Coastal Flood Warnings/Watches/Statements
Issued by NWS Boston, MA
Issued by NWS Boston, MA
328
WHUS41 KBOX 211703
CFWBOX
Coastal Hazard Message
National Weather Service Boston/Norton MA
103 PM EDT Thu Aug 21 2025
MAZ020-RIZ006-007-221000-
/O.NEW.KBOX.CF.Y.0006.250822T1000Z-250822T1400Z/
/O.EXB.KBOX.CF.Y.0004.250822T2200Z-250823T0200Z/
/O.CON.KBOX.SU.Y.0001.000000T0000Z-250824T0000Z/
Southern Bristol MA-Washington RI-Newport RI-
103 PM EDT Thu Aug 21 2025
...HIGH SURF ADVISORY REMAINS IN EFFECT UNTIL 8 PM EDT SATURDAY...
...COASTAL FLOOD ADVISORY IN EFFECT FROM 6 AM TO 10 AM EDT
FRIDAY...
...COASTAL FLOOD ADVISORY IN EFFECT FROM 6 PM TO 10 PM EDT
FRIDAY...
* WHAT...Large breaking waves of 10 to 15 feet. Flooding of up to
one foot deep on vulnerable coastal roads and some debris on
roadways around high tide Friday morning and Friday evening.
* WHERE...Massachusetts and Rhode Island South Coast.
* WHEN...For the High Surf Advisory, until 8 PM EDT Saturday. For
the Coastal Flood Advisory, for high tides Friday morning and
Friday evening.
* IMPACTS...Flooding up to one foot deep occurs along the most
vulnerable shoreline locales in Newport, Portsmouth and
Middletown. This includes flooding at parking lots near beaches
in Newport, and a portion of Hazard Road. Shallow flooding also
occurs on several streets in the Common Fence Point area.
Dangerous swimming and surfing conditions and significant beach
erosion.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Do not drive around barricades or through water of unknown depth
during high tide. Take the necessary actions to protect flood-
prone property.
Many ocean beaches are closed. Stay out out of the water due to
dangerous surf conditions. Only view surf at a safe distance, not
from jetties or piers.
&&
&&
Time of high total tides are approximate to the nearest hour.
Westerly RI at Watch Hill
MLLW Categories - Minor 5.0 ft, Moderate 8.0 ft, Major 9.5 ft
MHHW Categories - Minor 2.0 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
-------- --------- --------- --------- ------- --------
21/08 AM 3.4/ 3.9 0.4/ 0.9 0.8/ 1.3 5-6 None
21/09 PM 4.4/ 4.9 1.4/ 1.9 1.3/ 1.8 7 None
22/09 AM 4.2/ 4.7 1.3/ 1.8 1.6/ 2.0 7-8 None
22/09 PM 4.5/ 5.0 1.5/ 2.0 1.4/ 1.9 5 None
23/09 AM 3.5/ 4.0 0.5/ 1.0 0.8/ 1.3 3-4 None
23/10 PM 3.5/ 4.0 0.5/ 1.0 0.5/ 1.0 3 None
Newport Harbor
MLLW Categories - Minor 6.0 ft, Moderate 7.5 ft, Major 9.0 ft
MHHW Categories - Minor 2.1 ft, Moderate 3.6 ft, Major 5.1 ft
Total Total Departure
Day/Time Tide Tide from Norm Waves Flood
ft MLLW ft MHHW ft ft Impact
-------- --------- --------- --------- ------- --------
21/07 AM 4.6/ 5.1 0.7/ 1.1 0.8/ 1.3 3 None
21/07 PM 5.2/ 5.7 1.4/ 1.9 1.1/ 1.6 3 None
22/08 AM 5.5/ 6.0 1.6/ 2.0 1.5/ 2.0 3 None
22/08 PM 5.7/ 6.2 1.9/ 2.3 1.5/ 2.0 3-4 Minor
23/08 AM 4.9/ 5.4 1.0/ 1.5 0.9/ 1.4 2 None
23/09 PM 4.7/ 5.2 0.9/ 1.4 0.6/ 1.1 2 None
Newport South Coast Beaches
