Alert archive / Massachusetts / Winter Storm Watches in 2021

Winter Storm Watch 3, NWS Boston/Norton, MA

February 5, 202112 counties in Massachusetts; Capitol Planning Region, Northeastern Connecticut Planning Region, Connecticut; 5 counties in Rhode Island

NWS Boston/Norton, MA issued this winter storm watch at Feb 5, 2021, 3:27 PM EST for 12 counties in Massachusetts; Capitol Planning Region, Northeastern Connecticut Planning Region, Connecticut; 5 counties in Rhode Island. It took effect at Feb 7, 2021, 7:00 AM EST. It was in force for .

The area

The counties it named.

The facts

Issued
Feb 5, 2021, 3:27 PM EST (20:27 UTC)
In effect from
Feb 7, 2021, 7:00 AM EST
Expired
Feb 6, 2021, 3:27 PM EST
In force
Issued by
NWS Boston/Norton, MA

Counties Capitol Planning Region, CT, Northeastern Connecticut Planning Region, CT, Barnstable County, MA, Bristol County, MA, Dukes County, MA, Essex County, MA, Hampden County, MA, Hampshire County, MA, Middlesex County, MA, Nantucket County, MA, Norfolk County, MA, Plymouth County, MA, Suffolk County, MA, Worcester County, MA, Bristol County, RI, Kent County, RI, Newport County, RI, Providence County, RI, Washington County, RI

The radar

The Boston radar (KBOX), 22 km from the middle of the area, began a volume at 20:29 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

Chatham, MA (KCHH), launched 12:00Z, 8.5 hours before the alert went out and 121 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, Chatham, MA at 12:00Z on 2021-02-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Chatham, MA at 12:00Z on 2021-02-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 108 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1311 m above ground
0-6 km bulk shear
51 kt
0-1 km storm-relative helicity
108 m²/s²
0-3 km storm-relative helicity
100 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

952 
WWUS41 KBOX 052027
WSWBOX

URGENT - WINTER WEATHER MESSAGE
National Weather Service Boston/Norton MA
327 PM EST Fri Feb 5 2021

MAZ017>024-RIZ002>008-060600-
/O.NEW.KBOX.WS.A.0003.210207T1200Z-210208T0600Z/
Northern Bristol MA-Western Plymouth MA-Eastern Plymouth MA-
Southern Bristol MA-Southern Plymouth MA-Barnstable MA-Dukes MA-
Nantucket MA-Southeast Providence RI-Western Kent RI-
Eastern Kent RI-Bristol RI-Washington RI-Newport RI-
Block Island RI-
Including the cities of Taunton, Brockton, Plymouth, Fall River, 
New Bedford, Mattapoisett, Chatham, Falmouth, Provincetown, 
Vineyard Haven, Nantucket, Providence, Coventry, West Greenwich, 
East Greenwich, Warwick, West Warwick, Bristol, Narragansett, 
Westerly, Newport, and New Shoreham
327 PM EST Fri Feb 5 2021

...WINTER STORM WATCH IN EFFECT FROM SUNDAY MORNING THROUGH LATE
SUNDAY NIGHT...

* WHAT...Heavy snow possible. Total snow accumulations of 4 to 8 
  inches possible. Winds could gust as high as 40 mph.

* WHERE...Portions of southeastern Massachusetts and northern 
  and southern Rhode Island.

* WHEN...From Sunday morning through late Sunday night.

* IMPACTS...Travel could be very difficult.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$
4 follow-up statements
817 
WWUS41 KBOX 060251
WSWBOX

URGENT - WINTER WEATHER MESSAGE
National Weather Service Boston/Norton MA
951 PM EST Fri Feb 5 2021

MAZ017>024-RIZ002>008-061100-
/O.CON.KBOX.WS.A.0003.210207T1200Z-210208T0600Z/
Northern Bristol MA-Western Plymouth MA-Eastern Plymouth MA-
Southern Bristol MA-Southern Plymouth MA-Barnstable MA-Dukes MA-
Nantucket MA-Southeast Providence RI-Western Kent RI-
Eastern Kent RI-Bristol RI-Washington RI-Newport RI-
Block Island RI-
Including the cities of Taunton, Brockton, Plymouth, Fall River, 
New Bedford, Mattapoisett, Chatham, Falmouth, Provincetown, 
Vineyard Haven, Nantucket, Providence, Coventry, West Greenwich, 
East Greenwich, Warwick, West Warwick, Bristol, Narragansett, 
Westerly, Newport, and New Shoreham
951 PM EST Fri Feb 5 2021

...WINTER STORM WATCH REMAINS IN EFFECT FROM SUNDAY MORNING
THROUGH LATE SUNDAY NIGHT...

