Alert archive / Delaware / Coastal Flood Statements in 2020

Coastal Flood Statement 15, NWS Philadelphia/Mount Holly

August 16, 2020Sussex County, Delaware; Ocean County, New Jersey

NWS Philadelphia/Mount Holly issued this coastal flood statement at Aug 16, 2020, 10:52 PM EDT for Sussex County, Delaware; Ocean County, New Jersey. It took effect at Aug 16, 2020, 11:00 PM EDT. It was in force for 4 hr.

The area

The counties it named.

The facts

Issued
Aug 16, 2020, 10:52 PM EDT (02:52 UTC)
In effect from
Aug 16, 2020, 11:00 PM EDT
Expired
Aug 17, 2020, 3:00 AM EDT
In force
4 hr
Issued by
NWS Philadelphia/Mount Holly

Counties Sussex County, DE, Ocean County, NJ

The radar

The Dover AFB radar (KDOX), 75 km from the middle of the area, began a volume at 02:59 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, 2.9 hours before the alert went out and 158 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 2020-08-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2020-08-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -56 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
592 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
-56 m²/s²
0-3 km storm-relative helicity
23 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

649 
WHUS41 KPHI 170252
CFWPHI

Coastal Hazard Message
National Weather Service Mount Holly NJ
1052 PM EDT Sun Aug 16 2020

NJZ020-026-170700-
/O.EXP.KPHI.CF.Y.0020.000000T0000Z-200817T0300Z/
/O.NEW.KPHI.CF.S.0015.200817T0300Z-200817T0700Z/
Ocean-Coastal Ocean-
1052 PM EDT Sun Aug 16 2020

...COASTAL FLOOD ADVISORY WILL EXPIRE AT 11 PM EDT THIS EVENING...
...LINGERING MINOR FLOODING ALONG BARNEGAT BAY OVERNIGHT...

* WHAT...Up to a half foot of inundation above ground level is
  expected in low-lying areas near shorelines and tidal waterways.

* WHERE...Barnegat Bay and the tidal waterways that flow into it.

* WHEN...Until 3:00 AM Monday.

* IMPACTS...Minor roadway flooding is possible.

$$

DEZ003-004-170700-
/O.EXP.KPHI.CF.Y.0020.000000T0000Z-200817T0300Z/
/O.NEW.KPHI.CF.S.0015.200817T0300Z-200817T0700Z/
Inland Sussex-Delaware Beaches-
1052 PM EDT Sun Aug 16 2020

...COASTAL FLOOD ADVISORY WILL EXPIRE AT 11 PM EDT THIS EVENING...
...LINGERING MINOR FLOODING ALONG LITTLE ASSAWOMAN BAY 
OVERNIGHT...

* WHAT...Up to a half foot of inundation above ground level is 
  expected in low-lying areas near shorelines and tidal waterways.

* WHERE...Little Assawoman Bay and the tidal waterways that flow 
  into it.

* WHEN...Until 3:00 AM Monday.

* IMPACTS...Minor roadway flooding is possible.

&&

$$

NJZ014-027-170400-
/O.EXP.KPHI.CF.Y.0020.000000T0000Z-200817T0300Z/
Eastern Monmouth-Southeastern Burlington-
1052 PM EDT Sun Aug 16 2020

...COASTAL FLOOD ADVISORY WILL EXPIRE AT 11 PM EDT THIS EVENING...

Water levels will continue to decrease overnight. The Coastal
Flood Advisory will expire at 11:00 PM.

$$

NJZ021>025-170400-
/O.EXP.KPHI.CF.Y.0020.000000T0000Z-200817T0300Z/
Cumberland-Atlantic-Cape May-Atlantic Coastal Cape May-
Coastal Atlantic-
1052 PM EDT Sun Aug 16 2020

...COASTAL FLOOD ADVISORY WILL EXPIRE AT 11 PM EDT THIS EVENING...

Water levels will continue to decrease overnight. The Coastal
Flood Advisory will expire at 11:00 PM.

$$

DEZ002-170400-
/O.EXP.KPHI.CF.Y.0020.000000T0000Z-200817T0300Z/
Kent-
1052 PM EDT Sun Aug 16 2020

...COASTAL FLOOD ADVISORY WILL EXPIRE AT 11 PM EDT THIS EVENING...

