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Tidal Observations Coastal Flood Thresholds, Impacts and Analysis Surge Models
Astronomical Tidal Predictions Inundation/Impact Resources Latest Coastal Flood Forecasts

 

LATEST COASTAL FLOOD FORECASTS
 
NYCCFWOKX Coastal Flood WATCH / WARNING / Advisory  
NYCHWOOKX Hazardous Weather OUTLOOK  
 

 Understanding the Minor, Moderate, Major Coastal Flood Thresholds

Understanding Coastal Flood Terminology

 


 

TIDAL OBSERVATIONS


Bridgeport, CT Stamford Hurricane Barrier New Haven, CT Silver Eel Pond, Fishers Island, NY New London, CT Hudson River, Hudson at Piermont Smith Point Bridge, Shirley, NY Great South Bay at Lindenhurst, NY Hudson Bay at Freeport, NY Reynolds Channel at Point Lookout, NY East Rockaway Inlet at Atlantic Beach, NY Jamaica Bay at Inwood, NY Sandy Hook, NJ RockawayInlet near Floyd Bennet Field, NY Bergen Point at West Reach, NY The Battery, NY Kings Point, NY Montauk, NY West Pond at Glen Cove Oreint Harbor at Orient NY Peconic River at Riverhead Old Field Watch Hill East Moriches East Hampton

 


 

COASTAL FLOODING THRESHOLDS, IMPACTS and ANALYSIS
 
Long Island Sound
Station
Coastal Flood Benchmarks
(MLLW / MHHW / NGVD)
Tidal Impacts/Analysis
Connecticut
 

Minor -8.9' / 1.6'
Moderate - 10.4' / 3.1'
Major - 11.4 ' / 4.1'
   MLLW - 3.6' = MSL
   MLLW - 7.3' = MHHW

New Haven
(NOS)

Minor - 8.6' / 1.9'
Moderate - 9.2' / 2.5'
Major - 10.5'
/ 3.8'
   MLLW - 3.3' = MSL
   MLLW - 6.7' = MHHW

Minor -5.0' / 1.9'
Moderate - 6.0' / 2.9'
Major - 7.8'
/ 4.7'
   MLLW - 1.5' = MSL
   MLLW - 3.1' = MHHW

Stamford
(USACE)
Site ID# 01209788

Minor -9.4' / 1.5' / 6.4'
  Close Hurr. Barrier -10.0' / 2.1' / 7.0'
Moderate - 11.0' / 3.1' / 8.0'
Major - 12.4' / 4.5' / 9.4'
  Overtop Hurr. Barrier -20.0' / 12.1 ' / 17.0'

   MLLW - 3.0' = NGVD
   MLLW - 7.9' = MHHW

New York
 
Old Field
(USGS)

Site ID# 01304057

Minor - 9.2' / 1.9' / 6.5'
Moderate -  10.2' / 2.9' / 7.5'
Major -  12.2' / 4.9' / 9.5'
  MLLW - 2.7' = NGVD
  MLLW - 7.3' = MHHW

Minor - 10.0' / 2.2'
  NYC Minor - 10.5' / 2.7'
Moderate - 10.5' / 2.7'
  NYC Moderate - 11.0' / 3.2'
Major - 13.0' / 5.2'

  MLLW - 3.9' = MSL
   MLLW - 7.8' = MHHW
   MLLW - 4.0' = NAVD
   MHHW + 3.9' = NAVD

West Pond (Glen Cove)
(USGS)

Site ID# 01302600

Minor - 10.1' / 2.2' / 7.0'
Moderate - 11.1' / 3.2' / 8.0'
Major - 13.1' / 5.2' / 10.0'
  MLLW - 3.1' = NGVD
  MLLW - 7.9' = MHHW

 

 

Hudson River
Station
Coastal Flood Benchmarks
(MLLW / MHHW / NGVD)
Tidal Impacts/Analysis
Piermont
(USGS)
Site ID# 01376269

Minor -  6.9' / 2.9' / 6.0'
Moderate -  8.4' / 4.4' / 7.5'
Major -  

   MLLW - 0.9' = NGVD
   MLLW - 4.0' = MHHW

 

 

New York Harbor
Station
Coastal Flood Benchmarks
(MLLW / MHHW / NGVD / NAVD)
Tidal Impacts/Analysis
New York
 
Battery
(NOS)

Minor - 7.2' / 2.1'
Moderate - 8.5' / 3.4'
  Start to overtop seawall - 9.0' / 3.9'
Major - 9.6' / 4.6'

   MLLW - 2.6' = MSL
   MLLW - 5.0' = MHHW
   MLLW - 2.8' = NAVD
   MHHW + 2.2' = NAVD

Minor - 7.2' / 1.7'
Moderate - 8.5' / 3.0'
Major - 9.6' / 4.1'

   MLLW - 2.8' = MSL
   MLLW - 5.5' = MHHW

Great Kills Harbor
(USGS)
Site ID# 01376562

Minor - 7.2' / 1.9' / 5.5'
Moderate - 8.2' / 2.9' / 6.5'
Major - 9.2' / 3.9' / 7.5'

   MLLW - 1.7' = NGVD
   MLLW - 5.3' = MHHW

New Jersey
 

Minor - 7.0' / 1.8'
Moderate - 7.7' / 2.5'
Major - 8.7' / 3.5'
   MLLW - 2.6' = MSL
   MLLW - 5.2' = MHHW

 

 

