Coastal flood advisory

A coastal flood advisory is issued by the National Weather Service of the United States when coastal flooding along the coast of the Atlantic Ocean, Pacific Ocean, or the Gulf of Mexico is occurring or imminent, but does not pose a serious threat to lives or property, but rather will simply pose a nuisance to people in the affected area. The flooding must be due to water being forced from the nearby body of water onto land, and not from rainfall. Nor'easters, hurricanes, tropical storms, and thunderstorms can all lead to the issuance of a coastal flood advisory.^[1]

Example

The following is an example of a coastal flood advisory issued by the National Weather Service office in Taunton, Massachusetts.^[2]

062 WHUS41 KBOX 030838 CFWBOX Coastal Hazard Message National Weather Service Boston/Norton MA 338 AM EST Mon Jan 3 2022 MAZ007-015-016-019-022>024-031900- /O.CAN.KBOX.CF.S.0001.220103T1400Z-220103T1900Z/ /O.NEW.KBOX.CF.Y.0001.220103T1400Z-220103T1900Z/ Eastern Essex MA-Suffolk MA-Eastern Norfolk MA- Eastern Plymouth MA-Barnstable MA-Dukes MA-Nantucket MA- 338 AM EST Mon Jan 3 2022 ...COASTAL FLOOD ADVISORY IN EFFECT FROM 9 AM THIS MORNING TO 2 PM EST THIS AFTERNOON... * WHAT...One to two feet of inundation above ground level expected in low-lying areas near shorelines and tidal waterways (3.3 to 13.0 feet Mean Lower Low Water). * WHERE...Eastern Essex MA, Suffolk MA, Eastern Norfolk MA, Eastern Plymouth MA, Barnstable MA, Dukes MA and Nantucket MA Counties. * WHEN...From 9 AM this morning to 2 PM EST this afternoon. * IMPACTS...Coastal flooding is expected along the North Shore from Marblehead northward along the coast to Newburyport. The combination of high tides and a modest storm surge will result in flooding of some immediate coastal roads and some road closures are anticipated. Minor coastal flooding begins on Easy Street in Nantucket. Minor coastal flooding occurs along Morrissey Boulevard in Boston. PRECAUTIONARY/PREPAREDNESS ACTIONS... If travel is required, allow extra time as some roads may be closed. Do not drive around barricades or through water of unknown depth. Take the necessary actions to protect flood-prone property. && && Time of high total tides are approximate to the nearest hour. Merrimack River near Newburyport MA MLLW Categories - Minor 11.0 ft, Moderate 12.0 ft, Major 13.5 ft MHHW Categories - Minor 1.5 ft, Moderate 2.5 ft, Major 4.0 ft Total Total Departure Day/Time Tide Tide from Norm Waves Flood ft MLLW ft MHHW ft ft Impact -------- --------- --------- --------- ------- -------- 03/11 AM 11.0/11.5 1.5/ 2.0 1.0/ 1.5 1 Minor 04/12 AM 9.4/ 9.9 -0.2/ 0.3 1.2/ 1.7 1 None 04/12 PM 10.7/11.2 1.2/ 1.7 0.8/ 1.3 1 Minor 05/01 AM 8.5/ 9.0 -1.1/-0.6 0.2/ 0.7 3 None Gloucester Harbor MLLW Categories - Minor 11.5 ft, Moderate 13.0 ft, Major 15.0 ft MHHW Categories - Minor 2.0 ft, Moderate 3.5 ft, Major 5.5 ft Total Total Departure Day/Time Tide Tide from Norm Waves Flood ft MLLW ft MHHW ft ft Impact -------- --------- --------- --------- ------- -------- 