Alert archive / Massachusetts / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 20, NWS Boston/Norton, MA

June 6, 20204 counties in Massachusetts

NWS Boston/Norton, MA issued this severe thunderstorm warning at Jun 6, 2020, 2:15 PM EDT for 4 counties in Massachusetts. It was in force for 60 min. 6 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Jun 6, 2020, 2:15 PM EDT (18:15 UTC)
Expired
Jun 6, 2020, 3:15 PM EDT
In force
60 min
Issued by
NWS Boston/Norton, MA
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Franklin County, MA, Hampden County, MA, Hampshire County, MA, Worcester County, MA

The radar

The Boston radar (KBOX), 79 km from the middle of the area, began a volume at 18:19 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.

What was reported inside it

TimeReportWhereRemark
Jun 6, 2:25 PM EDTTSTM WND DMGWest Brookfield, MATREE DOWN ON BIRCH HILL RD
Jun 6, 2:40 PM EDTTSTM WND DMGSturbridge, MATREE AND WIRES DOWN
Jun 6, 2:44 PM EDTTSTM WND DMGSpencer, MATREE DOWN ON NORTHWEST RD
Jun 6, 2:46 PM EDTTSTM WND DMG3 Nnw Oxford, MAPOWER POLE DOWN AND LEANING ON WIRES ON OAK ST IN OXFORD.
Jun 6, 3:02 PM EDTTSTM WND DMGAuburn, MAWIRES DOWN ON SOUTH ST
Jun 6, 3:02 PM EDTTSTM WND DMGOxford, MAWIRES DOWN ON SUTTON AVE

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

Did it verify

Verified. The Iowa Environmental Mesonet's Cow matched 6 storm reports to this severe thunderstorm warning; the first came 10 minutes after it went out.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Jun 6, 12:23 PM EDTSevere Thunderstorm WatchSPC8 hr

The nearest sounding before it

Albany, NY (KALY), launched 12:00Z, 6.3 hours before the alert went out and 158 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, Albany, NY at 12:00Z on 2020-06-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 198 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Albany, NY at 12:00Z on 2020-06-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 41 square meters per square second.19395878Sfc1 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
198 J/kg
Mixed-layer CIN
-82 J/kg
Mixed-layer LCL
1045 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
41 m²/s²
0-3 km storm-relative helicity
93 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

As transmitted.

591 
WUUS51 KBOX 061815
SVRBOX
MAC011-013-015-027-061915-
/O.NEW.KBOX.SV.W.0020.200606T1815Z-200606T1915Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Boston/Norton MA
215 PM EDT Sat Jun 6 2020

The National Weather Service in Boston/Norton has issued a

* Severe Thunderstorm Warning for...
  Southwestern Worcester County in central Massachusetts...
  Southeastern Hampshire County in western Massachusetts...
  Southeastern Franklin County in western Massachusetts...
  Southeastern Hampden County in western Massachusetts...

* Until 315 PM EDT.

* At 215 PM EDT, a severe thunderstorm was located over Palmer, or 11
  miles east of Springfield, moving east at 25 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Expect wind damage to trees and power lines. Minor hail 
           damage to vehicles is possible.

* Locations impacted include...
  Worcester, Shrewsbury, Ludlow, Grafton, Holden, Webster,
  Southbridge, Auburn, Belchertown, Wilbraham, Oxford, Millbury,
  Charlton, Palmer, Spencer, Dudley, Leicester, Ware, Thompson and
  Sturbridge.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Large hail and damaging winds and continuous cloud to ground
lightning is occurring with this storm. Move indoors immediately.
Lightning is one of nature's leading killers. Remember, if you can
hear thunder, you are close enough to be struck by lightning.