South Shore of NYC/LI and Eastern LI
Station
Coastal Flood Benchmarks
(MLLW / MHHW / NGVD / NAVD)
Tidal Impacts/Analysis
South Shore Bays
 
Rockaway Inlet
(USGS)
Site ID# 01311875

Minor - 7.3' / 1.8' / 5.5' / 4.4'
Moderate - 8.3' / 2.8' / 6.5' / 5.4'
Major - 9.3' / 3.8' / 7.5' / 6.4'
   MLLW - 1.8' = NGVD
   MLLW - 5.6' = MHHW
   MLLW - 2.9' = NAVD
   MHHW + 2.6' = NAVD

Jamaica Bay
(USGS)
Site ID# 01311850

Minor - 7.5' / 1.6' / 5.5'/ 4.4'
Moderate - 8.2' / 2.3' / 6.2' / 5.1'
Major - 9.0' / 3.1' / 7.0' / 5.9'
   MLLW - 2.0' = NGVD
   MLLW - 5.9' = MHHW
   MLLW - 3.1' = NAVD
   MHHW + 2.8' = NAVD

East Rockaway Inlet
(USGS)
Site ID# 01311145

Minor - 6.0' / 1.0' / 4.5'
Moderate - 7.0' / 2.0' / 5.5'
Major - 8.0' / 3.0' / 6.5'
  MLLW - 1.5' = NGVD
  MLLW - 5.0' = MHHW

Freeport
(USGS)
Site ID# 01310521

Minor - 5.7' / 1.2' / 4.5'
Moderate - 6.2' / 1.7' / 5.0'
Major - 6.9' / 2.4' / 5.7'
   MLLW - 1.2' = NGVD
   MLLW - 4.5' = MHHW

Hog Island
(USGS)
Site ID# 01311143

Minor - 6.0' / 1.0' / 4.5'
Moderate - 7.0' / 2.0' / 5.5'
Major - 8.0' / 3.0' / 6.5'
   MLLW - 1.5' = NGVD
   MLLW - 5.0' = MHHW

Reynolds Channel
(USGS)
Site ID# 01310740

Minor - 5.8' / 1.1' / 4.5'
Moderate - 6.8' / 2.1' / 5.5'
Major - 7.8' / 3.1' / 6.5'
  MLLW - 1.3' = NGVD
  MLLW - 4.7' = MHHW

Lindenhurst
(USGS)
Site ID# 01309225

Minor - 3.1' / 1.6' / 3.5'
Moderate - 3.6' / 2.1' / 4.0'
Major - 4.1' / 2.6' / 4.5'
  MLLW + 0.4' = NGVD
  MLLW - 1.5' = MHHW

West Sayville
(USGS)
Site ID# 01306402

Minor - 3.0' / 1.7' / 3.5'
Moderate - 3.5' / 2.2' / 4.0'
Major - 4.0' / 2.7' / 4.5'
  MLLW + 0.5' = NGVD
  MLLW - 1.3' = MHHW

Watch Hill, Fire I.
(USGS)
Site ID# 01305575

Minor - 3.1' / 1.7' / 3.5'
Moderate - 3.6' / 2.2' / 4.0'
Major - 4.1' / 2.7' / 4.5'
   MLLW + 0.4' = NGVD
   MLLW - 1.4' = MHHW

 

 

 
Moriches Bay
(USGS)
Site ID# 01304920

Minor - 4.4' / 1.8' / 4.0'
Moderate - 5.4' / 2.8' / 5.0'
Major - 6.4' / 3.8' / 6.0'
   MLLW - 0.4' = NGVD
   MLLW - 2.6' = MHHW

 

Shinnecock Bay at Ponquogue NY
(USGS)
Site ID# 01304746

Minor - 4.9' / 1.7' / 4.0'
Moderate - 5.9' / 2.7' / 5.0'
Major - 6.9' / 3.7' / 6.0'
   MLLW - 0.9' = NGVD
   MLLW - 3.2' = MHHW

 

East Hampton
(SUNYSB)

 

 
Eastern LI
 

Minor - 4.5' / 2.0'
Moderate - 5.3' / 2.8'
Major - 7.0' / 4.5'

   MLLW - 1.2' = MSL
   MLLW - 2.5' = MHHW

Orient Harbor
(USGS
)
Site ID# 01304200

Minor - 4.7' / 1.9' / 4'
Moderate - 5.7' / 2.9' / 5'
Major - 6.7' / 3.9' / 6'
   MLLW - .7' = NGVD
   MLLW - 2.8' = MHHW

Riverhead
(USGS
)
Site ID# 01304562

Minor - 5.6' / 2.3' / 4.5'
Moderate - 6.3' / 3.0' / 5.2'
Major - 7.1' / 3.8' / 6'
  MLLW - 1.1' = NGVD
  MLLW - 3.3' = MHHW

 

 


 

STORM SURGE GUIDANCE

 

Extratropical
Extratropical and Tropical
Tropical

 


 

TIDAL PREDICTIONS

 


 

INUNDATION AND IMPACT RESOURCES
 
OCM Coastal Flood Viewer OCM's Coastal Flood Exposure Mapper Climate Central - Surging Seas - Coastal Flood Viewer and Risk Finder USGS Coastal Change Hazard Portal

OCM Sea Level Rise Viewer

OCM Coastal Flood Exposure Mapper

Climate Central - Surging Seas Coastal Mapping Tools

USGS Coastal Change Hazards