forest
928 PM EDT Tue May 15 2018

...FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL 2 AM EDT WEDNESDAY...

The Flash Flood Watch continues for

* Portions of Delaware, northeast Maryland, and southern New 
  Jersey, including the following areas, in Delaware, Delaware 
  Beaches, Inland Sussex, Kent, and New Castle. In northeast 
  Maryland, Caroline, Cecil, Kent MD, Queen Annes, and Talbot. 
  In southern New Jersey, Atlantic, Atlantic Coastal Cape May, 
  Camden, Cape May, Coastal Atlantic, Coastal Ocean, Cumberland, 
  Gloucester, Northwestern Burlington, Ocean, Salem, and 
  Southeastern Burlington. 

* Until 2 AM EDT Wednesday

* A line of moderate to heavy showers and thunderstorms continues
  to move across the area this evening. There are indications that
  storms may repeatedly move or train over the same areas across  
  portions of southern New Jersey, Delaware and eastern shore of 
  Maryland. Localized rainfall of one to three inches is likely 
  where this occurs. Combined with the rainfall received this past
  weekend, this may lead to a few instances of flash flooding. 

* The areas at greatest risk are poor-drainage and urban locals, 
  where rapid runoff may cause localized flash flooding. Quickly 
  responding creeks and streams may also experience flooding in 
  areas that receive the heaviest rainfall. In addition, storms 
  are expected to move through the area during and just after 
  the evening commute. Motorists should be prepared for 
  torrential downpours and potential flooding as the storms move 
  through. 

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.

&&

$$
975 
WGUS61 KPHI 160420
FFAPHI

Flood Watch
National Weather Service Mount Holly NJ
1220 AM EDT Wed May 16 2018

DEZ001>004-MDZ008-012-015-019-020-NJZ016>027-160530-
/O.CAN.KPHI.FF.A.0002.000000T0000Z-180516T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle-Kent-Inland Sussex-Delaware Beaches-Cecil-Kent MD-
Queen Annes-Talbot-Caroline-Salem-Gloucester-Camden-
Northwestern Burlington-Ocean-Cumberland-Atlantic-Cape May-
Atlantic Coastal Cape May-Coastal Atlantic-Coastal Ocean-
Southeastern Burlington-
Including the cities of Wilmington, Dover, Georgetown, 
Rehoboth Beach, Elkton, Chestertown, Centreville, Easton, Denton,
Pennsville, Glassboro, Camden, Cherry Hill, Moorestown, 
Mount Holly, Jackson, Millville, Hammonton, Cape May Court House,
Ocean City, Atlantic City, Long Beach Island, 
and Wharton State Forest
1220 AM EDT Wed May 16 2018

...FLASH FLOOD WATCH IS CANCELLED...

The Flash Flood Watch for portions of Delaware, northeast
Maryland, and southern New Jersey has been cancelled. 

The heavy rain has ended across the area and is no longer 
expected for the rest of the overnight. However, additional 
showers will continue through daybreak which may cause some 
ponding on roadways and poor drainage areas.

$$

MPS

The office that day

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

IssuedProductOfficeCountiesLasted
May 14, 8:45 PM EDTSpecial Weather StatementPHISussex30 min
May 15, 5:35 PM EDTAreal Flood AdvisoryPHINew Castle4 hr
May 15, 5:38 PM EDTSevere Thunderstorm WarningPHINew Castle67 min
May 15, 6:10 PM EDTAreal Flood AdvisoryPHINew Castle4 hr
May 15, 6:35 PM EDTSevere Thunderstorm WarningPHIKent, New Castle40 min
May 15, 6:58 PM EDTAreal Flood AdvisoryPHINew Castle4 hr
May 15, 7:18 PM EDTSevere Thunderstorm WarningPHINew Castle57 min
May 15, 2:49 PM EDTSpecial Weather StatementPHIBerks, Carbon, Lehigh, Monroe, Northampton56 min
May 15, 3:20 PM EDTSevere Thunderstorm WarningPHICarbon, Monroe55 min
May 15, 3:46 PM EDTSevere Thunderstorm WarningPHIBerks, Lehigh, Northampton74 min
May 15, 4:12 PM EDTSevere Thunderstorm WarningPHICarbon, Monroe33 min
May 15, 4:24 PM EDTSpecial Weather StatementPHIBerks51 min
May 15, 4:26 PM EDTTornado WarningPHIBerks, Bucks, Lehigh, Montgomery, Northampton19 min
May 15, 4:41 PM EDTSevere Thunderstorm WarningPHIBerks, Bucks, Chester, Lehigh, Montgomery, Northampton64 min
May 15, 5:12 PM EDTSevere Thunderstorm WarningPHIChester63 min
May 15, 5:14 PM EDTAreal Flood AdvisoryPHIBerks, Chester, Montgomery2 hr
May 15, 5:22 PM EDTSevere Thunderstorm WarningPHIBucks, Chester, Delaware, Montgomery, Philadelphia38 min
May 15, 5:31 PM EDTAreal Flood AdvisoryPHIBucks, Lehigh, Montgomery3 hr
May 15, 5:53 PM EDTSevere Thunderstorm WarningPHIBucks, Chester, Delaware, Montgomery, Philadelphia52 min
May 15, 6:15 PM EDTSevere Thunderstorm WarningPHIChester60 min
May 15, 4:49 PM EDTSpecial Marine WarningPHI86 min
May 15, 6:02 PM EDTSpecial Marine WarningPHI88 min
May 15, 6:12 PM EDTSpecial Marine WarningPHI63 min
May 15, 6:17 PM EDTSpecial Weather StatementPHIBurlington, Camden, Cumberland, Gloucester, Ocean43 min
May 15, 6:46 PM EDTSpecial Weather StatementPHIAtlantic, Cumberland, Ocean, Salem74 min
May 15, 7:14 PM EDTSpecial Marine WarningPHI91 min
May 15, 7:30 PM EDTSpecial Marine WarningPHI90 min

Nearby

Flash Flood Watches in New Jersey, 2018Flash Flood Watches in Pennsylvania, 2018Flash Flood Watches in Maryland, 2018Every flash flood watch in 2018

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.