&&

LAT...LON 4236 7243 4238 7172 4201 7174 4201 7180
      4202 7180 4202 7205 4204 7244
TIME...MOT...LOC 1815Z 275DEG 22KT 4216 7231 

HAIL...1.00IN
WIND...60MPH
 
$$

Loconto
4 follow-up statements
635 
WWUS51 KBOX 061829
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
229 PM EDT Sat Jun 6 2020

MAC011-013-015-027-061915-
/O.CON.KBOX.SV.W.0020.000000T0000Z-200606T1915Z/
Worcester MA-Hampshire MA-Franklin MA-Hampden MA-
229 PM EDT Sat Jun 6 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 315 PM EDT
FOR SOUTHWESTERN WORCESTER...SOUTHEASTERN HAMPSHIRE...SOUTHEASTERN
FRANKLIN AND SOUTHEASTERN HAMPDEN COUNTIES...

At 228 PM EDT, a severe thunderstorm was located over Brimfield, or
17 miles east of Springfield, moving east at 25 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated. At 225 PM, a tree was downed in West 
         Brookfield.

IMPACT...Expect wind damage to trees and power lines. Minor hail 
         damage to vehicles is possible.

Locations impacted include...
Worcester, Shrewsbury, Ludlow, Grafton, Holden, Webster, Southbridge,
Auburn, Belchertown, Wilbraham, Oxford, Millbury, Charlton, Palmer,
Spencer, Dudley, Leicester, Ware, Thompson and Sturbridge.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

&&

LAT...LON 4233 7242 4238 7172 4201 7174 4201 7180
      4202 7180 4202 7205 4204 7244
TIME...MOT...LOC 1828Z 275DEG 22KT 4215 7220 

TORNADO...POSSIBLE
HAIL...1.00IN
WIND...60MPH
 
$$

Loconto
024 
WWUS51 KBOX 061843
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
243 PM EDT Sat Jun 6 2020

MAC011-015-061853-
/O.CAN.KBOX.SV.W.0020.000000T0000Z-200606T1915Z/
Hampshire MA-Franklin MA-
243 PM EDT Sat Jun 6 2020

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN HAMPSHIRE AND
SOUTHEASTERN FRANKLIN COUNTIES IS CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 800 PM EDT for
northern Connecticut...western and central Massachusetts...and Rhode
Island.

LAT...LON 4217 7228 4235 7212 4238 7172 4201 7174
      4201 7180 4202 7180 4202 7205 4204 7244
TIME...MOT...LOC 1843Z 270DEG 26KT 4217 7197 

$$

MAC013-027-061915-
/O.CON.KBOX.SV.W.0020.000000T0000Z-200606T1915Z/
Worcester MA-Hampden MA-
243 PM EDT Sat Jun 6 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 315 PM EDT
FOR SOUTHWESTERN WORCESTER AND SOUTHEASTERN HAMPDEN COUNTIES...

At 243 PM EDT, a severe thunderstorm was located over Charlton, or 10
miles southwest of Worcester, moving east at 30 mph.

HAZARD...60 mph wind gusts and nickel size hail.

SOURCE...Radar indicated. Trees were downed in West Brookfield and 
         Monson from this storm.

IMPACT...Expect damage to trees and power lines.

Locations impacted include...
Worcester, Shrewsbury, Grafton, Holden, Webster, Southbridge, Auburn,
Oxford, Millbury, Charlton, Palmer, Spencer, Dudley, Leicester,
Thompson, Sturbridge, Sutton, Monson, Douglas and Rutland.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4217 7228 4235 7212 4238 7172 4201 7174
      4201 7180 4202 7180 4202 7205 4204 7244
TIME...MOT...LOC 1843Z 270DEG 26KT 4217 7197 

HAIL...0.88IN
WIND...60MPH
 
$$

Loconto
277 
WWUS51 KBOX 061857
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
257 PM EDT Sat Jun 6 2020

MAC013-027-061915-
/O.CON.KBOX.SV.W.0020.000000T0000Z-200606T1915Z/
Worcester MA-Hampden MA-
257 PM EDT Sat Jun 6 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 315 PM EDT
FOR SOUTH CENTRAL WORCESTER AND EASTERN HAMPDEN COUNTIES...

At 256 PM EDT, a severe thunderstorm was located over Oxford, or 7
miles south of Worcester, moving east at 25 mph.

HAZARD...60 mph wind gusts and nickel size hail.

