Alert archive / Massachusetts / Heat Advisories in 2021

Heat Advisory 9, NWS Boston/Norton, MA

August 12, 202111 counties in Massachusetts; 5 counties in Rhode Island; Capitol Planning Region, Northeastern Connecticut Planning Region, Connecticut

NWS Boston/Norton, MA issued this heat advisory at Aug 12, 2021, 2:53 PM EDT for 11 counties in Massachusetts; 5 counties in Rhode Island; Capitol Planning Region, Northeastern Connecticut Planning Region, Connecticut. It took effect at Aug 13, 2021, 11:00 AM EDT. It was in force for 9 hr.

The area

The counties it named.

The facts

Issued
Aug 12, 2021, 2:53 PM EDT (18:53 UTC)
In effect from
Aug 13, 2021, 11:00 AM EDT
Expired
Aug 13, 2021, 8:00 PM EDT
In force
9 hr
Issued by
NWS Boston/Norton, MA

Counties Capitol Planning Region, CT, Northeastern Connecticut Planning Region, CT, Barnstable County, MA, Bristol County, MA, Essex County, MA, Franklin County, MA, Hampden County, MA, Hampshire County, MA, Middlesex 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), 37 km from the middle of the area, began a volume at 18:54 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

Brookhaven, NY (KOKX), launched 12:00Z, 6.9 hours before the alert went out and 167 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, Brookhaven, NY at 12:00Z on 2021-08-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 278 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, Brookhaven, NY at 12:00Z on 2021-08-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -82 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
278 J/kg
Mixed-layer CIN
-162 J/kg
Mixed-layer LCL
1400 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
-82 m²/s²
0-3 km storm-relative helicity
-47 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

450 
WWUS71 KBOX 121853
NPWBOX

URGENT - WEATHER MESSAGE
National Weather Service Boston/Norton MA
253 PM EDT Thu Aug 12 2021

CTZ002>004-MAZ003>007-010>019-026-RIZ001>005-130800-
/O.UPG.KBOX.EH.A.0001.210813T0000Z-210814T0000Z/
/O.NEW.KBOX.HT.Y.0009.210813T1500Z-210814T0000Z/
/O.CON.KBOX.EH.W.0001.000000T0000Z-210813T0000Z/
Hartford CT-Tolland CT-Windham CT-Eastern Franklin MA-
Northern Worcester MA-Central Middlesex MA-Western Essex MA-
Eastern Essex MA-Eastern Hampshire MA-Eastern Hampden MA-
Southern Worcester MA-Western Norfolk MA-Southeast Middlesex MA-
Suffolk MA-Eastern Norfolk MA-Northern Bristol MA-
Western Plymouth MA-Eastern Plymouth MA-Northern Middlesex MA-
Northwest Providence RI-Southeast Providence RI-Western Kent RI-
Eastern Kent RI-Bristol RI-
Including the cities of Hartford, Windsor Locks, Union, Vernon, 
Putnam, Willimantic, Greenfield, Orange, Barre, Fitchburg, 
Framingham, Lowell, Lawrence, Gloucester, Amherst, Northampton, 
Springfield, Milford, Worcester, Foxborough, Norwood, Cambridge, 
Boston, Quincy, Taunton, Brockton, Plymouth, Ayer, Foster, 
Smithfield, Providence, Coventry, West Greenwich, East Greenwich,
Warwick, West Warwick, and Bristol
253 PM EDT Thu Aug 12 2021

...EXCESSIVE HEAT WARNING REMAINS IN EFFECT UNTIL 8 PM EDT THIS
EVENING...
...HEAT ADVISORY IN EFFECT FROM 11 AM TO 8 PM EDT FRIDAY...

* WHAT...For the Excessive Heat Warning, dangerously hot 
  conditions with heat index values up to 105. For the Heat 
  Advisory, heat index values up to 103 expected.

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

* WHEN...For the Excessive Heat Warning, until 8 PM EDT this 
  evening. For the Heat Advisory, from 11 AM to 8 PM EDT Friday.

* IMPACTS...Extreme heat and humidity will significantly 
  increase the potential for heat related illnesses, 
  particularly for those working or participating in outdoor 
  activities.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

MAZ002-008-009-130800-
/O.UPG.KBOX.EH.A.0001.210813T0000Z-210814T0000Z/
/O.NEW.KBOX.HT.Y.0009.210813T1500Z-210814T0000Z/
/O.CON.KBOX.HT.Y.0008.000000T0000Z-210813T0000Z/
Western Franklin MA-Western Hampshire MA-Western Hampden MA-
Including the cities of Charlemont, Chesterfield, and Blandford
253 PM EDT Thu Aug 12 2021

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 8 PM EDT THIS EVENING...
...HEAT ADVISORY IN EFFECT FROM 11 AM TO 8 PM EDT FRIDAY...

* WHAT...For the first Heat Advisory, heat index values up to 
  99. For the second Heat Advisory, heat index values up to 98 
  expected.