* WHAT...Heavy snow possible. Total snow accumulations of 4 to 8 
  inches possible. Winds could gust as high as 40 mph.

* WHERE...Portions of southeastern Massachusetts and northern 
  and southern Rhode Island.

* WHEN...From Sunday morning through late Sunday night.

* IMPACTS...Travel could be very difficult.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$
548 
WWUS41 KBOX 060820
WSWBOX

URGENT - WINTER WEATHER MESSAGE
National Weather Service Boston/Norton MA
320 AM EST Sat Feb 6 2021

MAZ017>023-RIZ002>008-061630-
/O.UPG.KBOX.WS.A.0003.210207T1200Z-210208T0600Z/
/O.NEW.KBOX.WS.W.0003.210207T1200Z-210208T0600Z/
Northern Bristol MA-Western Plymouth MA-Eastern Plymouth MA-
Southern Bristol MA-Southern Plymouth MA-Barnstable MA-Dukes MA-
Southeast Providence RI-Western Kent RI-Eastern Kent RI-
Bristol RI-Washington RI-Newport RI-Block Island RI-
Including the cities of Taunton, Brockton, Plymouth, Fall River, 
New Bedford, Mattapoisett, Chatham, Falmouth, Provincetown, 
Vineyard Haven, Providence, Coventry, West Greenwich, 
East Greenwich, Warwick, West Warwick, Bristol, Narragansett, 
Westerly, Newport, and New Shoreham
320 AM EST Sat Feb 6 2021

...WINTER STORM WARNING IN EFFECT FROM 7 AM SUNDAY TO 1 AM EST
MONDAY...

* WHAT...Heavy wet snow expected. Total snow accumulations of 5 to
  9 inches. Winds gusting as high as 40 mph.

* WHERE...Portions of southeastern Massachusetts as well as
  central and southern Rhode Island.

* WHEN...From 7 AM Sunday to 1 AM EST Monday. Heaviest snow is
  expected Sunday afternoon with 1 to 2 hour snowfall rates
  possible a times.

* IMPACTS...Travel will be very difficult. 

* ADDITIONAL DETAILS...Heavy wet snow may result in the potential
  for some power outages and downed tree limbs.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency. 

&&

$$

CTZ002>004-MAZ004>016-026-RIZ001-061630-
/O.EXA.KBOX.WS.A.0003.210207T1200Z-210208T0600Z/
Hartford CT-Tolland CT-Windham CT-Northern Worcester MA-
Central Middlesex MA-Western Essex MA-Eastern Essex MA-
Western Hampshire MA-Western Hampden MA-Eastern Hampshire MA-
Eastern Hampden MA-Southern Worcester MA-Western Norfolk MA-
Southeast Middlesex MA-Suffolk MA-Eastern Norfolk MA-
Northern Middlesex MA-Northwest Providence RI-
Including the cities of Hartford, Windsor Locks, Union, Vernon, 
Putnam, Willimantic, Barre, Fitchburg, Framingham, Lowell, 
Lawrence, Gloucester, Chesterfield, Blandford, Amherst, 
Northampton, Springfield, Milford, Worcester, Foxborough, 
Norwood, Cambridge, Boston, Quincy, Ayer, Foster, and Smithfield
320 AM EST Sat Feb 6 2021

...WINTER STORM WATCH IN EFFECT FROM SUNDAY MORNING THROUGH LATE
SUNDAY NIGHT...

* WHAT...Heavy snow possible. Total snow accumulations of 4 to 8 
  inches possible.

* WHERE...Portions of northern Connecticut, central, eastern, 
  northeastern and western Massachusetts and northern Rhode 
  Island.

* WHEN...From Sunday morning through late Sunday night. The
  heaviest snow will fall from late Sunday morning into Sunday
  afternoon.