SOURCE...Radar indicated. This storm has a history of producing tree 
         and powerline damage in Brookfield, Spencer, and Monson.

IMPACT...Expect damage to trees and power lines.

Locations impacted include...
Worcester, Shrewsbury, Holden, Webster, Southbridge, Auburn, Oxford,
Millbury, Charlton, Spencer, Dudley, Leicester, Thompson, Sturbridge,
Sutton, Douglas, Woodstock, Paxton, North Brookfield and Holland.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4215 7207 4231 7202 4230 7173 4201 7174
      4201 7180 4202 7180 4202 7205 4203 7219
TIME...MOT...LOC 1856Z 275DEG 22KT 4216 7186 

HAIL...0.88IN
WIND...60MPH
 
$$

Loconto
673 
WWUS51 KBOX 061906
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
306 PM EDT Sat Jun 6 2020

MAC013-027-061915-
/O.EXP.KBOX.SV.W.0020.000000T0000Z-200606T1915Z/
Worcester MA-Hampden MA-
306 PM EDT Sat Jun 6 2020

...THE SEVERE THUNDERSTORM WARNING FOR SOUTH CENTRAL WORCESTER AND
EASTERN HAMPDEN COUNTIES WILL EXPIRE AT 315 PM EDT...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning will be allowed to expire. 

A Severe Thunderstorm Watch remains in effect until 800 PM EDT for
northern Connecticut...western and central Massachusetts...and Rhode
Island.

Remember, a Severe Thunderstorm Warning still remains in effect for
east-central Worcester County until 345 PM.

LAT...LON 4215 7207 4231 7202 4230 7173 4201 7174
      4201 7180 4202 7180 4202 7205 4203 7219
TIME...MOT...LOC 1905Z 275DEG 22KT 4216 7183 

$$

Loconto

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Boston/Norton, MA wrote its last area forecast discussion before this severe thunderstorm warning went out at Jun 6, 10:47 AM EDT, 3 hours 28 minutes earlier.

Area forecast discussion, Jun 6, 10:47 AM EDT, 3 hours 28 minutes before
Area Forecast Discussion
National Weather Service Boston/Norton MA
1047 AM EDT Sat Jun 6 2020

.SYNOPSIS...
A very warm and humid day is in on tap for today and while most of
the day will be dry, the potential exists for a few strong to severe
thunderstorms this afternoon into early this evening as a cold front
crosses the region. Much cooler and less humid air invades the
region tonight and Sunday along with a few showers on Sunday, but
not expecting a washout. High pressure results in pleasant
weather with low humidity continuing Monday. High pressure
remains parked over the northeast into mid week, this will
return us to a period of dry and gradually warmer temperatures.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1047 AM update...

No major changes to the forecast this morning. Continuing to
monitor the breakup of the morning stratus. Expecting it will
take a few more hours across the Cape and islands based on
satellite trends.

Latest mesoscale analysis already showed an impressive amount of
CAPE over our region, between 1,500-2,000 J/kg. Mid level lapse
rates remained barely moist-adiabatic, which is not favorable
for widespread strong convection. That doesn't mean that that a
few thunderstorms cannot become strong to severe later today.
Damaging straight-line wind will be the primary threat.

Regional radars showed showers already starting to develop
across eastern NY state. These were associated with a pre-
frontal trough, which will be one of the convergence mechanisms
available to us today. The other will be a cold front, which
was still farther west across upstate and central NY. Based on
the current timing, this front should be moving across our
region during the time of peak heating.

If you will be outside this afternoon, keep an eye on the sky.
Move indoors if you can see lightning or hear thunder from your
location.

Previous Discussion...

* Very Warm & Humid Today

* A few strong to severe thunderstorms possible this afternoon/early
  evening with the best chance towards the I-95 corridor

A modest southwest low level jet coupled with Pwats near 2 inches
was resulting in showers across RI and SE MA with brief heavy rain.
An embedded t-storm or two is also possible in this region early
this morning given SPC Meso-Analysis page indicates MUcapes around
1000 J/KG. This activity should exit the Cape/Islands by mid to late
morning as the core of the LLJ shifts offshore.