Water levels will continue to decrease overnight. The Coastal
Flood Advisory will expire at 11:00 PM.

$$

DEZ001-NJZ016-170400-
/O.CON.KPHI.CF.Y.0020.000000T0000Z-200817T0400Z/
New Castle-Salem-
1052 PM EDT Sun Aug 16 2020

...COASTAL FLOOD ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT EDT
TONIGHT...

* WHAT...Up to one foot of inundation above ground level is is
  expected in low-lying areas near shorelines and tidal waterways.

* WHERE...Tidal areas in New Castle County, Delaware and Salem 
  County, New Jersey.

* WHEN...Until midnight.

* IMPACTS...At this level, flooding begins on the most vulnerable
  roads along tidal waterways. Some partial or full road closures
  are possible.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Coastal Flood Advisory means that minor tidal flooding is 
expected. Minor tidal flooding often results in some road 
closures. Usually, the most vulnerable roadways will flood.

Do not leave your vehicle at a location that is prone to tidal 
flooding. Do not drive your vehicle through flood waters. The 
water may be deeper than you think it is. You will be putting 
yourself in danger and your vehicle may be damaged, leading to 
costly repairs.

Visit the Advanced Hydrologic Prediction Service at 
water.weather.gov/ahps for additional water level and flood impact
information for your local tide gauge.

&&

Time of high total tides are approximate to the nearest hour.

Delaware River at Reedy Point
MLLW Categories - Minor 7.2 ft, Moderate 8.2 ft, Major 9.2 ft
MHHW Categories - Minor 1.4 ft, Moderate 2.4 ft, Major 3.4 ft

             Total      Total    Departure          
 Day/Time    Tide       Tide     from Norm   Flood  
            ft MLLW    ft MHHW       ft      Impact 
 --------  ---------  ---------  ---------  --------
 17/11 AM     6.9        1.1       1.5       None    
 17/11 PM     7.6        1.8       1.0      Minor    
 18/11 AM     6.1        0.3       0.5       None    
 19/12 AM     7.1        1.3       0.4       None    
 19/12 PM     6.0        0.2       0.2       None

&&

$$

NJZ017>019-PAZ070-071-106-170700-
/O.CON.KPHI.CF.Y.0020.000000T0000Z-200817T0700Z/
Gloucester-Camden-Northwestern Burlington-Delaware-Philadelphia-
Lower Bucks-
1052 PM EDT Sun Aug 16 2020

...COASTAL FLOOD ADVISORY REMAINS IN EFFECT UNTIL 3 AM EDT
MONDAY...

* WHAT...Up to one foot of inundation above ground level is 
  expected in low-lying areas near shorelines and tidal waterways.

* WHERE...The tidal Delaware River and its tidal tributaries.

* WHEN...Until 3:00 AM Monday.

* IMPACTS...At this level, flooding begins on the most vulnerable
  roads along tidal waterways. Some partial or full road closures
  are possible.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Coastal Flood Advisory means that minor tidal flooding is 
expected. Minor tidal flooding often results in some road 
closures. Usually, the most vulnerable roadways will flood.

Do not leave your vehicle at a location that is prone to tidal 
flooding. Do not drive your vehicle through flood waters. The 
water may be deeper than you think it is. You will be putting 
yourself in danger and your vehicle may be damaged, leading to 
costly repairs.

Visit the Advanced Hydrologic Prediction Service at 
water.weather.gov/ahps for additional water level and flood impact
information for your local tide gauge.

&&

Time of high total tides are approximate to the nearest hour.