MLLW Categories - Minor 6.0 ft, Moderate 7.5 ft, Major 9.0 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
-------- --------- --------- --------- ------- --------
21/07 AM 4.2/ 4.7 0.7/ 1.1 0.7/ 1.1 5-6 None
21/07 PM 5.0/ 5.5 1.5/ 2.0 1.1/ 1.6 7-8 None
22/08 AM 5.2/ 5.7 1.7/ 2.2 1.5/ 2.0 8-10 None
22/08 PM 5.2/ 5.7 1.8/ 2.2 1.4/ 1.9 4-5 None
23/08 AM 4.6/ 5.1 1.1/ 1.6 0.8/ 1.3 3 None
23/09 PM 4.4/ 4.9 0.9/ 1.4 0.5/ 1.0 3 None
Mount Hope Bay near Bristol Point RI
MLLW Categories - Minor 7.0 ft, Moderate 9.5 ft, Major 12.0 ft
MHHW Categories - Minor 2.5 ft, Moderate 5.0 ft, Major 7.5 ft
Total Total Departure
Day/Time Tide Tide from Norm Waves Flood
ft MLLW ft MHHW ft ft Impact
-------- --------- --------- --------- ------- --------
21/07 AM 4.9/ 5.4 0.4/ 0.9 0.8/ 1.3 2 None
21/08 PM 6.0/ 6.5 1.5/ 2.0 1.1/ 1.6 3 None
22/08 AM 5.7/ 6.2 1.2/ 1.7 1.4/ 1.9 3 None
22/08 PM 6.5/ 7.0 2.0/ 2.5 1.5/ 2.0 1-2 None
23/09 AM 5.2/ 5.7 0.7/ 1.1 0.9/ 1.4 1 None
23/09 PM 5.6/ 6.1 1.1/ 1.6 0.7/ 1.1 1-2 None
Mount Hope Bay near Fall River MA
MLLW Categories - Minor 7.0 ft, Moderate 9.5 ft, Major 12.0 ft
MHHW Categories - Minor 2.3 ft, Moderate 4.8 ft, Major 7.3 ft
Total Total Departure
Day/Time Tide Tide from Norm Waves Flood
ft MLLW ft MHHW ft ft Impact
-------- --------- --------- --------- ------- --------
21/07 AM 5.5/ 6.0 0.8/ 1.3 0.8/ 1.3 2 None
21/08 PM 6.2/ 6.8 1.6/ 2.0 1.1/ 1.6 3 None
22/08 AM 6.2/ 6.7 1.5/ 2.0 1.3/ 1.8 3 None
22/08 PM 6.8/ 7.3 2.1/ 2.6 1.6/ 2.0 1-2 Minor
23/09 AM 6.0/ 6.5 1.3/ 1.8 0.9/ 1.4 1 None
23/09 PM 5.9/ 6.4 1.2/ 1.7 0.7/ 1.1 1-2 None
New Bedford Hurricane Barrier
MLLW Categories - Minor 6.0 ft, Moderate 7.5 ft, Major 9.5 ft
MHHW Categories - Minor 2.1 ft, Moderate 3.6 ft, Major 5.6 ft
Total Total Departure
Day/Time Tide Tide from Norm Waves Flood
ft MLLW ft MHHW ft ft Impact
-------- --------- --------- --------- ------- --------
21/07 AM 4.2/ 4.7 0.4/ 0.9 0.6/ 1.1 2-3 None
21/07 PM 5.1/ 5.6 1.2/ 1.7 0.9/ 1.4 4 None
22/08 AM 5.2/ 5.7 1.4/ 1.9 1.3/ 1.8 4 None
22/08 PM 5.7/ 6.2 1.8/ 2.2 1.4/ 1.9 2 None
23/08 AM 4.7/ 5.2 0.9/ 1.4 0.8/ 1.3 1 None
23/09 PM 4.7/ 5.2 0.9/ 1.4 0.6/ 1.1 1-2 None
Westport
MLLW Categories - Minor 6.0 ft, Moderate 8.0 ft, Major 10.0 ft
MHHW Categories - Minor 2.5 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
-------- --------- --------- --------- ------- --------
21/07 AM 4.0/ 4.5 0.5/ 1.0 0.6/ 1.1 4-5 None
21/07 PM 4.7/ 5.2 1.2/ 1.7 1.0/ 1.5 6-7 None
22/08 AM 5.0/ 5.5 1.5/ 2.0 1.4/ 1.9 7-8 None
22/08 PM 5.2/ 5.7 1.7/ 2.2 1.4/ 1.9 3-4 None
23/09 AM 4.5/ 5.0 1.0/ 1.5 0.8/ 1.3 2-3 None
23/09 PM 4.2/ 4.7 0.8/ 1.3 0.5/ 1.0 2 None
&&
$$
RIZ008-221000-
/O.NEW.KBOX.CF.Y.0006.250822T1000Z-250822T1400Z/
/O.EXB.KBOX.CF.Y.0004.250822T2200Z-250823T0200Z/
/O.CON.KBOX.SU.Y.0001.000000T0000Z-250824T0000Z/
Block Island RI-
103 PM EDT Thu Aug 21 2025
...HIGH SURF ADVISORY REMAINS IN EFFECT UNTIL 8 PM EDT SATURDAY...