Across the rest of the region, most of the morning will be dry and
partial sunshine should develop. This combined with 925 MB temps
between +21C to +22C should yield afternoon high temperatures in the
upper 80s to near 90 today away from the south coast. It will be
quite humid too with dewpoints well into the 60s. The marine
influence near the south coast will keep highs in the 70s to near
80, but it still will be muggy.

Main concern revolves around the risk for a few strong to severe
thunderstorms this afternoon/early evening with an approaching cold
front. Given ample surface heating and relatively high dewpoints,
expect 1500-2000+ J/KG of Cape to develop across much of the region.
This coupled with effective bulk shear between 40-50 knots are
certainly favorable ingredients. As usual things are not cut and dry
in New England and limiting factors are poor mid level lapse rates
and perhaps a bit too much mid level dry air.

Putting things all together, a severe weather outbreak is not
expected this afternoon. That being said, modest instability & 40-50
knots of effective bulk shear will bring the potential for a few
strong to severe thunderstorms. Areal coverage remains uncertain
given amount of mid level dry air, but appears areal coverage may
increase towards the I-95 corridor where the best
instability/forcing resides.

The main risk will be localized strong to damaging wind gusts given
steep low level lapse rates and DCapes over 800 J/KG. Brief
torrential rainfall may result in very localized street flooding
with the strongest thunderstorms. The main timeframe appears to be
between 1 and 7 PM this evening with the highest risk near the I-95
corridor where forcing/instability is maximized.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
* Much cooler/less humid Tonight and Sunday

Tonight...

A few lingering showers/t-storms should exit the far southeast New
England coast behind the cold front by early-mid evening. This will
also get rid of the remaining fog near the southeast New England
coast during the first part of the evening. Otherwise, mainly a dry
night is expected with a cooler and much less humid airmass invading
the region. Vigorous upper level energy will be dropping down from
the northwest overnight. This should result in an increase in clouds
especially across eastern New England toward daybreak. Low
temperatures by daybreak will be in the middle 50s to the lower 60s.

Sunday...

A much cooler/less humid day is in store for the region with a
scattered to broken deck of mid level cloudiness. NE winds along the
coast should hold high temperatures in the 60s along the immediate
eastern MA coast, Cape and Islands. Across the rest of the region
afternoon highs will generally be between 70 and 75. Dewpoints will
drop into the 45 to 50 degree range, so it will feel much more
comfortable outdoors.

Given the vigorous shortwave energy and 500T near -20C we still will
generate a few hundred J/KG of Cape. The result will be isolated to
scattered showers developing mainly east of the CT River Valley and
we can not rule out the low risk for a rumble or two of thunder. Not
expecting the entire day to be a washout, but some may have to dodge
a few passing showers.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
Highlights...

* Dry and seasonable early next week then warming up

* Next chance of rain comes toward Friday

Details...

Sunday night...

By Sunday night the shortwave moves offshore taking the low
level/mid level moisture with it. As such, cloudcover continues to
clear out through the evening into the overnight hours. A very
relaxed pressure gradient means winds should decouple away from the
urban centers, which will allow for some good radiational cooling.
Temps will fall into the low 50s, right around normal for early
June.

Monday Through Wednesday...

It continues to look like we're in for a very nice stretch of
weather during most of the coming week. Sfc high pressure moves from
the Great Lakes into New England with a building ridge of high
pressure upstream. Subsidence keeps things dry while the cooler air
we enjoyed beneath the trough lingers on Monday, moderating through
mid week. 850 mb temps around 10C on Monday increase to 16C by
Wednesday allowing for highs increasing from the 70s to the mid 80s
respectively. Dewpoints begin low, so Monday and Tuesday will be dry
and comfortable while humidity increases once again on Wednesday.

Thursday and Friday...

The pattern breaks down sometime around Friday bringing increasing
rain chances. Details will depend on how several systems interact,
one being the remnant of Cristobal which should phase with northern
stream energy by mid week, as well as an ocean system off the
Atlantic coast that may be pulled into the flow around New England.

&&

.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
Forecaster Confidence Levels...

Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.

Today...High confidence in trends. Moderate confidence in
timing. MVFR-IFR ceilings will improve to mainly VFR by late
morning inland from the south coast. Areas near the south coast
should see slower improvement as lower clouds/fog may hang
around for much of the day. SW winds of 10 to 15 knots with
some lower 20 knot gusts this afternoon.

While most of the region improves to VFR by late morning, there
is the potential for a few strong thunderstorms this afternoon,
especially towards the I-95 corridor. Areal coverage and
intensity remains somewhat uncertain, but the main time frame of
concern is between 17z and 22z. Brief torrential rainfall and
localized gusty winds are possible with the activity.

Tonight...High Confidence.
A few lingering showers/t-storms will exit the southeast New
England coast by early-mid evening. Otherwise...VFR conditions
except for some lower clouds/fog mainly during the evening
across the Cape/Islands. N winds of 5 to 15 knots.

Sunday...Moderate to high confidence.
A scattered to broken deck of mainly low end VFR but some marginal
MVFR cigs are possible mainly across central/eastern MA and RI
during the morning. A few showers are also possible mainly east of
the CT River Valley, but a washout is not expected. N to NE winds of
5 to 15 knots.

KBOS Terminal...Moderate to high confidence in TAF. Greatest
risk for a thunderstorm near the terminal is between 18z and
21z.

KBDL Terminal...Moderate to high confidence in TAF. Greatest
risk for a thunderstorm near the terminal is between 17z and
20z.

Outlook /Sunday Night through Wednesday/...

Sunday Night through Tuesday Night: VFR.

Wednesday: VFR. Breezy.

&&

.MARINE...
Today...High confidence. Canceled the remaining Small Craft
Advisories across the southern outer coastal waters. Expecting
seas to remain 4 feet or less with SW winds up to 20 kt. Areas
of fog will also be a concern for mariners. Main issue will be
the risk for a few strong thunderstorms late this afternoon/early
this evening as a cold front approaches the region. Winds and
seas will be locally higher in and near thunderstorms.

Tonight and Sunday...High confidence. Any left over showers/t-storms
come to an end by early-mid evening. Fog may also reduce vsbys for
mariners across our southern waters this evening, but that should
lift behind the cold frontal passage. Otherwise, N winds of 10 to 15
knots with some gusts between 20 and 25 Sun morning and early
afternoon across our eastern waters. This should also result in a
period of 3-6 foot seas across our eastern waters, which will likely
require a Small Craft Advisory headline.

Outlook /Sunday Night through Wednesday/...

Sunday Night through Monday: Winds less than 25 kt. Areas of
seas approaching 5 ft.

Monday Night: Winds less than 25 kt. Seas locally approaching
5 ft.

Tuesday: Winds less than 25 kt.

Tuesday Night through Wednesday: Winds less than 25 kt. Seas
locally approaching 5 ft.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...None.

&&

SYNOPSIS...Frank/BW
NEAR TERM...Belk/Frank/BW
SHORT TERM...Frank
LONG TERM...BW
AVIATION...Frank/BW
MARINE...Frank/BW
Hazardous weather outlook, Jun 6, 1:04 PM EDT, 1 hour 11 minutes before
Hazardous Weather Outlook
National Weather Service Boston/Norton MA
104 PM EDT Sat Jun 6 2020

CTZ002>004-MAZ002>021-026-RIZ001>004-071715-
Hartford CT-Tolland CT-Windham CT-Western Franklin MA-
Eastern Franklin MA-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 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-
104 PM EDT Sat Jun 6 2020

...SEVERE THUNDERSTORM WATCH 261 IN EFFECT UNTIL 8 PM EDT THIS
EVENING...

This Hazardous Weather Outlook is for northern Connecticut, central
Massachusetts, eastern Massachusetts, northeastern Massachusetts,
southeastern Massachusetts, western Massachusetts and northern
Rhode Island.

.DAY ONE...This afternoon and tonight.

Strong to severe thunderstorms are possible this afternoon into this
evening. The main threats with any storms are damaging wind gusts,
large hail, frequent lightning and heavy downpours.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions.

