Alert archive / Massachusetts / Coastal Flood Statements in 2021
Coastal Flood Statement 5, NWS Boston/Norton, MA
NWS Boston/Norton, MA issued this coastal flood statement at Apr 29, 2021, 3:29 PM EDT for 5 counties in Massachusetts. It took effect at Apr 29, 2021, 11:00 PM EDT. It was in force for 5 hr.
The area
The counties it named.
The facts
- Issued
- Apr 29, 2021, 3:29 PM EDT (19:29 UTC)
- In effect from
- Apr 29, 2021, 11:00 PM EDT
- Expired
- Apr 30, 2021, 4:00 AM EDT
- In force
- 5 hr
- Issued by
- NWS Boston/Norton, MA
Counties Barnstable County, MA, Essex County, MA, Norfolk County, MA, Plymouth County, MA, Suffolk County, MA
The radar
The Boston radar (KBOX), 35 km from the middle of the area, began a volume at 19:33 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
Gray, ME (KGYX), launched 12:00Z, 7.5 hours before the alert went out and 197 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.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 482 m above ground
- 0-6 km bulk shear
- 68 kt
- 0-1 km storm-relative helicity
- -4 m²/s²
- 0-3 km storm-relative helicity
- 91 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
342
WHUS41 KBOX 291929
CFWBOX
Coastal Hazard Message
National Weather Service Boston/Norton MA
329 PM EDT Thu Apr 29 2021
MAZ007-015-016-019-022-300800-
/O.NEW.KBOX.CF.S.0005.210430T0300Z-210430T0800Z/
Eastern Essex MA-Suffolk MA-Eastern Norfolk MA-
Eastern Plymouth MA-Barnstable MA-
329 PM EDT Thu Apr 29 2021
* WHAT...Up to one foot of inundation above ground level
expected in low-lying areas near shorelines and tidal
waterways (3.9 to 13.2 feet Mean Lower Low Water).
* WHERE...Eastern Massachusetts coast including Cape Cod.
* WHEN...Within a few hours of the approximate 1 to 3 am Friday
morning high tide.
* IMPACTS...Very Minor coastal flooding occurs along Morrissey Boulevard
in Boston. Other vulnerable shore roads may also experience
minor nuisance flooding.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Do not drive through flooded roadways.
&&
&&
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
-------- --------- --------- --------- ------- --------
29/02 PM 8.7/ 9.2 -0.9/-0.4 -0.2/ 0.2 2 None
30/02 AM 10.9/11.4 1.4/ 1.9 0.7/ 1.1 3 Minor
30/03 PM 9.1/ 9.6 -0.5/ 0.0 0.5/ 1.0 3 None
01/03 AM 10.2/10.7 0.7/ 1.1 0.2/ 0.8 3 None
01/04 PM 8.4/ 8.9 -1.1/-0.7 0.1/ 0.6 2 None
02/04 AM 9.8/10.3 0.2/ 0.8 0.2/ 0.8 2-3 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
-------- --------- --------- --------- ------- --------
29/02 PM 10.5/11.0 1.0/ 1.5 0.2/ 0.8 2 None
30/02 AM 12.0/12.5 2.5/ 3.0 0.7/ 1.1 3 Minor
30/03 PM 10.4/10.9 0.9/ 1.4 0.5/ 1.0 3-4 None
01/03 AM 11.2/11.7 1.7/ 2.2 0.2/ 0.8 3 Minor
01/04 PM 9.5/10.0 0.0/ 0.5 0.1/ 0.6 2 None
02/04 AM 10.6/11.1 1.1/ 1.6 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
-------- --------- --------- --------- ------- --------
29/02 PM 10.9/11.4 1.0/ 1.5 0.2/ 0.8 1 None
30/02 AM 12.5/13.0 2.6/ 3.1 0.8/ 1.3 1 Minor
30/03 PM 10.7/11.2 0.8/ 1.3 0.5/ 1.0 2 None
01/03 AM 11.6/12.1 1.7/ 2.2 0.2/ 0.8 2 None
01/04 PM 9.9/10.4 0.0/ 0.5 0.2/ 0.7 1 None
02/04 AM 11.0/11.5 1.1/ 1.6 0.2/ 0.8 1 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
-------- --------- --------- --------- ------- --------
29/02 PM 11.0/11.5 0.9/ 1.4 0.2/ 0.8 1 None
30/02 AM 12.5/13.0 2.3/ 2.8 0.7/ 1.1 1-2 Minor
30/03 PM 10.8/11.3 0.7/ 1.1 0.5/ 1.0 2 None
01/03 AM 11.7/12.2 1.6/ 2.0 0.2/ 0.8 2 None
01/04 PM 10.0/10.5 -0.2/ 0.3 0.2/ 0.7 2 None