...COASTAL FLOOD ADVISORY IN EFFECT FROM 6 AM TO 10 AM EDT
FRIDAY...
...COASTAL FLOOD ADVISORY IN EFFECT FROM 6 PM TO 10 PM EDT
FRIDAY...
* WHAT...Large breaking waves of 10 to 15 feet. Flooding of up to
one foot deep on vulnerable coastal roads and some debris on
roadways around high tide Friday morning and Friday evening.
* WHERE...Block Island RI.
* WHEN...For the High Surf Advisory, until 8 PM EDT Saturday. For
the Coastal Flood Advisory, for high tides Friday morning and
Friday evening.
* IMPACTS...Flooding up to one foot deep around high tide on
vulnerable roads, parking lots, and parks. Dangerous swimming
and surfing conditions. Significant beach and dune erosion.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Do not drive around barricades or through water of unknown depth
during high tide. Take the necessary actions to protect flood-
prone property.
Many ocean beaches are closed. Stay out out of the water due to
dangerous surf conditions. Only view surf at a safe distance, not
from jetties or piers.
&&
&&
Time of high total tides are approximate to the nearest hour.
Block Island at Old Harbor
MLLW Categories - Minor 6.0 ft, Moderate 7.5 ft, Major 9.0 ft
MHHW Categories - Minor 2.8 ft, Moderate 4.3 ft, Major 5.8 ft
Total Total Departure
Day/Time Tide Tide from Norm Waves Flood
ft MLLW ft MHHW ft ft Impact
-------- --------- --------- --------- ------- --------
21/07 AM 3.7/ 4.2 0.6/ 1.1 0.7/ 1.1 8-9 None
21/07 PM 4.7/ 5.2 1.5/ 2.0 1.2/ 1.7 11-13 None
22/07 AM 4.7/ 5.2 1.6/ 2.0 1.6/ 2.0 13-15 None
22/08 PM 5.0/ 5.5 1.8/ 2.2 1.4/ 1.9 7-8 Minor
23/08 AM 4.2/ 4.7 1.0/ 1.5 0.8/ 1.3 5-6 None
23/08 PM 3.9/ 4.4 0.7/ 1.1 0.5/ 1.0 5 None
&&
$$
RIZ002-004-005-221000-
/O.NEW.KBOX.CF.Y.0006.250822T1000Z-250822T1400Z/
/O.EXB.KBOX.CF.Y.0004.250822T2200Z-250823T0200Z/
Southeast Providence RI-Eastern Kent RI-Bristol RI-
103 PM EDT Thu Aug 21 2025
...COASTAL FLOOD ADVISORY IN EFFECT FROM 6 AM TO 10 AM EDT
FRIDAY...
...COASTAL FLOOD ADVISORY IN EFFECT FROM 6 PM TO 10 PM EDT
FRIDAY...
* WHAT...Flooding of up to one foot deep on vulnerable coastal
roads around high tide Friday morning and Friday evening.
* WHERE...Locations around Narragansett Bay.
* WHEN...High tides Friday morning and Friday evening.
* IMPACTS...Flooding up to one foot deep on vulnerable roads,
parking lots, and parks.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Do not drive around barricades or through water of unknown depth
during high tide. Take the necessary actions to protect flood-
prone property.
&&
&&
Time of high total tides are approximate to the nearest hour.