03/11 AM 12.3/12.8 2.7/ 3.2 1.0/ 1.5 3-5 Minor 04/12 AM 10.7/11.2 1.2/ 1.7 1.2/ 1.7 6-7 None 04/12 PM 11.9/12.4 2.3/ 2.8 0.7/ 1.1 4 Minor 05/01 AM 9.8/10.3 0.2/ 0.8 0.2/ 0.7 3-4 None Revere MLLW Categories - Minor 12.5 ft, Moderate 14.5 ft, Major 16.0 ft MHHW Categories - Minor 2.6 ft, Moderate 4.6 ft, Major 6.1 ft Total Total Departure Day/Time Tide Tide from Norm Waves Flood ft MLLW ft MHHW ft ft Impact -------- --------- --------- --------- ------- -------- 03/11 AM 13.0/13.5 3.1/ 3.6 1.2/ 1.7 1 Minor 04/12 AM 11.3/11.8 1.4/ 1.9 1.3/ 1.8 1 None 04/12 PM 12.7/13.2 2.7/ 3.2 0.9/ 1.4 1 Minor 05/01 AM 10.3/10.8 0.4/ 0.9 0.2/ 0.8 2 None Boston Harbor MLLW Categories - Minor 12.5 ft, Moderate 14.5 ft, Major 16.0 ft MHHW Categories - Minor 2.4 ft, Moderate 4.4 ft, Major 5.9 ft Total Total Departure Day/Time Tide Tide from Norm Waves Flood ft MLLW ft MHHW ft ft Impact -------- --------- --------- --------- ------- -------- 03/11 AM 13.0/13.5 2.8/ 3.4 1.2/ 1.7 2-4 Minor 04/12 AM 11.2/11.7 1.1/ 1.6 1.2/ 1.7 4 None 04/12 PM 12.6/13.1 2.5/ 3.0 0.9/ 1.4 3 Minor 05/01 AM 10.4/10.9 0.2/ 0.8 0.4/ 0.9 2 None Scituate MA MLLW Categories - Minor 11.5 ft, Moderate 13.5 ft, Major 15.5 ft MHHW Categories - Minor 1.8 ft, Moderate 3.8 ft, Major 5.8 ft Total Total Departure Day/Time Tide Tide from Norm Waves Flood ft MLLW ft MHHW ft ft Impact -------- --------- --------- --------- ------- -------- 03/11 AM 12.5/13.0 2.7/ 3.2 1.1/ 1.6 3-5 Minor 04/12 AM 10.8/11.3 1.1/ 1.6 1.3/ 1.8 6-7 None 04/12 PM 12.1/12.6 2.3/ 2.8 0.8/ 1.3 4 Minor 05/01 AM 9.9/10.4 0.2/ 0.7 0.2/ 0.8 3 None Chatham - South side MLLW Categories - Minor 9.0 ft, Moderate 10.5 ft, Major 11.5 ft MHHW Categories - Minor 4.5 ft, Moderate 6.0 ft, Major 7.0 ft Total Total Departure Day/Time Tide Tide from Norm Waves Flood ft MLLW ft MHHW ft ft Impact -------- --------- --------- --------- ------- -------- 03/12 PM 6.2/ 6.7 1.7/ 2.2 1.1/ 1.6 4 None 04/01 AM 4.9/ 5.4 0.4/ 0.9 1.2/ 1.7 6-7 None 04/01 PM 5.9/ 6.4 1.4/ 1.9 0.9/ 1.4 3-4 None Wings Neck MLLW Categories - Minor 6.5 ft, Moderate 9.0 ft, Major 11.5 ft MHHW Categories - Minor 2.1 ft, Moderate 4.6 ft, Major 7.1 ft Total Total Departure Day/Time Tide Tide from Norm Waves Flood ft MLLW ft MHHW ft ft Impact -------- --------- --------- --------- ------- -------- 03/08 AM 5.9/ 6.4 1.5/ 2.0 0.8/ 1.3 1-2 None 03/08 PM 4.7/ 5.2 0.4/ 0.9 0.6/ 1.1 4-5 None 04/09 AM 5.7/ 6.2 1.4/ 1.9 0.8/ 1.3 2-3 None 04/09 PM 4.9/ 5.4 0.5/ 1.0 0.6/ 1.1 1 None Provincetown Harbor MLLW Categories - Minor 13.0 ft, Moderate 14.0 ft, Major 15.0 ft MHHW Categories - Minor 2.9 ft, Moderate 3.9 ft, Major 4.9 ft Total Total Departure Day/Time Tide Tide from Norm Waves Flood ft MLLW ft MHHW ft ft Impact -------- --------- --------- --------- ------- -------- 03/11 AM 12.6/13.1 2.5/ 3.0 1.0/ 1.5 4 Minor 04/12 AM 11.0/11.5 0.9/ 1.4 1.2/ 1.7 7 None 04/12 PM 12.1/12.6 2.0/ 2.5 0.6/ 1.1 4-5 None 05/01 AM 10.1/10.6 0.0/ 0.5 0.2/ 0.7 3 None Buzzards Bay at Woods Hole MLLW Categories - Minor 5.5 ft, Moderate 7.0 ft, Major 