MAZ022>024-RIZ005>008-071715-
Barnstable MA-Dukes MA-Nantucket MA-Bristol RI-Washington RI-
Newport RI-Block Island RI-
104 PM EDT Sat Jun 6 2020

This Hazardous Weather Outlook is for southeastern Massachusetts,
northern Rhode Island and southern Rhode Island.

.DAY ONE...This afternoon and tonight.

Strong to severe thunderstorms are possible this afternoon into this
evening. The main threats with any storms are damaging wind gusts,
large hail, frequent lightning and heavy downpours.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions.

ANZ231>237-250-254>256-071715-
Cape Cod Bay-Nantucket Sound-Vineyard Sound-Buzzards Bay-
Rhode Island Sound-Narragansett Bay-Block Island Sound-
Coastal waters east of Ipswich Bay and the Stellwagen Bank National
Marine Sanctuary-
Coastal waters from Provincetown MA to Chatham MA to Nantucket MA
out 20 nm-
Coastal Waters extending out to 25 nm South of Marthas Vineyard and
Nantucket-
Coastal Waters from Montauk NY to Marthas Vineyard extending out to
20 nm South of Block Island-
104 PM EDT Sat Jun 6 2020

This Hazardous Weather Outlook is for Massachusetts coastal waters
and Rhode Island coastal waters.

.DAY ONE...This afternoon and tonight.

Strong to severe thunderstorms are possible this afternoon into this
evening. The main threats with any storms are damaging wind gusts,
large hail, cloud to water lightning, locally higher waves and heavy
downpours.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions.

ANZ230-251-071715-
Boston Harbor-Massachusetts Bay and Ipswich Bay-
104 PM EDT Sat Jun 6 2020

...SEVERE THUNDERSTORM WATCH 261 IN EFFECT UNTIL 8 PM EDT THIS
EVENING...

This Hazardous Weather Outlook is for Massachusetts coastal waters.

.DAY ONE...This afternoon and tonight.

Strong to severe thunderstorms are possible this afternoon into this
evening. The main threats with any storms are damaging wind gusts,
large hail, frequent cloud to water lightning, locally higher waves
and heavy downpours.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions.

For more information on upcoming hazardous weather, please see the
Area Forecast Discussion on our webpage for the latest forecast
thinking. There is also our Enhanced Hazardous Weather Outlook at
www.weather.gov/box/ehwo

For the latest updates...please visit our webpage at
www.weather.gov/boston

You can follow us on Facebook at
www.facebook.com/us.nationalweatherservice.boston.gov

You can follow us on Twitter at
@NWSBoston

In the hours before

Special weather statement, Jun 6, 12:51 PM EDT, 1 hour 24 minutes before
Special Weather Statement
National Weather Service Boston/Norton MA
1251 PM EDT Sat Jun 6 2020

MAZ002-003-008>011-061730-
Western Franklin MA-Western Hampshire MA-Western Hampden MA-
Eastern Hampden MA-Eastern Franklin MA-Eastern Hampshire MA-
1251 PM EDT Sat Jun 6 2020

...A LINE OF STRONG THUNDERSTORMS MOVING ACROSS THE BERKSHIRES INTO
THE CONNECTICUT RIVER VALLEY...

At 1249 PM EDT, Doppler radar was tracking strong thunderstorms along
a line extending from near East Windsor to 6 miles west of Otis.
Movement was east at 35 mph.

Pea size hail and winds in excess of 40 mph will accompany these
storms. Heavy downpours and occasional cloud to ground lightning can
also be expected.

Locations impacted include...
Springfield, Chicopee, Westfield, Holyoke, Amherst, Northampton,
Agawam, West Springfield, Orange, Deerfield, Ludlow, South Hadley,
Easthampton, Longmeadow, East Longmeadow, Belchertown, Southwick,
Montague, Granby and Southampton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Get indoors when these storms approach. Winds may be strong enough to
produce minor damage, such as a few downed branches.

These storms may intensify and become capable of producing damage.
Stay tuned for updated statements and possible warnings.