Narragansett Bay at Fox Point
MLLW Categories - Minor 7.0 ft, Moderate 9.0 ft, Major 10.5 ft
MHHW Categories - Minor 2.2 ft, Moderate 4.2 ft, Major 5.7 ft
Total Total Departure
Day/Time Tide Tide from Norm Waves Flood
ft MLLW ft MHHW ft ft Impact
-------- --------- --------- --------- ------- --------
21/07 AM 4.7/ 5.2 0.0/ 0.5 0.8/ 1.3 1-2 None
21/08 PM 6.1/ 6.6 1.3/ 1.8 1.1/ 1.6 3 None
22/09 AM 5.5/ 6.0 0.7/ 1.1 1.5/ 2.0 3 None
22/08 PM 6.6/ 7.1 1.8/ 2.2 1.6/ 2.0 1-2 None
23/08 AM 5.0/ 5.5 0.2/ 0.7 1.0/ 1.5 1 None
23/09 PM 5.7/ 6.2 0.9/ 1.4 0.8/ 1.3 1-2 None
Narragansett Bay at Conimicut Point
MLLW Categories - Minor 7.0 ft, Moderate 8.5 ft, Major 10.0 ft
MHHW Categories - Minor 2.4 ft, Moderate 3.9 ft, Major 5.4 ft
Total Total Departure
Day/Time Tide Tide from Norm Waves Flood
ft MLLW ft MHHW ft ft Impact
-------- --------- --------- --------- ------- --------
21/07 AM 5.2/ 5.7 0.7/ 1.1 0.8/ 1.3 2 None
21/08 PM 6.1/ 6.6 1.5/ 2.0 1.1/ 1.6 3 None
22/08 AM 6.2/ 6.7 1.6/ 2.0 1.4/ 1.9 3 None
22/08 PM 6.6/ 7.1 2.0/ 2.5 1.6/ 2.0 1 None
23/09 AM 5.7/ 6.2 1.2/ 1.7 0.9/ 1.4 1 None
23/09 PM 5.5/ 6.0 0.9/ 1.4 0.7/ 1.1 1-2 None
Mount Hope Bay near Bristol Point RI
MLLW Categories - Minor 7.0 ft, Moderate 9.5 ft, Major 12.0 ft
MHHW Categories - Minor 2.5 ft, Moderate 5.0 ft, Major 7.5 ft
Total Total Departure
Day/Time Tide Tide from Norm Waves Flood
ft MLLW ft MHHW ft ft Impact
-------- --------- --------- --------- ------- --------
21/07 AM 4.9/ 5.4 0.4/ 0.9 0.8/ 1.3 2 None
21/08 PM 6.0/ 6.5 1.5/ 2.0 1.1/ 1.6 3 None
22/08 AM 5.7/ 6.2 1.2/ 1.7 1.4/ 1.9 3 None
22/08 PM 6.5/ 7.0 2.0/ 2.5 1.5/ 2.0 1-2 None
23/09 AM 5.2/ 5.7 0.7/ 1.1 0.9/ 1.4 1 None
23/09 PM 5.6/ 6.1 1.1/ 1.6 0.7/ 1.1 1-2 None
Narragansett Bay at Quonset Point
MLLW Categories - Minor 6.0 ft, Moderate 7.5 ft, Major 9.5 ft
MHHW Categories - Minor 1.9 ft, Moderate 3.4 ft, Major 5.4 ft
Total Total Departure
Day/Time Tide Tide from Norm Waves Flood
ft MLLW ft MHHW ft ft Impact
-------- --------- --------- --------- ------- --------
21/07 AM 4.9/ 5.4 0.8/ 1.3 0.8/ 1.3 2 None
21/07 PM 5.6/ 6.1 1.5/ 2.0 1.1/ 1.6 3 None
22/08 AM 5.7/ 6.2 1.7/ 2.2 1.5/ 2.0 3 Minor
22/08 PM 6.0/ 6.5 1.9/ 2.3 1.5/ 2.0 1-2 Minor
23/09 AM 5.2/ 5.7 1.1/ 1.6 0.8/ 1.3 1 None
23/09 PM 5.1/ 5.6 1.0/ 1.5 0.6/ 1.1 1 None
&&
$$
MAZ023-024-221000-
/O.CON.KBOX.SU.Y.0001.000000T0000Z-250824T0000Z/
/O.CON.KBOX.CF.Y.0005.250822T0200Z-250822T0600Z/
/O.CON.KBOX.CF.Y.0004.250823T0200Z-250823T0600Z/
Dukes MA-Nantucket MA-
103 PM EDT Thu Aug 21 2025
...HIGH SURF ADVISORY REMAINS IN EFFECT UNTIL 8 PM EDT SATURDAY...
