Alert archive / New Jersey / Coastal Flood Advisories in 2021

Coastal Flood Advisory 21, NWS Philadelphia/Mount Holly

November 6, 2021Sussex County, Delaware; Atlantic County, Cape May County, New Jersey

NWS Philadelphia/Mount Holly issued this coastal flood advisory at Nov 6, 2021, 3:59 PM EDT for Sussex County, Delaware; Atlantic County, Cape May County, New Jersey. It took effect at Nov 7, 2021, 7:00 AM EST. It was in force for 7 hr.

The area

The counties it named.

The facts

Issued
Nov 6, 2021, 3:59 PM EDT (19:59 UTC)
In effect from
Nov 7, 2021, 7:00 AM EST
Expired
Nov 7, 2021, 2:00 PM EST
In force
7 hr
Issued by
NWS Philadelphia/Mount Holly

Counties Sussex County, DE, Atlantic County, NJ, Cape May County, NJ

The radar

The Dover AFB radar (KDOX), 52 km from the middle of the area, began a volume at 20:01 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.

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 12:00Z, 8.0 hours before the alert went out and 134 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 12:00Z on 2021-11-06Temperature 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 12:00Z on 2021-11-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 23 square meters per square second.1939587897117Sfc1 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
1194 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
23 m²/s²
0-3 km storm-relative helicity
238 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

488 
WHUS41 KPHI 061959
CFWPHI

Coastal Hazard Message
National Weather Service Mount Holly NJ
359 PM EDT Sat Nov 6 2021

DEZ003-004-NJZ022>025-070900-
/O.NEW.KPHI.CF.Y.0021.211107T1200Z-211107T1900Z/
Inland Sussex-Delaware Beaches-Atlantic-Cape May-
Atlantic Coastal Cape May-Coastal Atlantic-
359 PM EDT Sat Nov 6 2021

...COASTAL FLOOD ADVISORY IN EFFECT FROM 7 AM TO 2 PM EST
SUNDAY...

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

* WHERE...Tidal areas of Atlantic and Cape May Counties in New
  Jersey and Sussex County in Delaware.

* WHEN...From 7 AM to 2 PM EST Sunday.

* IMPACTS...At this level, flooding begins on the most 
  vulnerable roads in coastal and bayside communities, and along 
  inland 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 Bay at Lewes
MLLW Categories - Minor 6.0 ft, Moderate 7.0 ft, Major 8.0 ft
MHHW Categories - Minor 1.3 ft, Moderate 2.3 ft, Major 3.3 ft

             Total      Total    Departure          
 Day/Time    Tide       Tide     from Norm   Flood  
            ft MLLW    ft MHHW       ft      Impact 
 --------  ---------  ---------  ---------  --------
 06/11 PM     5.0        0.3       0.7       None    
 07/10 AM     6.4        1.8       0.7      Minor    
 07/11 PM     4.8        0.2       0.7       None    
 08/11 AM     6.3        1.7       0.8      Minor    
 09/12 AM     4.4       -0.2       0.5       None    
 09/12 PM     5.6        1.0       0.4       None

Atlantic Ocean at Atlantic City
MLLW Categories - Minor 6.0 ft, Moderate 7.0 ft, Major 8.0 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 
 --------  ---------  ---------  ---------  --------
 06/09 PM     4.9        0.3       0.7       None    
 07/09 AM     6.3        1.7       0.7      Minor    
 07/09 PM     4.7        0.1       0.7       None    
 08/10 AM     6.2        1.6       0.8      Minor    
 08/10 PM     4.3       -0.3       0.6       None    
 09/11 AM     5.5        0.9       0.4       None

Great Egg Harbor Bay at Ocean City
MLLW Categories - Minor 5.3 ft, Moderate 6.3 ft, Major 7.3 ft
MHHW Categories - Minor 1.3 ft, Moderate 2.3 ft, Major 3.3 ft

             Total      Total    Departure          
 Day/Time    Tide       Tide     from Norm   Flood  
            ft MLLW    ft MHHW       ft      Impact 
 --------  ---------  ---------  ---------  --------
 06/10 PM     4.4        0.4       0.4       None    
 07/09 AM     5.5        1.5       0.3      Minor    
 07/09 PM     3.9       -0.1       0.3       None    
 08/10 AM     5.6        1.6       0.5      Minor    
 08/11 PM     3.8       -0.2       0.2       None    
 09/11 AM     4.9        0.9       0.1       None

Cape May Harbor at Cape May
MLLW Categories - Minor 6.2 ft, Moderate 7.2 ft, Major 8.2 ft
MHHW Categories - Minor 1.1 ft, Moderate 2.1 ft, Major 3.1 ft