* WHERE...Western Franklin MA, Western Hampshire MA and Western 
  Hampden MA Counties.

* WHEN...For the first Heat Advisory, until 8 PM EDT this 
  evening. For the second Heat Advisory, from 11 AM to 8 PM EDT 
  Friday.

* IMPACTS...Hot temperatures and high humidity may cause heat
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

MAZ020-021-RIZ006-007-130800-
/O.NEW.KBOX.HT.Y.0009.210813T1500Z-210814T0000Z/
/O.CON.KBOX.HT.Y.0008.000000T0000Z-210813T0000Z/
Southern Bristol MA-Southern Plymouth MA-Washington RI-Newport RI-
Including the cities of Fall River, New Bedford, Mattapoisett, 
Narragansett, Westerly, and Newport
253 PM EDT Thu Aug 12 2021

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 8 PM EDT THIS EVENING...
...HEAT ADVISORY IN EFFECT FROM 11 AM TO 8 PM EDT FRIDAY...

* WHAT...For the first Heat Advisory, heat index values up to 
  99. For the second Heat Advisory, heat index values up to 101 
  expected.

* WHERE...In Massachusetts, Southern Bristol MA and Southern 
  Plymouth MA Counties. In Rhode Island, Washington RI and 
  Newport RI Counties.

* WHEN...For the first Heat Advisory, until 8 PM EDT this 
  evening. For the second Heat Advisory, from 11 AM to 8 PM EDT 
  Friday.

* IMPACTS...Hot temperatures and high humidity may cause heat
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

MAZ022-130800-
/O.NEW.KBOX.HT.Y.0009.210813T1500Z-210814T0000Z/
Barnstable MA-
Including the cities of Chatham, Falmouth, and Provincetown
253 PM EDT Thu Aug 12 2021

...HEAT ADVISORY IN EFFECT FROM 11 AM TO 8 PM EDT FRIDAY...

* WHAT...Heat index values up to 97 expected.

* WHERE...Barnstable MA County.

* WHEN...From 11 AM to 8 PM EDT Friday.

* IMPACTS...Hot temperatures and high humidity may cause heat
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

For more information from the National Weather Service visit
https://weather.gov/box
2 follow-up statements
705 
WWUS71 KBOX 130716
NPWBOX

URGENT - WEATHER MESSAGE
National Weather Service Boston/Norton MA
316 AM EDT Fri Aug 13 2021

CTZ002>004-MAZ003>007-010>021-026-RIZ001>007-132115-
/O.CON.KBOX.HT.Y.0009.210813T1500Z-210814T0000Z/
Hartford CT-Tolland CT-Windham CT-Eastern Franklin MA-
Northern Worcester MA-Central Middlesex MA-Western Essex MA-
Eastern Essex MA-Eastern Hampshire MA-Eastern Hampden MA-
Southern Worcester MA-Western Norfolk MA-Southeast Middlesex MA-
Suffolk MA-Eastern Norfolk MA-Northern Bristol MA-
Western Plymouth MA-Eastern Plymouth MA-Southern Bristol MA-
Southern Plymouth MA-Northern Middlesex MA-
Northwest Providence RI-Southeast Providence RI-Western Kent RI-
Eastern Kent RI-Bristol RI-Washington RI-Newport RI-
Including the cities of Hartford, Windsor Locks, Union, Vernon, 
Putnam, Willimantic, Greenfield, Orange, Barre, Fitchburg, 
Framingham, Lowell, Lawrence, Gloucester, Amherst, Northampton, 
Springfield, Milford, Worcester, Foxborough, Norwood, Cambridge, 
Boston, Quincy, Taunton, Brockton, Plymouth, Fall River, 
New Bedford, Mattapoisett, Ayer, Foster, Smithfield, Providence, 
Coventry, West Greenwich, East Greenwich, Warwick, West Warwick, 
Bristol, Narragansett, Westerly, and Newport
316 AM EDT Fri Aug 13 2021

...HEAT ADVISORY REMAINS IN EFFECT FROM 11 AM THIS MORNING TO
8 PM EDT THIS EVENING...

* WHAT...Heat index values between 95 and 103 expected.

* WHERE...Most of Southern New England, excluding the eastern 
  slopes of the Berkshires, Cape Cod and the Islands.

* WHEN...From 11 AM this morning to 8 PM EDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

MAZ022-132115-
/O.CON.KBOX.HT.Y.0009.210813T1500Z-210814T0000Z/
Barnstable MA-
Including the cities of Chatham, Falmouth, and Provincetown
316 AM EDT Fri Aug 13 2021

...HEAT ADVISORY REMAINS IN EFFECT FROM 11 AM THIS MORNING TO
8 PM EDT THIS EVENING...

* WHAT...Heat index values up to 96 expected.

* WHERE...Barnstable County.