...COASTAL FLOOD ADVISORY REMAINS IN EFFECT FROM 10 PM THIS
EVENING TO 2 AM EDT FRIDAY...
...COASTAL FLOOD ADVISORY REMAINS IN EFFECT FROM 10 PM FRIDAY TO
2 AM EDT SATURDAY...
* WHAT...Large breaking waves of 15 to 20 feet on south coastal
beaches. Flooding of up to one foot deep on vulnerable coastal
roads around high tide late tonight and late Friday night.
* WHERE...Marthas Vineyard and Nantucket.
* WHEN...For the High Surf Advisory, until 8 PM EDT Saturday. For
the Coastal Flood Advisory, for high tides late tonight and late
Friday night.
* IMPACTS...Roads remain passable. Low lying areas and roads near
Nantucket Harbor, including Easy Street, and Edgartown Harbor
may experience pockets of shallow flooding less than one foot
deep. Dangerous swimming and surfing conditions and significant
beach and dune erosion.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Do not drive around barricades or through water of unknown depth
during high tide. Take the necessary actions to protect flood-
prone property.
Many ocean beaches are closed. Stay out out of the water due to
dangerous surf conditions. Only view surf at a safe distance, not
from near the shore.
&&
&&
Time of high total tides are approximate to the nearest hour.
Edgartown
MLLW Categories - Minor 4.0 ft, Moderate 5.0 ft, Major 7.0 ft
MHHW Categories - Minor 1.3 ft, Moderate 2.3 ft, Major 4.3 ft
Total Total Departure
Day/Time Tide Tide from Norm Waves Flood
ft MLLW ft MHHW ft ft Impact
-------- --------- --------- --------- ------- --------
21/11 AM 2.7/ 3.2 0.0/ 0.5 0.6/ 1.1 5-6 None
21/11 PM 4.2/ 4.7 1.5/ 2.0 1.3/ 1.8 7-8 Minor
22/12 PM 3.6/ 4.1 0.9/ 1.4 1.5/ 2.0 6-7 None
23/12 AM 3.7/ 4.2 1.1/ 1.6 1.1/ 1.6 4 Minor
23/01 PM 2.7/ 3.2 0.0/ 0.5 0.6/ 1.1 3 None
24/01 AM 2.8/ 3.4 0.2/ 0.7 0.2/ 0.8 3 None
Vineyard Haven
MLLW Categories - Minor 4.5 ft, Moderate 6.0 ft, Major 7.0 ft
MHHW Categories - Minor 2.5 ft, Moderate 4.0 ft, Major 5.0 ft
Total Total Departure
Day/Time Tide Tide from Norm Waves Flood
ft MLLW ft MHHW ft ft Impact
-------- --------- --------- --------- ------- --------
21/10 AM 2.2/ 2.7 0.2/ 0.8 0.6/ 1.1 4 None
21/11 PM 3.2/ 3.7 1.3/ 1.8 1.2/ 1.7 5-6 None
22/12 PM 3.2/ 3.7 1.2/ 1.7 1.4/ 1.9 5 None
22/11 PM 3.2/ 3.7 1.2/ 1.7 1.2/ 1.7 3 None
23/12 PM 2.5/ 3.0 0.5/ 1.0 0.7/ 1.1 2-3 None
23/11 PM 2.3/ 2.8 0.4/ 0.9 0.7/ 1.1 2 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
-------- --------- --------- --------- ------- --------
21/11 AM 3.4/ 3.9 -0.2/ 0.2 0.5/ 1.0 6-7 None
22/12 AM 5.2/ 5.7 1.6/ 2.0 1.2/ 1.7 9-10 Minor
22/12 PM 4.5/ 5.0 0.9/ 1.4 1.5/ 2.0 8-9 None
23/12 AM 4.9/ 5.4 1.3/ 1.8 1.1/ 1.6 7 Minor
23/01 PM 3.7/ 4.2 0.1/ 0.6 0.6/ 1.1 5 None
24/02 AM 4.0/ 4.5 0.4/ 0.9 0.2/ 0.8 4 None
&&
$$
MAZ022-221000-
/O.NEW.KBOX.CF.S.0004.250821T2200Z-250823T0600Z/
/O.CON.KBOX.SU.Y.0001.000000T0000Z-250824T0000Z/
Barnstable MA-
103 PM EDT Thu Aug 21 2025
...HIGH SURF ADVISORY REMAINS IN EFFECT UNTIL 8 PM EDT SATURDAY...