8.5 ft MHHW Categories - Minor 3.5 ft, Moderate 5.0 ft, Major 6.5 ft Total Total Departure Day/Time Tide Tide from Norm Waves Flood ft MLLW ft MHHW ft ft Impact -------- --------- --------- --------- ------- -------- 03/08 AM 3.9/ 4.4 1.9/ 2.3 0.8/ 1.3 2 None 03/09 PM 3.5/ 4.0 1.5/ 2.0 1.0/ 1.5 5 None 04/09 AM 3.7/ 4.2 1.8/ 2.2 0.8/ 1.3 2-3 None 04/10 PM 3.0/ 3.5 1.0/ 1.5 0.6/ 1.1 1 None Dennis - Sesuit Harbor MLLW Categories - Minor 13.0 ft, Moderate 14.5 ft, Major 16.0 ft MHHW Categories - Minor 2.5 ft, Moderate 4.0 ft, Major 5.5 ft Total Total Departure Day/Time Tide Tide from Norm Waves Flood ft MLLW ft MHHW ft ft Impact -------- --------- --------- --------- ------- -------- 03/11 AM 13.4/13.9 2.8/ 3.4 1.2/ 1.7 3 Minor 04/12 AM 11.9/12.4 1.4/ 1.9 1.5/ 2.0 6 None 04/12 PM 12.8/13.3 2.2/ 2.7 0.7/ 1.1 3-4 Minor 05/01 AM 10.7/11.2 0.2/ 0.7 0.2/ 0.8 1-2 None Chatham MA - East Coast MLLW Categories - Minor 9.0 ft, Moderate 11.5 ft, Major 13.0 ft MHHW Categories - Minor 1.3 ft, Moderate 3.8 ft, Major 5.3 ft Total Total Departure Day/Time Tide Tide from Norm Waves Flood ft MLLW ft MHHW ft ft Impact -------- --------- --------- --------- ------- -------- 03/12 PM 7.1/ 7.6 -0.7/-0.2 1.2/ 1.7 5 None 04/01 AM 6.0/ 6.5 -1.8/-1.3 1.4/ 1.9 7-8 None 04/01 PM 6.7/ 7.2 -1.1/-0.6 0.8/ 1.3 5-6 None Sandwich Harbor MLLW Categories - Minor 12.0 ft, Moderate 14.0 ft, Major 15.0 ft MHHW Categories - Minor 1.7 ft, Moderate 3.7 ft, Major 4.7 ft Total Total Departure Day/Time Tide Tide from Norm Waves Flood ft MLLW ft MHHW ft ft Impact -------- --------- --------- --------- ------- -------- 03/11 AM 11.9/12.4 1.6/ 2.0 1.2/ 1.7 3-4 Minor 04/12 AM 10.4/10.9 0.1/ 0.6 1.4/ 1.9 6-7 None 04/12 PM 11.3/11.8 1.0/ 1.5 0.7/ 1.1 3-4 None 05/01 AM 9.3/ 9.8 -1.1/-0.6 0.2/ 0.8 2 None Vineyard Haven MLLW Categories - Minor 5.0 ft, Moderate 6.5 ft, Major 8.5 ft MHHW Categories - Minor 3.0 ft, Moderate 4.5 ft, Major 6.5 ft Total Total Departure Day/Time Tide Tide from Norm Waves Flood ft MLLW ft MHHW ft ft Impact -------- --------- --------- --------- ------- -------- 03/12 PM 3.1/ 3.6 1.1/ 1.6 1.1/ 1.6 2-3 None 04/12 AM 3.2/ 3.7 1.2/ 1.7 1.5/ 2.0 4-5 None 04/12 PM 2.7/ 3.2 0.8/ 1.3 0.9/ 1.4 2 None 05/01 AM 2.1/ 2.6 0.1/ 0.6 0.4/ 0.9 1 None Nantucket Harbor MLLW Categories - Minor 5.0 ft, Moderate 6.5 ft, Major 8.0 ft MHHW Categories - Minor 1.4 ft, Moderate 2.9 ft, Major 4.4 ft Total Total Departure Day/Time Tide Tide from Norm Waves Flood ft MLLW ft MHHW ft ft Impact -------- --------- --------- --------- ------- -------- 03/12 PM 5.2/ 5.7 1.6/ 2.0 1.2/ 1.7 3-4 Minor 04/01 AM 4.5/ 5.0 0.9/ 1.4 1.6/ 2.0 5-7 None 04/01 PM 4.7/ 5.2 1.2/ 1.7 0.8/ 1.3 3-4 Minor && $$ Nocera

See also

• Severe weather terminology (United States)

References

1. Baltimore/Washington National Weather Service Forecast Office. "Coastal Flood Advisory". erh.noaa.gov. Retrieved 17 May 2011.
2. "IEM::Valid Time Event Code". Iowa State University. Iowa Environmental Mesonet. Retrieved 8 January 2022.

External links

• National Weather Service