* WHEN...From 11 AM this morning to 8 PM EDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

MAZ002-008-009-132115-
/O.CON.KBOX.HT.Y.0009.210813T1500Z-210814T0000Z/
Western Franklin MA-Western Hampshire MA-Western Hampden MA-
Including the cities of Charlemont, Chesterfield, and Blandford
316 AM EDT Fri Aug 13 2021

...HEAT ADVISORY REMAINS IN EFFECT FROM 11 AM THIS MORNING TO
8 PM EDT THIS EVENING...

* WHAT...Heat index values up to 95 expected.

* WHERE...The eastern slopes of the Berkshires.

* WHEN...From 11 AM this morning to 8 PM EDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

For more information from the National Weather Service visit
https://weather.gov/box
533 
WWUS71 KBOX 131947
NPWBOX

URGENT - WEATHER MESSAGE
National Weather Service Boston/Norton MA
347 PM EDT Fri Aug 13 2021

CTZ002>004-MAZ003>007-010>021-026-RIZ001>007-140000-
/O.CON.KBOX.HT.Y.0009.000000T0000Z-210814T0000Z/
Hartford CT-Tolland CT-Windham CT-Eastern Franklin MA-
Northern Worcester MA-Central Middlesex MA-Western Essex MA-
Eastern Essex MA-Eastern Hampshire MA-Eastern Hampden MA-
Southern Worcester MA-Western Norfolk MA-Southeast Middlesex MA-
Suffolk MA-Eastern Norfolk MA-Northern Bristol MA-
Western Plymouth MA-Eastern Plymouth MA-Southern Bristol MA-
Southern Plymouth MA-Northern Middlesex MA-
Northwest Providence RI-Southeast Providence RI-Western Kent RI-
Eastern Kent RI-Bristol RI-Washington RI-Newport RI-
Including the cities of Hartford, Windsor Locks, Union, Vernon, 
Putnam, Willimantic, Greenfield, Orange, Barre, Fitchburg, 
Framingham, Lowell, Lawrence, Gloucester, Amherst, Northampton, 
Springfield, Milford, Worcester, Foxborough, Norwood, Cambridge, 
Boston, Quincy, Taunton, Brockton, Plymouth, Fall River, 
New Bedford, Mattapoisett, Ayer, Foster, Smithfield, Providence, 
Coventry, West Greenwich, East Greenwich, Warwick, West Warwick, 
Bristol, Narragansett, Westerly, and Newport
347 PM EDT Fri Aug 13 2021

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 8 PM EDT THIS EVENING...

* WHAT...Heat index values up to 100.

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

* WHEN...Until 8 PM EDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

MAZ022-140000-
/O.CON.KBOX.HT.Y.0009.000000T0000Z-210814T0000Z/
Barnstable MA-
Including the cities of Chatham, Falmouth, and Provincetown
347 PM EDT Fri Aug 13 2021

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 8 PM EDT THIS EVENING...

* WHAT...Heat index values up to 94.

* WHERE...Barnstable MA County.

* WHEN...Until 8 PM EDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

MAZ002-008-009-140000-
/O.CON.KBOX.HT.Y.0009.000000T0000Z-210814T0000Z/
Western Franklin MA-Western Hampshire MA-Western Hampden MA-
Including the cities of Charlemont, Chesterfield, and Blandford
347 PM EDT Fri Aug 13 2021

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 8 PM EDT THIS EVENING...

* WHAT...Heat index values up to 93.

* WHERE...Western Franklin MA, Western Hampshire MA and Western 
  Hampden MA Counties.

* WHEN...Until 8 PM EDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

For more information from the National Weather Service visit
https://weather.gov/box

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 12, 3:45 PM EDTSpecial Weather StatementBOXFranklin, Hampshire60 min
Aug 12, 4:45 PM EDTSpecial Weather StatementBOXFranklin, Hampden, Hampshire60 min
Aug 12, 5:02 PM EDTSevere Thunderstorm WarningBOXFranklin, Hampden, Hampshire58 min
Aug 12, 5:35 PM EDTSevere Thunderstorm WarningBOXHampden, Hampshire, Worcester55 min
Aug 12, 5:42 PM EDTSpecial Weather StatementBOXWorcester48 min
Aug 12, 5:51 PM EDTSevere Thunderstorm Warning Considerable damage threatBOXFranklin, Hampden, Hampshire, Worcester39 min
Aug 12, 6:13 PM EDTSevere Thunderstorm WarningBOXBristol, Hampden, Middlesex, Norfolk, Worcester62 min
Aug 12, 6:52 PM EDTSpecial Marine WarningBOX53 min
Aug 12, 7:14 PM EDTSpecial Weather StatementBOXBristol, Plymouth61 min
Aug 12, 6:26 PM EDTSevere Thunderstorm WarningBOXCapitol Planning Region, Northeastern Connecticut Planning Region49 min

Nearby

Heat Advisories in Massachusetts, 2021Heat Advisories in Rhode Island, 2021Heat Advisories in Connecticut, 2021Every heat advisory 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.