...COASTAL FLOOD STATEMENT IN EFFECT FROM 6 PM EDT THIS EVENING
THROUGH LATE FRIDAY NIGHT...
* WHAT...Large breaking waves of 10 to 15 feet on ocean beaches.
Some splashover on vulnerable coastal roads around high tide
tonight through Friday night.
* WHERE...Cape Cod.
* WHEN...For the High Surf Advisory, until 8 PM EDT Saturday.
* IMPACTS...Some water on low lying roads and property around high
tide. Dangerous swimming and surfing conditions and significant
beach erosion.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Many ocean beaches are closed. Stay out out of the water due to
dangerous surf conditions. Only view surf at a safe distance, not
from near the shore, or from jetties or piers.
Avoid any flooded roads during high tide.
&&
&&
Time of high total tides are approximate to the nearest hour.
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
-------- --------- --------- --------- ------- --------
21/07 AM 2.5/ 3.0 0.5/ 1.0 0.6/ 1.1 4 None
21/08 PM 3.5/ 4.0 1.5/ 2.0 1.0/ 1.5 5-6 None
22/08 AM 3.4/ 3.9 1.4/ 1.9 1.4/ 1.9 5-6 None
22/08 PM 3.9/ 4.4 1.9/ 2.3 1.4/ 1.9 3-4 None
23/09 AM 2.7/ 3.2 0.8/ 1.3 0.7/ 1.1 2-3 None
23/09 PM 2.7/ 3.2 0.8/ 1.3 0.4/ 0.9 2 None
Chatham MA - East Coast
MLLW Categories - Minor 9.0 ft, Moderate 11.5 ft, Major 13.0 ft
MHHW Categories - Minor 3.8 ft, Moderate 6.3 ft, Major 7.8 ft
Total Total Departure
Day/Time Tide Tide from Norm Waves Flood
ft MLLW ft MHHW ft ft Impact
-------- --------- --------- --------- ------- --------
21/10 AM 4.5/ 5.0 -0.8/-0.2 0.5/ 1.0 4-5 None
22/12 AM 6.0/ 6.5 0.8/ 1.3 1.0/ 1.5 7-8 None
22/11 AM 5.4/ 5.9 0.2/ 0.7 1.4/ 1.9 9-10 None
22/11 PM 6.1/ 6.6 0.9/ 1.4 1.1/ 1.6 7-8 None
23/01 PM 5.5/ 6.0 0.2/ 0.8 0.5/ 1.0 6 None
24/12 AM 5.4/ 5.9 0.2/ 0.7 0.4/ 0.9 4-5 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
-------- --------- --------- --------- ------- --------
21/12 PM 4.0/ 4.5 -0.5/ 0.0 0.4/ 0.9 4-5 None
22/12 AM 5.7/ 6.2 1.2/ 1.7 0.8/ 1.3 6-7 None
22/01 PM 5.0/ 5.5 0.5/ 1.0 1.2/ 1.7 7-8 None
23/12 AM 5.7/ 6.2 1.2/ 1.7 1.1/ 1.6 6 None
23/01 PM 4.4/ 4.9 -0.2/ 0.3 0.6/ 1.1 5 None
24/01 AM 4.7/ 5.2 0.2/ 0.7 0.2/ 0.7 4 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
-------- --------- --------- --------- ------- --------
21/10 AM 9.3/ 9.8 -0.9/-0.4 0.6/ 1.1 3 None
21/11 PM 11.0/11.5 0.9/ 1.4 0.7/ 1.1 4-5 None
22/11 AM 10.3/10.8 0.2/ 0.7 1.3/ 1.8 7-8 None
23/12 AM 11.5/12.0 1.4/ 1.9 1.1/ 1.6 6-7 None
23/12 PM 10.0/10.5 -0.2/ 0.3 0.6/ 1.1 5 None
24/12 AM 10.8/11.3 0.7/ 1.1 0.5/ 1.0 4 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
-------- --------- --------- --------- ------- --------
21/10 AM 10.1/10.6 -0.5/ 0.0 0.8/ 1.3 3 None
21/11 PM 11.8/12.3 1.3/ 1.8 0.8/ 1.3 3-4 None
22/11 AM 11.3/11.8 0.8/ 1.3 1.6/ 2.0 5 None
23/12 AM 12.0/12.5 1.5/ 2.0 1.1/ 1.6 4 None
23/12 PM 10.6/11.1 0.1/ 0.6 0.7/ 1.1 3 None
24/12 AM 11.3/11.8 0.8/ 1.3 0.6/ 1.1 2-3 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
-------- --------- --------- --------- ------- --------
21/10 AM 8.7/ 9.2 -1.7/-1.2 0.9/ 1.4 3 None
21/11 PM 10.2/10.7 -0.2/ 0.3 0.9/ 1.4 3 None
22/11 AM 9.7/10.2 -0.7/-0.2 1.6/ 2.0 4 None
