Alert archive / New Jersey / Flash Flood Watches in 2017

Flash Flood Watch 1, NWS Philadelphia/Mount Holly

June 18, 20174 states

NWS Philadelphia/Mount Holly issued this flash flood watch at Jun 18, 2017, 3:30 AM EDT for 4 states. It took effect at Jun 19, 2017, 12:00 PM EDT. It was in force for 6 hr.

The area

The counties it named.

The facts

Issued
Jun 18, 2017, 3:30 AM EDT (07:30 UTC)
In effect from
Jun 19, 2017, 12:00 PM EDT
Expired
Jun 19, 2017, 6:22 PM EDT
In force
6 hr
Issued by
NWS Philadelphia/Mount Holly
Flood severity
None
All 22 counties

New Castle County, DE, Cecil County, MD, Burlington County, NJ, Camden County, NJ, Gloucester County, NJ, Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Morris County, NJ, Salem County, NJ, Somerset County, NJ, Sussex 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), 68 km from the middle of the area, began a volume at 07:34 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 00:00Z, 7.5 hours before the alert went out and 202 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 00:00Z on 2017-06-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 40 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 00:00Z on 2017-06-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 99 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
40 J/kg
Mixed-layer CIN
-147 J/kg
Mixed-layer LCL
539 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
99 m²/s²
0-3 km storm-relative helicity
122 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

157 
WGUS61 KPHI 180730
FFAPHI

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Mount Holly NJ
330 AM EDT Sun Jun 18 2017

DEZ001-MDZ008-NJZ008>010-012-013-015>019-PAZ070-071-101>106-
182100-
/O.NEW.KPHI.FF.A.0001.170619T1600Z-170620T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle-Cecil-Morris-Hunterdon-Somerset-Middlesex-
Western Monmouth-Mercer-Salem-Gloucester-Camden-
Northwestern Burlington-Delaware-Philadelphia-Western Chester-
Eastern Chester-Western Montgomery-Eastern Montgomery-Upper Bucks-
Lower Bucks-
Including the cities of Wilmington, Elkton, Morristown, 
Flemington, Somerville, New Brunswick, Freehold, Trenton, 
Pennsville, Glassboro, Camden, Cherry Hill, Moorestown, 
Mount Holly, Media, Philadelphia, Honey Brook, Oxford, 
West Chester, Kennett Square, Collegeville, Pottstown, 
Norristown, Lansdale, Chalfont, Perkasie, Morrisville, 
and Doylestown
330 AM EDT Sun Jun 18 2017

...FLASH FLOOD WATCH IN EFFECT FROM MONDAY AFTERNOON THROUGH 
MONDAY EVENING...

The National Weather Service in Mount Holly has issued a

* Flash Flood Watch for the Pennsylvania counties of Bucks, 
  Montgomery, Chester, Delaware and Philadelphia, for the New 
  Jersey counties of Morris, Hunterdon, Somerset, Mercer, 
  Middlesex, Monmouth, northwestern Burlington, Camden, Gloucester
  and Salem, for New Castle County in Delaware, and for Cecil 
  County in Maryland

* From Monday afternoon through Monday evening.

* Showers and thunderstorms are forecast to affect the region 
  from Monday into Monday night. Rainfall amounts of 1 to 2 inches
  are expected to be common with localized totals of 3 to 4 
  inches possible. The heaviest of the rain is anticipated to fall
  on Monday afternoon and Monday evening.

* The heavy rain will cause roadway flooding and flooding in 
  areas of poor drainage. Small streams and creeks may go out of 
  their banks.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead 
to flash flooding. Flash flooding is a very dangerous situation.

Please monitor the forecast today and Monday for updated 
information. Be prepared to take action should Flash Flood 
Warnings be issued on Monday.

&&

$$

Iovino
4 follow-up statements
701 
WGUS61 KPHI 181935
FFAPHI

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Mount Holly NJ
335 PM EDT Sun Jun 18 2017

...HEAVY RAIN AND FLASH FLOODING POSSIBLE MONDAY AFTERNOON AND
EVENING NIGHT...

NJZ001-007-PAZ060>062-190345-
/O.EXA.KPHI.FF.A.0001.170619T1600Z-170620T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Sussex-Warren-Berks-Lehigh-Northampton-
Including the cities of Newton, Washington, Reading, Allentown, 
Bethlehem, and Easton
335 PM EDT Sun Jun 18 2017

...FLASH FLOOD WATCH IN EFFECT FROM MONDAY AFTERNOON THROUGH
MONDAY EVENING...

The National Weather Service in Mount Holly has expanded the

* Flash Flood Watch to include the Lehigh Valley and Berks County
  in eastern Pennsylvania, and far northwestern New Jersey.