* IMPACTS...Travel could be very difficult.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$

MAZ024-061630-
/O.CON.KBOX.WS.A.0003.210207T1200Z-210208T0600Z/
Nantucket MA-
Including the city of Nantucket
320 AM EST Sat Feb 6 2021

...WINTER STORM WATCH REMAINS IN EFFECT FROM SUNDAY MORNING
THROUGH LATE SUNDAY NIGHT...

* WHAT...Heavy wet snow possible which may mix with rain and sleet
  at times. Total snow accumulations of 4 to 7 inches possible. 
  Winds could gust as high as 50 mph.

* WHERE...Nantucket MA County.

* WHEN...From Sunday morning through late Sunday night.

* IMPACTS...Plan on slippery road conditions. Gusty winds and
  heavy wet snow could bring down tree branches and result in some
  power outages.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$

Frank
825 
WWUS41 KBOX 061609
WSWBOX

URGENT - WINTER WEATHER MESSAGE
National Weather Service Boston/Norton MA
1109 AM EST Sat Feb 6 2021

MAZ017>023-RIZ002>008-070015-
/O.CON.KBOX.WS.W.0003.210207T1200Z-210208T0600Z/
Northern Bristol MA-Western Plymouth MA-Eastern Plymouth MA-
Southern Bristol MA-Southern Plymouth MA-Barnstable MA-Dukes MA-
Southeast Providence RI-Western Kent RI-Eastern Kent RI-
Bristol RI-Washington RI-Newport RI-Block Island RI-
Including the cities of Taunton, Brockton, Plymouth, Fall River, 
New Bedford, Mattapoisett, Chatham, Falmouth, Provincetown, 
Vineyard Haven, Providence, Coventry, West Greenwich, 
East Greenwich, Warwick, West Warwick, Bristol, Narragansett, 
Westerly, Newport, and New Shoreham
1109 AM EST Sat Feb 6 2021

...WINTER STORM WARNING REMAINS IN EFFECT FROM 7 AM SUNDAY TO
1 AM EST MONDAY...

* WHAT...Heavy wet snow expected. Total snow accumulations of 5 
  to 9 inches. Winds gusting as high as 40 mph.

* WHERE...Portions of southeastern Massachusetts as well as 
  central and southern Rhode Island.

* WHEN...From 7 AM Sunday to 1 AM EST Monday. Heaviest snow is 
  expected Sunday afternoon with 1 to 2 hour snowfall rates 
  possible a times.

* IMPACTS...Travel will be very difficult.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency. 

&&

$$

MAZ024-070015-
/O.CON.KBOX.WS.A.0003.210207T1200Z-210208T0600Z/
Nantucket MA-
Including the city of Nantucket
1109 AM EST Sat Feb 6 2021

...WINTER STORM WATCH REMAINS IN EFFECT FROM SUNDAY MORNING
THROUGH LATE SUNDAY NIGHT...

* WHAT...Heavy wet snow possible which may mix with rain and 
  sleet at times. Total snow accumulations of 4 to 7 inches 
  possible. Winds could gust as high as 50 mph.

* WHERE...Nantucket MA County.

* WHEN...From Sunday morning through late Sunday night.

* IMPACTS...Plan on slippery road conditions. Gusty winds and 
  heavy wet snow could bring down tree branches and result in 
  some power outages.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$

CTZ002>004-MAZ004>016-026-RIZ001-070015-
/O.CON.KBOX.WS.A.0003.210207T1200Z-210208T0600Z/
Hartford CT-Tolland CT-Windham CT-Northern Worcester MA-
Central Middlesex MA-Western Essex MA-Eastern Essex MA-
Western Hampshire MA-Western Hampden MA-Eastern Hampshire MA-
Eastern Hampden MA-Southern Worcester MA-Western Norfolk MA-
Southeast Middlesex MA-Suffolk MA-Eastern Norfolk MA-
Northern Middlesex MA-Northwest Providence RI-
Including the cities of Hartford, Windsor Locks, Union, Vernon, 
Putnam, Willimantic, Barre, Fitchburg, Framingham, Lowell, 
Lawrence, Gloucester, Chesterfield, Blandford, Amherst, 
Northampton, Springfield, Milford, Worcester, Foxborough, 
Norwood, Cambridge, Boston, Quincy, Ayer, Foster, and Smithfield
1109 AM EST Sat Feb 6 2021

...WINTER STORM WATCH REMAINS IN EFFECT FROM SUNDAY MORNING
THROUGH LATE SUNDAY NIGHT...