22/11 PM 10.3/10.8 0.0/ 0.5 1.1/ 1.6 2-3 None
23/12 PM 8.9/ 9.4 -1.5/-1.0 0.6/ 1.1 2 None
24/12 AM 9.6/10.1 -0.8/-0.2 0.5/ 1.0 2 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
-------- --------- --------- --------- ------- --------
21/07 AM 4.2/ 4.7 -0.2/ 0.3 0.6/ 1.1 3 None
21/07 PM 5.2/ 5.7 0.8/ 1.3 0.8/ 1.3 3 None
22/08 AM 5.4/ 5.9 1.0/ 1.5 1.3/ 1.8 3 None
22/08 PM 5.7/ 6.2 1.4/ 1.9 1.4/ 1.9 2-3 None
23/09 AM 5.1/ 5.6 0.7/ 1.1 0.9/ 1.4 1 None
23/09 PM 5.1/ 5.6 0.7/ 1.1 0.7/ 1.1 2 None
&&
$$
MAZ007-019-221000-
/O.NEW.KBOX.CF.S.0004.250821T2200Z-250823T0600Z/
/O.CON.KBOX.SU.Y.0001.250821T1800Z-250824T0000Z/
Eastern Essex MA-Eastern Plymouth MA-
103 PM EDT Thu Aug 21 2025
...HIGH SURF ADVISORY REMAINS IN EFFECT UNTIL 8 PM EDT SATURDAY...
...COASTAL FLOOD STATEMENT IN EFFECT FROM 6 PM EDT THIS EVENING
THROUGH LATE FRIDAY NIGHT...
* WHAT...Large breaking waves of 10 to 15 feet on ocean beaches.
Some splashover on vulnerable coastal roads around high tide
tonight through Friday night.
* WHERE...Eastern Massachusetts coast.
* WHEN...For the High Surf Advisory, until 8 PM EDT Saturday.
* IMPACTS...Some water on low lying roads and property around high
tide. Dangerous swimming and surfing conditions and significant
beach erosion.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Many ocean beaches are closed. Stay out out of the water due to
dangerous surf conditions. Only view surf at a safe distance, not
from near the shore, or from jetties or piers.
Avoid any flooded roads during high tide.
&&
&&
Time of high total tides are approximate to the nearest hour.
Gloucester Harbor
MLLW Categories - Minor 11.5 ft, Moderate 13.0 ft, Major 15.0 ft
MHHW Categories - Minor 1.9 ft, Moderate 3.4 ft, Major 5.4 ft
Total Total Departure
Day/Time Tide Tide from Norm Waves Flood
ft MLLW ft MHHW ft ft Impact
-------- --------- --------- --------- ------- --------
21/11 AM 8.9/ 9.4 -0.8/-0.2 0.4/ 0.9 2-3 None
21/11 PM 10.8/11.3 1.2/ 1.7 0.7/ 1.1 4-5 None
22/11 AM 10.0/10.5 0.4/ 0.9 1.3/ 1.8 7-8 None
23/12 AM 11.2/11.7 1.6/ 2.0 1.1/ 1.6 7 None
23/12 PM 9.6/10.1 0.0/ 0.5 0.6/ 1.1 6 None
24/12 AM 10.2/10.7 0.6/ 1.1 0.2/ 0.8 5-6 None
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
-------- --------- --------- --------- ------- --------
21/11 AM 8.0/ 8.5 -1.6/-1.1 0.4/ 0.9 2-3 None
21/11 PM 9.8/10.3 0.2/ 0.8 0.7/ 1.1 3-4 None
22/11 AM 9.0/ 9.5 -0.6/-0.1 1.3/ 1.8 5 None
23/12 AM 10.1/10.6 0.6/ 1.1 1.1/ 1.6 5-6 None
23/12 PM 8.7/ 9.2 -0.9/-0.4 0.7/ 1.1 4 None
24/12 AM 9.1/ 9.6 -0.5/ 0.0 0.4/ 0.9 4 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
-------- --------- --------- --------- ------- --------
21/10 AM 9.2/ 9.7 -0.6/-0.1 0.7/ 1.1 2-3 None
21/11 PM 11.0/11.5 1.3/ 1.8 0.8/ 1.3 3-4 None
22/11 AM 10.1/10.6 0.4/ 0.9 1.3/ 1.8 6 None
23/12 AM 11.2/11.7 1.5/ 2.0 1.1/ 1.6 5-6 None
23/12 PM 9.7/10.2 0.0/ 0.5 0.6/ 1.1 5 None
24/12 AM 10.4/10.9 0.7/ 1.1 0.5/ 1.0 4-5 None
&&
$$
MAZ021-221000-
/O.CON.KBOX.SU.Y.0001.000000T0000Z-250824T0000Z/
Southern Plymouth MA-
103 PM EDT Thu Aug 21 2025
...HIGH SURF ADVISORY REMAINS IN EFFECT UNTIL 8 PM EDT SATURDAY...