* Monday afternoon and evening

* Showers and thunderstorms on Monday will contain torrential
  downpours. Rainfall amounts of 1 to 2 inches will be common with
  localized totals of 3 to 4 inches possible. The bulk of these
  rainfall amounts could fall in a very short period. The heaviest
  rain will likely fall during the afternoon and early evening. 

* Flash flooding of creeks, streams and roadways will be possible,
  especially in urban and poor drainage areas. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead
to flash flooding. Flash flooding is a very dangerous situation.

Please monitor the forecast today and Monday for updated
information. Be prepared to take action should Flash Flood
Warnings be issued on Monday.

&&

$$

DEZ001-MDZ008-NJZ008>010-012-013-015>019-PAZ070-071-101>106-
190345-
/O.CON.KPHI.FF.A.0001.170619T1600Z-170620T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle-Cecil-Morris-Hunterdon-Somerset-Middlesex-
Western Monmouth-Mercer-Salem-Gloucester-Camden-
Northwestern Burlington-Delaware-Philadelphia-Western Chester-
Eastern Chester-Western Montgomery-Eastern Montgomery-Upper Bucks-
Lower Bucks-
Including the cities of Wilmington, Elkton, Morristown, 
Flemington, Somerville, New Brunswick, Freehold, Trenton, 
Pennsville, Glassboro, Camden, Cherry Hill, Moorestown, 
Mount Holly, Media, Philadelphia, Honey Brook, Oxford, 
West Chester, Kennett Square, Collegeville, Pottstown, 
Norristown, Lansdale, Chalfont, Perkasie, Morrisville, 
and Doylestown
335 PM EDT Sun Jun 18 2017

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM MONDAY AFTERNOON
THROUGH MONDAY EVENING...

The Flash Flood Watch continues for

* Portions of northern Delaware, northeast Maryland, New Jersey, 
  and southeast Pennsylvania, including the following areas, in 
  northern Delaware, New Castle. In northeast Maryland, Cecil. 
  In New Jersey, Camden, Gloucester, Hunterdon, Mercer, 
  Middlesex, Morris, Northwestern Burlington, Salem, Somerset, 
  and Western Monmouth. In southeast Pennsylvania, Delaware, 
  Eastern Chester, Eastern Montgomery, Lower Bucks, 
  Philadelphia, Upper Bucks, Western Chester, and Western 
  Montgomery. 

* Monday afternoon and evening

* Showers and thunderstorms on Monday will contain torrential
  downpours. Rainfall amounts of 1 to 2 inches will be common with
  localized totals of 3 to 5 inches possible. The bulk of these
  rainfall amounts could fall in a very short period. The heaviest
  rain will likely fall during the late afternoon and evening.
 
* Flash flooding of creeks, streams and roadways will be possible,
  especially in urban and poor drainage areas. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead
to flash flooding. Flash flooding is a very dangerous situation.

Please monitor the forecast today and Monday for updated
information. Be prepared to take action should Flash Flood
Warnings be issued on Monday.

&&

$$
Klein
198 
WGUS61 KPHI 190748
FFAPHI

Flood Watch
National Weather Service Mount Holly NJ
348 AM EDT Mon Jun 19 2017

DEZ001-MDZ008-NJZ001-007>010-012-013-015>019-PAZ060>062-070-071-
101>106-192100-
/O.CON.KPHI.FF.A.0001.170619T1600Z-170620T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle-Cecil-Sussex-Warren-Morris-Hunterdon-Somerset-
Middlesex-Western Monmouth-Mercer-Salem-Gloucester-Camden-
Northwestern Burlington-Berks-Lehigh-Northampton-Delaware-
Philadelphia-Western Chester-Eastern Chester-Western Montgomery-
Eastern Montgomery-Upper Bucks-Lower Bucks-
Including the cities of Wilmington, Elkton, Newton, Washington, 
Morristown, Flemington, Somerville, New Brunswick, Freehold, 
Trenton, Pennsville, Glassboro, Camden, Cherry Hill, Moorestown, 
Mount Holly, Reading, Allentown, Bethlehem, Easton, Media, 
Philadelphia, Honey Brook, Oxford, West Chester, Kennett Square, 
Collegeville, Pottstown, Norristown, Lansdale, Chalfont, 
Perkasie, Morrisville, and Doylestown
348 AM EDT Mon Jun 19 2017

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM NOON EDT TODAY
THROUGH THIS EVENING...

The Flash Flood Watch continues for

* southeastern Pennsylvania, northern, central and southwestern 
  New Jersey, northern Delaware and extreme northeastern Maryland.

* From noon EDT today through this evening

* Showers and thunderstorms this afternoon and this evening will 
  contain torrential downpours. Rainfall amounts of 1 to 2 inches 
  will be common with localized totals of 3 to 5 inches possible. 
  The bulk of these rainfall amounts could fall in a very short 
  period. The heaviest rain will likely fall during the late 
  afternoon and evening. 