* WHAT...Heavy snow possible. Total snow accumulations of 4 to 8 
  inches possible.

* WHERE...Portions of northern Connecticut, central, eastern, 
  northeastern and western Massachusetts and northern Rhode 
  Island.

* WHEN...From Sunday morning through late Sunday night. The 
  heaviest snow will fall from late Sunday morning into Sunday 
  afternoon.

* IMPACTS...Travel could be very difficult.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$
426 
WWUS41 KBOX 062027
WSWBOX

URGENT - WINTER WEATHER MESSAGE
National Weather Service Boston/Norton MA
327 PM EST Sat Feb 6 2021

MAZ023-RIZ008-070830-
/O.CAN.KBOX.WS.W.0003.210207T1200Z-210208T0600Z/
/O.NEW.KBOX.WW.Y.0008.210207T1200Z-210208T0600Z/
Dukes MA-Block Island RI-
Including the cities of Vineyard Haven and New Shoreham
327 PM EST Sat Feb 6 2021

...WINTER WEATHER ADVISORY IN EFFECT FROM 7 AM SUNDAY TO 1 AM EST
MONDAY...
...WINTER STORM WARNING IS CANCELLED...

* WHAT...Snow expected. Total snow accumulations of up to 6 
  inches. Winds gusting as high as 40 mph.

* WHERE...In Massachusetts, Dukes MA County. In Rhode Island, 
  Block Island RI County.

* WHEN...From 7 AM Sunday to 1 AM EST Monday.

* IMPACTS...Travel could be very difficult.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

&&

$$

CTZ003-004-MAZ004>007-012>016-026-RIZ001-070830-
/O.UPG.KBOX.WS.A.0003.210207T1200Z-210208T0600Z/
/O.EXA.KBOX.WS.W.0003.210207T1200Z-210208T0600Z/
Tolland CT-Windham CT-Northern Worcester MA-Central Middlesex MA-
Western Essex MA-Eastern Essex MA-Southern Worcester MA-
Western Norfolk MA-Southeast Middlesex MA-Suffolk MA-
Eastern Norfolk MA-Northern Middlesex MA-Northwest Providence RI-
Including the cities of Union, Vernon, Putnam, Willimantic, 
Barre, Fitchburg, Framingham, Lowell, Lawrence, Gloucester, 
Milford, Worcester, Foxborough, Norwood, Cambridge, Boston, 
Quincy, Ayer, Foster, and Smithfield
327 PM EST Sat Feb 6 2021

...WINTER STORM WARNING IN EFFECT FROM 7 AM SUNDAY TO 1 AM EST
MONDAY...

* WHAT...Heavy wet snow expected. Total snow accumulations of 5 to
  8 inches.

* WHERE...Portions of northern Connecticut, central, eastern and 
  northeastern Massachusetts and northern Rhode Island.

* WHEN...From 7 AM Sunday to 1 AM EST Monday.

* IMPACTS...Travel could be very difficult.

* ADDITIONAL DETAILS...Rain may mix in at times, especially near
  the immediate coast. Snowfall rates could reach 1 to 2 inches
  per hour at times during the afternoon hours. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency. 

&&

$$

MAZ017>022-RIZ002>007-070830-
/O.CON.KBOX.WS.W.0003.210207T1200Z-210208T0600Z/
Northern Bristol MA-Western Plymouth MA-Eastern Plymouth MA-
Southern Bristol MA-Southern Plymouth MA-Barnstable MA-
Southeast Providence RI-Western Kent RI-Eastern Kent RI-
Bristol RI-Washington RI-Newport RI-
Including the cities of Taunton, Brockton, Plymouth, Fall River, 
New Bedford, Mattapoisett, Chatham, Falmouth, Provincetown, 
Providence, Coventry, West Greenwich, East Greenwich, Warwick, 
West Warwick, Bristol, Narragansett, Westerly, and Newport
327 PM EST Sat Feb 6 2021

...WINTER STORM WARNING REMAINS IN EFFECT FROM 7 AM SUNDAY TO
1 AM EST MONDAY...

