Alert archive / Massachusetts / Coastal Flood Statements in 2021

Coastal Flood Statement 9, NWS Boston/Norton, MA

October 10, 20214 counties in Massachusetts

NWS Boston/Norton, MA issued this coastal flood statement at Oct 10, 2021, 2:55 AM EDT for 4 counties in Massachusetts. It took effect at Oct 10, 2021, 12:00 PM EDT. It was in force for 4 hr.

The area

The counties it named.

The facts

Issued
Oct 10, 2021, 2:55 AM EDT (06:55 UTC)
In effect from
Oct 10, 2021, 12:00 PM EDT
Expired
Oct 10, 2021, 4:00 PM EDT
In force
4 hr
Issued by
NWS Boston/Norton, MA

Counties Essex County, MA, Norfolk County, MA, Plymouth County, MA, Suffolk County, MA

The radar

The Boston radar (KBOX), 40 km from the middle of the area, began a volume at 06:55 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 00:00Z, 6.9 hours before the alert went out and 187 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, Gray, ME at 00:00Z on 2021-10-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1 joules per kilogram.LCLLFCEL10008507005003002001001 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, Gray, ME at 00:00Z on 2021-10-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 27 square meters per square second.1939Sfc1 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
1 J/kg
Mixed-layer CIN
-8 J/kg
Mixed-layer LCL
693 m above ground
0-6 km bulk shear
6 kt
0-1 km storm-relative helicity
27 m²/s²
0-3 km storm-relative helicity
1 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

948 
WHUS41 KBOX 100655
CFWBOX

Coastal Hazard Message
National Weather Service Boston/Norton MA
255 AM EDT Sun Oct 10 2021

MAZ007-015-016-019-102000-
/O.NEW.KBOX.CF.S.0009.211010T1600Z-211010T2000Z/
Eastern Essex MA-Suffolk MA-Eastern Norfolk MA-
Eastern Plymouth MA-
255 AM EDT Sun Oct 10 2021

...COASTAL FLOOD STATEMENT IN EFFECT FROM NOON EDT TODAY THROUGH
THIS AFTERNOON...

* WHAT...Up to one half foot of inundation above ground level 
  expected in low-lying areas near shorelines and tidal 
  waterways (10.2 to 12.1 feet Mean Lower Low Water).

* WHERE...Suffolk MA, Eastern Essex MA, Eastern Norfolk MA and 
  Eastern Plymouth MA Counties.

* WHEN...From noon EDT today through this afternoon.

* IMPACTS...Some water on low lying roads and property.


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 
 --------  ---------  ---------  ---------  -------  --------
 10/03 AM   8.8/ 9.3  -0.8/-0.2   0.0/ 0.5    2-3      None    
 10/03 PM   9.9/10.4   0.4/ 0.9   0.1/ 0.6     3       None    
 11/04 AM   8.6/ 9.1  -1.0/-0.5   0.2/ 0.7    2-3      None    
 11/04 PM   9.8/10.3   0.2/ 0.8   0.2/ 0.7     2       None    
 12/05 AM   8.3/ 8.8  -1.3/-0.8   0.2/ 0.7     2       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 
 --------  ---------  ---------  ---------  -------  --------
 10/03 AM   9.9/10.4   0.4/ 0.9   0.0/ 0.5     3       None    
 10/03 PM  11.0/11.5   1.5/ 2.0   0.1/ 0.6     3       None    
 11/03 AM   9.6/10.1   0.1/ 0.6   0.1/ 0.6     3       None    
 11/04 PM  10.7/11.2   1.2/ 1.7   0.2/ 0.7     3       None    
 12/04 AM   9.3/ 9.8  -0.2/ 0.2   0.2/ 0.7     3       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 
 --------  ---------  ---------  ---------  -------  --------
 10/03 AM  10.4/10.9   0.5/ 1.0   0.1/ 0.6     1       None    
 10/03 PM  11.5/12.0   1.6/ 2.0   0.1/ 0.6     1       None    
 11/03 AM  10.1/10.6   0.2/ 0.7   0.2/ 0.7     1       None    
 11/04 PM  11.4/11.9   1.5/ 2.0   0.2/ 0.8     1       None    
 12/04 AM   9.6/10.1  -0.3/ 0.2   0.2/ 0.7     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 
 --------  ---------  ---------  ---------  -------  --------
 10/03 AM  10.5/11.0   0.4/ 0.9   0.1/ 0.6    1-2      None    
 10/03 PM  11.6/12.1   1.5/ 2.0   0.2/ 0.7     2       None    
 11/03 AM  10.2/10.7   0.1/ 0.6   0.2/ 0.8    1-2      None    
 11/04 PM  11.3/11.8   1.2/ 1.7   0.2/ 0.8     1       None    
 12/04 AM   9.7/10.2  -0.5/ 0.0   0.2/ 0.8     1       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 
 --------  ---------  ---------  ---------  -------  --------
 10/03 AM   9.9/10.4   0.2/ 0.7   0.1/ 0.6     3       None    
 10/03 PM  11.1/11.6   1.4/ 1.9   0.2/ 0.7     3      Minor    
 11/03 AM   9.8/10.3   0.1/ 0.6   0.2/ 0.8    2-3      None    
 11/04 PM  11.0/11.5   1.3/ 1.8   0.2/ 0.8     2       None    
 12/04 AM   9.4/ 9.9  -0.3/ 0.2   0.2/ 0.8     2       None