02/04 AM 11.0/11.5 0.9/ 1.4 0.2/ 0.7 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
-------- --------- --------- --------- ------- --------
29/02 PM 10.4/10.9 0.7/ 1.1 0.2/ 0.8 2 None
30/02 AM 12.2/12.7 2.5/ 3.0 0.8/ 1.3 2-3 Minor
30/03 PM 10.4/10.9 0.7/ 1.1 0.6/ 1.1 3-4 None
01/03 AM 11.5/12.0 1.8/ 2.2 0.4/ 0.9 3-4 Minor
01/04 PM 9.7/10.2 0.0/ 0.5 0.2/ 0.8 2 None
02/04 AM 11.0/11.5 1.3/ 1.8 0.4/ 0.9 2-3 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
-------- --------- --------- --------- ------- --------
29/03 PM 4.5/ 5.0 0.0/ 0.5 0.6/ 1.1 1 None
30/03 AM 6.2/ 6.7 1.7/ 2.2 1.2/ 1.7 2-3 None
30/04 PM 4.6/ 5.1 0.1/ 0.6 0.8/ 1.3 3 None
01/04 AM 5.2/ 5.7 0.8/ 1.3 0.4/ 0.9 3 None
01/05 PM 4.0/ 4.5 -0.6/-0.1 0.2/ 0.8 2 None
02/05 AM 5.2/ 5.7 0.7/ 1.1 0.5/ 1.0 2-3 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
-------- --------- --------- --------- ------- --------
29/11 PM 6.1/ 6.6 1.7/ 2.2 0.9/ 1.4 1-2 Minor
30/12 PM 4.7/ 5.2 0.4/ 0.9 0.7/ 1.1 2-3 None
01/12 AM 5.2/ 5.7 0.8/ 1.3 0.2/ 0.8 3 None
01/12 PM 4.0/ 4.5 -0.3/ 0.2 0.1/ 0.6 1 None
02/01 AM 5.0/ 5.5 0.6/ 1.1 0.5/ 1.0 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
-------- --------- --------- --------- ------- --------
29/02 PM 10.9/11.4 0.8/ 1.3 0.2/ 0.8 1 None
30/02 AM 12.7/13.2 2.6/ 3.1 0.9/ 1.4 1-2 Minor
30/03 PM 10.9/11.4 0.8/ 1.3 0.7/ 1.1 2-3 None
01/03 AM 11.9/12.4 1.8/ 2.2 0.5/ 1.0 3 None
01/04 PM 10.0/10.5 -0.2/ 0.3 0.2/ 0.7 1 None
02/04 AM 11.3/11.8 1.2/ 1.7 0.4/ 0.9 1 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
-------- --------- --------- --------- ------- --------
29/11 PM 3.9/ 4.4 1.9/ 2.3 0.8/ 1.3 1-2 None
30/12 PM 2.7/ 3.2 0.7/ 1.1 0.2/ 0.8 2-3 None
01/12 AM 2.8/ 3.4 0.9/ 1.4 0.0/ 0.5 3 None
01/01 PM 2.3/ 2.8 0.4/ 0.9 0.1/ 0.6 1 None
02/01 AM 2.7/ 3.2 0.8/ 1.3 0.2/ 0.7 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
-------- --------- --------- --------- ------- --------
29/02 PM 11.6/12.1 1.1/ 1.6 0.5/ 1.0 1 None
30/02 AM 13.3/13.8 2.7/ 3.2 0.9/ 1.4 1-2 Minor
30/03 PM 11.7/12.2 1.2/ 1.7 0.9/ 1.4 2-3 None
01/03 AM 12.7/13.2 2.2/ 2.7 0.6/ 1.1 3 Minor
01/04 PM 10.7/11.2 0.2/ 0.7 0.2/ 0.8 1-2 None
02/04 AM 12.0/12.5 1.5/ 2.0 0.5/ 1.0 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
-------- --------- --------- --------- ------- --------
29/03 PM 5.0/ 5.5 -2.7/-2.2 0.1/ 0.6 2 None
30/03 AM 6.7/ 7.2 -1.1/-0.6 0.8/ 1.3 3-4 None
30/04 PM 5.5/ 6.0 -2.2/-1.8 0.8/ 1.3 3 None
01/04 AM 6.2/ 6.8 -1.5/-1.0 0.6/ 1.1 3 None
01/05 PM 4.7/ 5.2 -3.0/-2.5 0.2/ 0.8 2-3 None
02/05 AM 6.0/ 6.5 -1.8/-1.3 0.5/ 1.0 3-4 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
-------- --------- --------- --------- ------- --------
29/02 PM 9.8/10.3 -0.6/-0.1 0.4/ 0.9 1-2 None
30/02 AM 11.5/12.0 1.2/ 1.7 0.9/ 1.4 1-2 None
30/03 PM 9.8/10.3 -0.6/-0.1 0.7/ 1.1 2-3 None
01/03 AM 10.8/11.3 0.5/ 1.0 0.5/ 1.0 3 None
01/04 PM 9.0/ 9.5 -1.4/-0.9 0.2/ 0.8 1-2 None
02/04 AM 10.2/10.7 -0.2/ 0.3 0.4/ 0.9 1-2 None
&&
$$
FrankThe office that day
Everything else NWS Boston/Norton, MA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 29, 4:28 AM EDT | Gale Watch | BOX | 11 hr | |
| Apr 29, 6:41 AM EDT | Dense Fog Advisory | BOX | Barnstable, Dukes, Nantucket | 2 hr |
| Apr 29, 3:24 PM EDT | Wind Advisory | BOX | Barnstable, Bristol, Dukes, Essex, Franklin, Hampden and 7 more | 35 hr |
| Apr 29, 3:32 PM EDT | Gale Warning | BOX | 35 hr |
Nearby
Coastal Flood Statements in Massachusetts, 2021Every coastal flood statement 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.