* WHAT...Large breaking waves of up to 4 feet in the surf zone.
* WHERE...Southern Plymouth MA County.
* WHEN...Until 8 PM EDT Saturday.
* IMPACTS...Dangerous swimming and surfing conditions and
localized beach erosion.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Inexperienced swimmers should remain out of the water due to
dangerous surf conditions.
&&
$$
MAZ015-016-221000-
/O.NEW.KBOX.CF.S.0004.250821T2200Z-250823T0600Z/
Suffolk MA-Eastern Norfolk MA-
103 PM EDT Thu Aug 21 2025
...COASTAL FLOOD STATEMENT IN EFFECT FROM 6 PM EDT THIS EVENING
THROUGH LATE FRIDAY NIGHT...
* WHAT...Large breaking waves of 10 to 15 feet on ocean beaches.
Some splashover on vulnerable coastal roads around high tide
tonight through Friday night.
* WHERE...Boston and nearby coastal communities.
* WHEN...High tides late tonight through Friday night.
* IMPACTS...Some water on the lowest lying roads and property.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Do not drive through flooded roadways.
&&
&&
Time of high total tides are approximate to the nearest hour.
Boston Harbor
MLLW Categories - Minor 12.5 ft, Moderate 14.0 ft, Major 15.0 ft
MHHW Categories - Minor 2.2 ft, Moderate 3.7 ft, Major 4.7 ft
Total Total Departure
Day/Time Tide Tide from Norm Waves Flood
ft MLLW ft MHHW ft ft Impact
-------- --------- --------- --------- ------- --------
21/10 AM 9.6/10.1 -0.8/-0.2 0.6/ 1.1 2 None
21/11 PM 11.4/11.9 1.1/ 1.6 0.8/ 1.3 2 None
22/11 AM 10.7/11.2 0.4/ 0.9 1.3/ 1.8 2 None
22/11 PM 11.6/12.1 1.3/ 1.8 1.1/ 1.6 1 None
23/12 PM 10.4/10.9 0.1/ 0.6 0.7/ 1.1 1-2 None
24/12 AM 10.9/11.4 0.6/ 1.1 0.4/ 0.9 2 None
Revere
MLLW Categories - Minor 12.5 ft, Moderate 14.5 ft, Major 16.0 ft
MHHW Categories - Minor 2.6 ft, Moderate 4.6 ft, Major 6.1 ft
Total Total Departure
Day/Time Tide Tide from Norm Waves Flood
ft MLLW ft MHHW ft ft Impact
-------- --------- --------- --------- ------- --------
21/11 AM 9.3/ 9.8 -0.7/-0.2 0.4/ 0.9 1-2 None
21/11 PM 11.2/11.7 1.3/ 1.8 0.8/ 1.3 2 None
22/11 AM 10.4/10.9 0.5/ 1.0 1.3/ 1.8 2 None
22/11 PM 11.3/11.8 1.4/ 1.9 1.1/ 1.6 1 None
23/12 PM 10.1/10.6 0.2/ 0.7 0.6/ 1.1 1 None
24/12 AM 10.5/11.0 0.6/ 1.1 0.2/ 0.8 1-2 None
&&
$$