             Total      Total    Departure          
 Day/Time    Tide       Tide     from Norm   Flood  
            ft MLLW    ft MHHW       ft      Impact 
 --------  ---------  ---------  ---------  --------
 06/10 PM     5.3        0.2       0.5       None    
 07/09 AM     6.7        1.6       0.5      Minor    
 07/09 PM     4.8       -0.3       0.5       None    
 08/10 AM     6.6        1.5       0.6      Minor    
 08/10 PM     4.5       -0.6       0.4       None    
 09/11 AM     5.9        0.8       0.3       None

&&

$$

CMS
3 follow-up statements
064 
WHUS41 KPHI 070858
CFWPHI

Coastal Hazard Message
National Weather Service Mount Holly NJ
358 AM EST Sun Nov 7 2021

DEZ003-004-NJZ022>025-071900-
/O.CON.KPHI.CF.Y.0021.211107T1200Z-211107T1900Z/
Inland Sussex-Delaware Beaches-Atlantic-Cape May-
Atlantic Coastal Cape May-Coastal Atlantic-
358 AM EST Sun Nov 7 2021

...COASTAL FLOOD ADVISORY REMAINS IN EFFECT FROM 7 AM THIS
MORNING TO 2 PM EST THIS AFTERNOON...

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

* WHERE...Tidal areas of Atlantic and Cape May Counties in New
  Jersey and Sussex County in Delaware.

* WHEN...From 7 AM this morning to 2 PM EST this afternoon.

* IMPACTS...At this level, flooding begins on the most 
  vulnerable roads in coastal and bayside communities, and along 
  inland 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 Bay at Lewes
MLLW Categories - Minor 6.0 ft, Moderate 7.0 ft, Major 8.0 ft
MHHW Categories - Minor 1.3 ft, Moderate 2.3 ft, Major 3.3 ft

             Total      Total    Departure          
 Day/Time    Tide       Tide     from Norm   Flood  
            ft MLLW    ft MHHW       ft      Impact 
 --------  ---------  ---------  ---------  --------
 06/11 PM     5.0        0.3       0.7       None    
 07/10 AM     6.4        1.8       0.7      Minor    
 07/11 PM     4.8        0.2       0.7       None    
 08/11 AM     6.3        1.7       0.8      Minor    
 09/12 AM     4.4       -0.2       0.5       None    
 09/12 PM     5.6        1.0       0.4       None

Atlantic Ocean at Atlantic City
MLLW Categories - Minor 6.0 ft, Moderate 7.0 ft, Major 8.0 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 
 --------  ---------  ---------  ---------  --------
 06/09 PM     4.9        0.3       0.7       None    
 07/09 AM     6.3        1.7       0.7      Minor    
 07/09 PM     4.7        0.1       0.7       None    
 08/10 AM     6.2        1.6       0.8      Minor    
 08/10 PM     4.3       -0.3       0.6       None    
 09/11 AM     5.5        0.9       0.4       None

Great Egg Harbor Bay at Ocean City
MLLW Categories - Minor 5.3 ft, Moderate 6.3 ft, Major 7.3 ft
MHHW Categories - Minor 1.3 ft, Moderate 2.3 ft, Major 3.3 ft

             Total      Total    Departure          
 Day/Time    Tide       Tide     from Norm   Flood  
            ft MLLW    ft MHHW       ft      Impact 
 --------  ---------  ---------  ---------  --------
 06/10 PM     4.4        0.4       0.4       None    
 07/09 AM     5.5        1.5       0.3      Minor    
 07/09 PM     3.9       -0.1       0.3       None    
 08/10 AM     5.6        1.6       0.5      Minor    
 08/11 PM     3.8       -0.2       0.2       None    
 09/11 AM     4.9        0.9       0.1       None

Cape May Harbor at Cape May
MLLW Categories - Minor 6.2 ft, Moderate 7.2 ft, Major 8.2 ft
MHHW Categories - Minor 1.1 ft, Moderate 2.1 ft, Major 3.1 ft

             Total      Total    Departure          
 Day/Time    Tide       Tide     from Norm   Flood  
            ft MLLW    ft MHHW       ft      Impact 
 --------  ---------  ---------  ---------  --------
 06/10 PM     5.3        0.2       0.5       None    
 07/09 AM     6.7        1.6       0.5      Minor    
 07/09 PM     4.8       -0.3       0.5       None    
 08/10 AM     6.6        1.5       0.6      Minor    
 08/10 PM     4.5       -0.6       0.4       None    
 09/11 AM     5.9        0.8       0.3       None

&&

$$

Meola
460 
WHUS41 KPHI 071258
CFWPHI

Coastal Hazard Message
National Weather Service Mount Holly NJ
758 AM EST Sun Nov 7 2021

DEZ003-004-NJZ022>025-071900-
/O.CON.KPHI.CF.Y.0021.000000T0000Z-211107T1900Z/
Inland Sussex-Delaware Beaches-Atlantic-Cape May-
Atlantic Coastal Cape May-Coastal Atlantic-
758 AM EST Sun Nov 7 2021

...COASTAL FLOOD ADVISORY REMAINS IN EFFECT UNTIL 2 PM EST THIS
AFTERNOON...