* WHAT...Heavy wet snow expected. Total snow accumulations of 5 to
  9 inches, except for the Outer Cape where only 1 to 3 inches of
  snow are expected. Winds gusting as high as 40 mph.

* WHERE...Portions of southeastern Massachusetts as well as 
  central and southern Rhode Island.

* WHEN...From 7 AM Sunday to 1 AM EST Monday. Heaviest snow is 
  expected Sunday afternoon with 1 to 2 hour snowfall rates 
  possible at times.

* IMPACTS...Travel will be very difficult.

* ADDITIONAL DETAILS...Rain may mix in at times, especially near
  the immediate coast and over Cape Cod. The Outer Cape is
  expected to see mostly rain. Snowfall rates could reach 1 to 2
  inches per hour at times during the afternoon hours where mixing
  doesn't occur.
  

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency. 

&&

$$

MAZ024-070830-
/O.UPG.KBOX.WS.A.0003.210207T1200Z-210208T0600Z/
/O.NEW.KBOX.WW.Y.0008.210207T1200Z-210208T0600Z/
Nantucket MA-
Including the city of Nantucket
327 PM EST Sat Feb 6 2021

...WINTER WEATHER ADVISORY IN EFFECT FROM 7 AM SUNDAY TO 1 AM EST
MONDAY...

* WHAT...Wintry mix of rain and snow expected. Total snow 
  accumulations of up to one inch. Winds gusting as high as 50 
  mph.

* WHERE...Nantucket MA County.

* WHEN...From 7 AM Sunday to 1 AM EST Monday.

* IMPACTS...Plan on slippery road conditions. Gusty winds could 
  bring down tree branches.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

&&

$$

CTZ002-MAZ008>011-070830-
/O.UPG.KBOX.WS.A.0003.210207T1200Z-210208T0600Z/
/O.NEW.KBOX.WW.Y.0008.210207T1200Z-210208T0600Z/
Hartford CT-Western Hampshire MA-Western Hampden MA-
Eastern Hampshire MA-Eastern Hampden MA-
Including the cities of Hartford, Windsor Locks, Chesterfield, 
Blandford, Amherst, Northampton, and Springfield
327 PM EST Sat Feb 6 2021

...WINTER WEATHER ADVISORY IN EFFECT FROM 7 AM SUNDAY TO 1 AM EST
MONDAY...

* WHAT...Snow expected. Total snow accumulations of 4 to 6 
  inches.

* WHERE...In Connecticut, Hartford CT County. In Massachusetts, 
  Western Hampshire MA, Western Hampden MA, Eastern Hampshire MA 
  and Eastern Hampden MA Counties.

* WHEN...From 7 AM Sunday to 1 AM EST Monday.

* IMPACTS...Travel could be very difficult.

* ADDITIONAL DETAILS...Snowfall rates could reach 1 to 2 inches
  per hour at times. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

&&

$$

MAZ002-003-070830-
/O.NEW.KBOX.WW.Y.0008.210207T1200Z-210208T0600Z/
Western Franklin MA-Eastern Franklin MA-
Including the cities of Charlemont, Greenfield, and Orange
327 PM EST Sat Feb 6 2021

...WINTER WEATHER ADVISORY IN EFFECT FROM 7 AM SUNDAY TO 1 AM EST
MONDAY...

* WHAT...Snow expected. Total snow accumulations of 4 to 6 
  inches.

* WHERE...Western Franklin MA and Eastern Franklin MA Counties.

* WHEN...From 7 AM Sunday to 1 AM EST Monday.

* IMPACTS...Plan on slippery road conditions.

* ADDITIONAL DETAILS...Snowfall rates could reach 1 to 2 inches
  per hour at times. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

&&

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Feb 5, 3:43 AM ESTGale WatchBOX24 hr
Feb 5, 3:43 AM ESTSmall Craft AdvisoryBOX36 hr

Nearby

Winter Storm Watches in Massachusetts, 2021Winter Storm Watches in Rhode Island, 2021Winter Storm Watches in Connecticut, 2021Every winter storm watch 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.