Delaware River at Philadelphia
MLLW Categories - Minor 8.2 ft, Moderate 9.2 ft, Major 10.2 ft
MHHW Categories - Minor 1.5 ft, Moderate 2.5 ft, Major 3.5 ft

             Total      Total    Departure          
 Day/Time    Tide       Tide     from Norm   Flood  
            ft MLLW    ft MHHW       ft      Impact 
 --------  ---------  ---------  ---------  --------
 17/01 AM     8.4        1.7       1.3      Minor    
 17/01 PM     7.3        0.6       1.3       None    
 18/01 AM     8.4        1.7       1.1      Minor    
 18/02 PM     7.1        0.4       0.9       None    
 19/02 AM     8.3        1.6       0.9      Minor    
 19/03 PM     7.1        0.4       0.7       None

Delaware River at Burlington
MLLW Categories - Minor 9.3 ft, Moderate 10.3 ft, Major 11.3 ft
MHHW Categories - Minor 1.6 ft, Moderate 2.6 ft, Major 3.6 ft

             Total      Total    Departure          
 Day/Time    Tide       Tide     from Norm   Flood  
            ft MLLW    ft MHHW       ft      Impact 
 --------  ---------  ---------  ---------  --------
 17/01 AM     9.5        1.8       1.5      Minor    
 17/02 PM     8.4        0.7       1.5       None    
 18/02 AM     9.4        1.7       1.2      Minor    
 18/03 PM     8.4        0.7       1.2       None    
 19/03 AM     9.5        1.8       1.1      Minor    
 19/04 PM     8.5        0.8       1.0       None

&&

$$

Iovino
2 follow-up statements
538 
WHUS41 KPHI 170356
CFWPHI

Coastal Hazard Message
National Weather Service Mount Holly NJ
1156 PM EDT Sun Aug 16 2020

DEZ001-NJZ016-170500-
/O.EXP.KPHI.CF.Y.0020.000000T0000Z-200817T0400Z/
New Castle-Salem-
1156 PM EDT Sun Aug 16 2020

...COASTAL FLOOD ADVISORY WILL EXPIRE AT MIDNIGHT EDT TONIGHT...

Water levels will continue to decrease overnight. The Coastal 
Flood Advisory will expire at midnight.

$$

NJZ017>019-PAZ070-071-106-170700-
/O.CON.KPHI.CF.Y.0020.000000T0000Z-200817T0700Z/
Gloucester-Camden-Northwestern Burlington-Delaware-Philadelphia-
Lower Bucks-
1156 PM EDT Sun Aug 16 2020

...COASTAL FLOOD ADVISORY REMAINS IN EFFECT UNTIL 3 AM EDT
MONDAY...

* WHAT...Up to one foot of inundation above ground level is 
  expected in low-lying areas near shorelines and tidal waterways.

* WHERE...The tidal Delaware River and its tidal tributaries.

* WHEN...Until 3:00 AM Monday.

* IMPACTS...At this level, flooding begins on the most vulnerable
  roads along tidal waterways. Some partial or full road closures
  are possible.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Coastal Flood Advisory means that minor tidal flooding is 
expected. Minor tidal flooding often results in some road 
closures. Usually, the most vulnerable roadways will flood.

Do not leave your vehicle at a location that is prone to tidal 
flooding. Do not drive your vehicle through flood waters. The 
water may be deeper than you think it is. You will be putting 
yourself in danger and your vehicle may be damaged, leading to 
costly repairs.

Visit the Advanced Hydrologic Prediction Service at 
water.weather.gov/ahps for additional water level and flood impact
information for your local tide gauge.

&&

Time of high total tides are approximate to the nearest hour.

Delaware River at Philadelphia
MLLW Categories - Minor 8.2 ft, Moderate 9.2 ft, Major 10.2 ft
MHHW Categories - Minor 1.5 ft, Moderate 2.5 ft, Major 3.5 ft

             Total      Total    Departure          
 Day/Time    Tide       Tide     from Norm   Flood  
            ft MLLW    ft MHHW       ft      Impact 
 --------  ---------  ---------  ---------  --------
 17/01 AM     8.4        1.7       1.3      Minor    
 17/01 PM     7.3        0.6       1.3       None    
 18/01 AM     8.4        1.7       1.1      Minor    
 18/02 PM     7.1        0.4       0.9       None    
 19/02 AM     8.3        1.6       0.9      Minor    
 19/03 PM     7.1        0.4       0.7       None

Delaware River at Burlington
MLLW Categories - Minor 9.3 ft, Moderate 10.3 ft, Major 11.3 ft
MHHW Categories - Minor 1.6 ft, Moderate 2.6 ft, Major 3.6 ft