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

* WHERE...Tidal areas of Atlantic and Cape May Counties in New 
  Jersey and Sussex County in Delaware.

* WHEN...From 7 AM this morning to 2 PM EST this afternoon.

* IMPACTS...At this level, flooding begins on the most 
  vulnerable roads in coastal and bayside communities, and along 
  inland 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 Bay at Lewes
MLLW Categories - Minor 6.0 ft, Moderate 7.0 ft, Major 8.0 ft
MHHW Categories - Minor 1.3 ft, Moderate 2.3 ft, Major 3.3 ft

             Total      Total    Departure          
 Day/Time    Tide       Tide     from Norm   Flood  
            ft MLLW    ft MHHW       ft      Impact 
 --------  ---------  ---------  ---------  --------
 07/10 AM     6.5        1.8       0.8      Minor    
 07/11 PM     4.9        0.2       0.8       None    
 08/11 AM     6.5        1.8       1.0      Minor    
 08/11 PM     4.6       -0.0       0.8       None    
 09/12 PM     5.7        1.0       0.5       None    
 10/01 AM     4.1       -0.5       0.4       None

Atlantic Ocean at Atlantic City
MLLW Categories - Minor 6.0 ft, Moderate 7.0 ft, Major 8.0 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 
 --------  ---------  ---------  ---------  --------
 07/09 AM     6.5        1.9       0.9      Minor    
 07/09 PM     4.8        0.2       0.8       None    
 08/10 AM     6.4        1.8       1.0      Minor    
 08/10 PM     4.5       -0.1       0.8       None    
 09/11 AM     5.7        1.1       0.6       None    
 09/11 PM     4.0       -0.6       0.5       None

Great Egg Harbor Bay at Ocean City
MLLW Categories - Minor 5.3 ft, Moderate 6.3 ft, Major 7.3 ft
MHHW Categories - Minor 1.3 ft, Moderate 2.3 ft, Major 3.3 ft

             Total      Total    Departure          
 Day/Time    Tide       Tide     from Norm   Flood  
            ft MLLW    ft MHHW       ft      Impact 
 --------  ---------  ---------  ---------  --------
 07/09 AM     5.6        1.6       0.4      Minor    
 07/09 PM     4.0        0.0       0.4       None    
 08/10 AM     5.7        1.7       0.6      Minor    
 08/11 PM     4.0        0.0       0.4       None    
 09/11 AM     5.0        1.0       0.2       None    
 10/12 AM     3.5       -0.5       0.1       None

Cape May Harbor at Cape May
MLLW Categories - Minor 6.2 ft, Moderate 7.2 ft, Major 8.2 ft
MHHW Categories - Minor 1.1 ft, Moderate 2.1 ft, Major 3.1 ft

             Total      Total    Departure          
 Day/Time    Tide       Tide     from Norm   Flood  
            ft MLLW    ft MHHW       ft      Impact 
 --------  ---------  ---------  ---------  --------
 07/09 AM     6.4        1.3       0.2      Minor    
 07/09 PM     4.7       -0.4       0.4       None    
 08/10 AM     6.7        1.6       0.7      Minor    
 08/10 PM     4.8       -0.3       0.7       None    
 09/11 AM     6.0        0.9       0.4       None    
 10/12 AM     4.3       -0.8       0.3       None

&&

$$
568 
WHUS41 KPHI 071848
CFWPHI

Coastal Hazard Message
National Weather Service Mount Holly NJ
148 PM EST Sun Nov 7 2021

DEZ003-004-NJZ022>025-072000-
/O.EXP.KPHI.CF.Y.0021.000000T0000Z-211107T1900Z/
Inland Sussex-Delaware Beaches-Atlantic-Cape May-
Atlantic Coastal Cape May-Coastal Atlantic-
148 PM EST Sun Nov 7 2021

...COASTAL FLOOD ADVISORY WILL EXPIRE AT 2 PM EST THIS
AFTERNOON...

Tidal flooding from today's high tide is ending. Therefore, the
coastal flood advisory will be allowed to expire. Another round of
minor tidal flooding is expected on Monday, with additional
advisories likely. Stay tuned to the latest forecasts.

$$

CMS

The office that day

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

IssuedProductOfficeCountiesLasted
Nov 6, 4:14 AM EDTCoastal Flood AdvisoryPHIKent, Sussex10 hr
Nov 5, 9:50 PM EDTSmall Craft AdvisoryPHI4 days
Nov 6, 3:27 AM EDTGale WatchPHI11 hr
Nov 6, 3:27 AM EDTSmall Craft AdvisoryPHI4 days

Nearby

Coastal Flood Advisories in New Jersey, 2021Coastal Flood Advisories in Delaware, 2021Every coastal flood advisory in 2021

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.