&&

$$
1 follow-up statement
976 
WHUS41 KBOX 101520
CFWBOX

Coastal Hazard Message
National Weather Service Boston/Norton MA
1120 AM EDT Sun Oct 10 2021

MAZ007-015-016-019-102000-
/O.CON.KBOX.CF.S.0009.211010T1600Z-211010T2000Z/
Eastern Essex MA-Suffolk MA-Eastern Norfolk MA-
Eastern Plymouth MA-
1120 AM EDT Sun Oct 10 2021

...COASTAL FLOOD STATEMENT REMAINS IN EFFECT UNTIL 4 PM EDT THIS
AFTERNOON...

* WHAT...Up to one half foot of inundation above ground level 
  expected in low-lying areas near shorelines and tidal 
  waterways (10.2 to 12.1 feet Mean Lower Low Water).

* WHERE...Suffolk MA, Eastern Essex MA, Eastern Norfolk MA and 
  Eastern Plymouth MA Counties.

* WHEN...Until 4 PM EDT this afternoon.

* IMPACTS...Some water on low lying roads and property.

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 
 --------  ---------  ---------  ---------  -------  --------
 10/03 PM  10.0/10.5   0.5/ 1.0   0.2/ 0.7     1       None    
 11/04 AM   8.8/ 9.3  -0.8/-0.2   0.4/ 0.9     1       None    
 11/04 PM  10.0/10.5   0.5/ 1.0   0.4/ 0.9     1       None    
 12/05 AM   8.4/ 8.9  -1.1/-0.7   0.2/ 0.8     1       None    
 12/05 PM   9.6/10.1   0.1/ 0.6   0.2/ 0.8     1       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 
 --------  ---------  ---------  ---------  -------  --------
 10/03 PM  11.1/11.6   1.6/ 2.0   0.2/ 0.7     3      Minor    
 11/03 AM   9.9/10.4   0.4/ 0.9   0.4/ 0.9     3       None    
 11/04 PM  10.9/11.4   1.4/ 1.9   0.4/ 0.9     3       None    
 12/04 AM   9.5/10.0   0.0/ 0.5   0.4/ 0.9     3       None    
 12/05 PM  10.3/10.8   0.8/ 1.3   0.2/ 0.7     3       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 
 --------  ---------  ---------  ---------  -------  --------
 10/03 PM  11.9/12.4   2.0/ 2.5   0.5/ 1.0     1       None    
 11/03 AM  10.6/11.1   0.7/ 1.1   0.7/ 1.1     1       None    
 11/04 PM  11.8/12.3   1.9/ 2.3   0.7/ 1.1     1       None    
 12/04 AM  10.1/10.6   0.2/ 0.7   0.7/ 1.1     1       None    
 12/05 PM  11.1/11.6   1.2/ 1.7   0.5/ 1.0     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 
 --------  ---------  ---------  ---------  -------  --------
 10/03 PM  11.9/12.4   1.8/ 2.2   0.5/ 1.0     2       None    
 11/03 AM  10.6/11.1   0.5/ 1.0   0.7/ 1.1     2       None    
 11/04 PM  11.7/12.2   1.6/ 2.0   0.7/ 1.1     2       None    
 12/04 AM  10.1/10.6   0.0/ 0.5   0.7/ 1.1     1       None    
 12/05 PM  11.1/11.6   1.0/ 1.5   0.5/ 1.0     1       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 
 --------  ---------  ---------  ---------  -------  --------
 10/03 PM  11.3/11.8   1.6/ 2.0   0.4/ 0.9     3      Minor    
 11/03 AM  10.0/10.5   0.2/ 0.8   0.5/ 1.0     3       None    
 11/04 PM  11.2/11.7   1.5/ 2.0   0.5/ 1.0     3      Minor    
 12/04 AM   9.6/10.1  -0.2/ 0.3   0.5/ 1.0    2-3      None    
 12/05 PM  10.6/11.1   0.9/ 1.4   0.2/ 0.8     2       None

&&

$$

The office that day

Everything else NWS Boston/Norton, MA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Oct 10, 3:21 PM EDTSmall Craft AdvisoryBOX43 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.