* Flash flooding of creeks, streams and roadways will be 
  possible, especially in urban and poor drainage areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead 
to flash flooding. Flash flooding is a very dangerous situation.

Please monitor the forecast today for updated information. Be 
prepared to take action should Flash Flood Warnings be issued.

&&

$$

Iovino
562 
WGUS61 KPHI 191921
FFAPHI

Flood Watch
National Weather Service Mount Holly NJ
321 PM EDT Mon Jun 19 2017

DEZ001-MDZ008-NJZ001-007>010-012-013-015>019-PAZ060>062-070-071-
101>106-200400-
/O.CON.KPHI.FF.A.0001.000000T0000Z-170620T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle-Cecil-Sussex-Warren-Morris-Hunterdon-Somerset-
Middlesex-Western Monmouth-Mercer-Salem-Gloucester-Camden-
Northwestern Burlington-Berks-Lehigh-Northampton-Delaware-
Philadelphia-Western Chester-Eastern Chester-Western Montgomery-
Eastern Montgomery-Upper Bucks-Lower Bucks-
Including the cities of Wilmington, Elkton, Newton, Washington, 
Morristown, Flemington, Somerville, New Brunswick, Freehold, 
Trenton, Pennsville, Glassboro, Camden, Cherry Hill, Moorestown, 
Mount Holly, Reading, Allentown, Bethlehem, Easton, Media, 
Philadelphia, Honey Brook, Oxford, West Chester, Kennett Square, 
Collegeville, Pottstown, Norristown, Lansdale, Chalfont, 
Perkasie, Morrisville, and Doylestown
321 PM EDT Mon Jun 19 2017

...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 Pennsylvania, including the following areas, in northern 
  Delaware, New Castle. In northeast Maryland, Cecil. In New 
  Jersey, Camden, Gloucester, Hunterdon, Mercer, Middlesex, 
  Morris, Northwestern Burlington, Salem, Somerset, Sussex, 
  Warren, and Western Monmouth. In Pennsylvania, Berks, 
  Delaware, Eastern Chester, Eastern Montgomery, Lehigh, Lower 
  Bucks, Northampton, Philadelphia, Upper Bucks, Western 
  Chester, and Western Montgomery. 

* Until midnight EDT tonight.

* Showers and thunderstorms this afternoon and this evening will
  contain torrential downpours. Rainfall amounts of 1 to 2 inches
  will be common with localized totals of 3 to 5 inches possible.
  The bulk of these rainfall amounts could fall in a very short
  period of time. The heaviest rain will likely occur through
  early this evening. 

* Flash flooding of creeks, streams and roadways will be 
  possible, especially in urban and poor drainage areas. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead
to flash flooding. Flash flooding is a very dangerous situation.

Please monitor the forecast today for updated information. Be
prepared to take action should Flash Flood Warnings be issued.

&&

$$
034 
WGUS61 KPHI 192222
FFAPHI

Flood Watch
National Weather Service Mount Holly NJ
622 PM EDT Mon Jun 19 2017

DEZ001-MDZ008-NJZ001-007>010-012-013-015>019-PAZ060>062-070-071-
101>106-192330-
/O.CAN.KPHI.FF.A.0001.000000T0000Z-170620T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle-Cecil-Sussex-Warren-Morris-Hunterdon-Somerset-
Middlesex-Western Monmouth-Mercer-Salem-Gloucester-Camden-
Northwestern Burlington-Berks-Lehigh-Northampton-Delaware-
Philadelphia-Western Chester-Eastern Chester-Western Montgomery-
Eastern Montgomery-Upper Bucks-Lower Bucks-
Including the cities of Wilmington, Elkton, Newton, Washington, 
Morristown, Flemington, Somerville, New Brunswick, Freehold, 
Trenton, Pennsville, Glassboro, Camden, Cherry Hill, Moorestown, 
Mount Holly, Reading, Allentown, Bethlehem, Easton, Media, 
Philadelphia, Honey Brook, Oxford, West Chester, Kennett Square, 
Collegeville, Pottstown, Norristown, Lansdale, Chalfont, 
Perkasie, Morrisville, and Doylestown
622 PM EDT Mon Jun 19 2017

...FLASH FLOOD WATCH IS CANCELLED...

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

The drenching line of showers and thunderstorms has moved out of
the area as it nears the coast. The threat of very heavy rain and
flash flooding has ended, and therefore the flash flood watch has
been cancelled.

$$

Gorse

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 17, 8:35 PM EDTMarine Dense Fog AdvisoryPHI13 hr

Nearby

Flash Flood Watches in New Jersey, 2017Flash Flood Watches in Pennsylvania, 2017Flash Flood Watches in Maryland, 2017Every flash flood watch in 2017

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.