             Total      Total    Departure          
 Day/Time    Tide       Tide     from Norm   Flood  
            ft MLLW    ft MHHW       ft      Impact 
 --------  ---------  ---------  ---------  --------
 17/01 AM     9.5        1.8       1.5      Minor    
 17/02 PM     8.4        0.7       1.5       None    
 18/02 AM     9.4        1.7       1.2      Minor    
 18/03 PM     8.4        0.7       1.2       None    
 19/03 AM     9.5        1.8       1.1      Minor    
 19/04 PM     8.5        0.8       1.0       None

&&

$$

NJZ020-026-170700-
/O.CON.KPHI.CF.S.0015.000000T0000Z-200817T0700Z/
Ocean-Coastal Ocean-
1156 PM EDT Sun Aug 16 2020

...LINGERING MINOR FLOODING ALONG BARNEGAT BAY OVERNIGHT...

* WHAT...Up to a half foot of inundation above ground level is 
  expected in low-lying areas near shorelines and tidal waterways.

* WHERE...Barnegat Bay and the tidal waterways that flow into it.

* WHEN...Until 3:00 AM Monday.

* IMPACTS...Minor roadway flooding is possible.

$$

DEZ003-004-170700-
/O.CON.KPHI.CF.S.0015.000000T0000Z-200817T0700Z/
Inland Sussex-Delaware Beaches-
1156 PM EDT Sun Aug 16 2020

...LINGERING MINOR FLOODING ALONG LITTLE ASSAWOMAN BAY 
OVERNIGHT...

* WHAT...Up to a half foot of inundation above ground level is 
  expected in low-lying areas near shorelines and tidal waterways.

* WHERE...Little Assawoman Bay and the tidal waterways that flow 
  into it.

* WHEN...Until 3:00 AM Monday.

* IMPACTS...Minor roadway flooding is possible.

$$

Iovino
657 
WHUS41 KPHI 170654
CFWPHI

Coastal Hazard Message
National Weather Service Mount Holly NJ
254 AM EDT Mon Aug 17 2020

NJZ017>019-PAZ070-071-106-170800-
/O.EXP.KPHI.CF.Y.0020.000000T0000Z-200817T0700Z/
Gloucester-Camden-Northwestern Burlington-Delaware-Philadelphia-
Lower Bucks-
254 AM EDT Mon Aug 17 2020

...COASTAL FLOOD ADVISORY WILL EXPIRE AT 3 AM EDT EARLY THIS
MORNING...

Water levels will continue to decrease early this morning. The 
Coastal Flood Advisory will expire at 3:00 AM.

$$

NJZ020-026-170800-
/O.EXP.KPHI.CF.S.0015.000000T0000Z-200817T0700Z/
Ocean-Coastal Ocean-
254 AM EDT Mon Aug 17 2020

...LINGERING MINOR FLOODING ALONG BARNEGAT BAY HAS ENDED...

Water levels will continue to decrease early this morning. The 
lingering minor flooding along Barnegat Bay and the tidal 
waterways that flow into it has ended.

$$

DEZ003-004-170800-
/O.EXP.KPHI.CF.S.0015.000000T0000Z-200817T0700Z/
Inland Sussex-Delaware Beaches-
254 AM EDT Mon Aug 17 2020

...LINGERING MINOR FLOODING ALONG LITTLE ASSAWOMAN BAY HAS 
ENDED...

Water levels will continue to decrease early this morning. The 
lingering minor flooding along Little Assawoman Bay and the tidal 
waterways that flow into it has ended.

$$

Iovino

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 17, 5:08 AM EDTCoastal Flood AdvisoryPHIKent, New Castle, Sussex23 hr
Aug 17, 10:44 AM EDTRip Current StatementPHISussex11 hr
Aug 17, 5:38 PM EDTSevere Thunderstorm WarningPHINew Castle37 min
Aug 17, 6:16 PM EDTSevere Thunderstorm WarningPHINew Castle16 min
Aug 17, 6:06 PM EDTSpecial Weather StatementPHIHunterdon39 min

Nearby

Coastal Flood Statements in Delaware, 2020Coastal Flood Statements in New Jersey, 2020Every coastal flood statement 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.