&&

LAT...LON 4215 7303 4227 7300 4231 7300 4231 7303
      4233 7306 4238 7307 4239 7305 4238 7301
      4239 7301 4257 7297 4257 7234 4205 7253
      4211 7307 4215 7307
TIME...MOT...LOC 1649Z 276DEG 32KT 4247 7310 4223 7319

Loconto
Special weather statement, Jun 6, 1:22 PM EDT, 53 minutes before
Special Weather Statement
National Weather Service Boston/Norton MA
122 PM EDT Sat Jun 6 2020

MAZ003-004-008>011-061815-
Western Hampshire MA-Western Hampden MA-Eastern Hampden MA-
Eastern Franklin MA-Northern Worcester MA-Eastern Hampshire MA-
122 PM EDT Sat Jun 6 2020

...STRONG THUNDERSTORM MOVING INTO THE CONNECTICUT RIVER VALLEY IN
MASSACHUSETTS...

At 121 PM EDT, Doppler radar was tracking a strong thunderstorm near
Huntington, or 11 miles west of Northampton, moving east at 35 mph.

Pea size hail and winds in excess of 40 mph will accompany this
storm.

Locations impacted include...
Springfield, Chicopee, Westfield, Holyoke, Amherst, Northampton,
Ludlow, South Hadley, Easthampton, Belchertown, Wilbraham, Palmer,
Ware, Monson, Granby, Southampton, Hadley, Hatfield, Hardwick and
Williamsburg.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Get indoors when this storm approaches. Winds may be strong enough to
produce minor damage, such as a few downed branches.

Frequent lightning was occurring. Lightning can strike far away from
the storm. Go inside a building or vehicle. Wait at least 30 minutes
until after the storm has passed to resume outdoor activities.

These storms may intensify and become capable of producing damage.
Stay tuned for updated statements and possible warnings.

&&

LAT...LON 4238 7304 4238 7301 4242 7300 4241 7227
      4210 7231 4223 7301 4231 7300 4231 7303
      4232 7305
TIME...MOT...LOC 1721Z 275DEG 32KT 4232 7289

Loconto
Special weather statement, Jun 6, 1:25 PM EDT, 50 minutes before
Special Weather Statement
National Weather Service Boston/Norton MA
125 PM EDT Sat Jun 6 2020

MAZ003-004-061815-
Eastern Franklin MA-Northern Worcester MA-
125 PM EDT Sat Jun 6 2020

...STRONG THUNDERSTORM OVER EASTERN FRANKLIN COUNTY...

At 124 PM EDT, Doppler radar was tracking a strong thunderstorm over
Montague, or 7 miles southeast of Greenfield, moving east at 25 mph.

Pea size hail and winds in excess of 40 mph will accompany this
storm.

Locations impacted include...
Orange, Deerfield, Gardner, Athol, Montague, Templeton, Barre,
Hubbardston, Sunderland, Hardwick, Oakham, Leverett, Erving,
Shutesbury, Phillipston, Petersham, New Braintree, New Salem and
Wendell.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Get indoors when this storm approaches. Winds may be strong enough to
produce minor damage, such as a few downed branches.

Frequent lightning was occurring. Lightning can strike far away from
the storm. Go inside a building or vehicle. Wait at least 30 minutes
until after the storm has passed to resume outdoor activities.

&&

A Severe Thunderstorm Watch remains in effect until 800 PM EDT for
western and central Massachusetts.

LAT...LON 4234 7205 4241 7237 4242 7238 4242 7239
      4247 7262 4258 7255 4261 7201
TIME...MOT...LOC 1724Z 277DEG 22KT 4253 7251

BL
Special weather statement, Jun 6, 1:42 PM EDT, 33 minutes before
Special Weather Statement
National Weather Service Boston/Norton MA
142 PM EDT Sat Jun 6 2020

CTZ002-003-MAZ009>011-061830-
Hartford CT-Tolland CT-Western Hampden MA-Eastern Hampden MA-
Eastern Hampshire MA-
142 PM EDT Sat Jun 6 2020

...STRONG THUNDERSTORMS MOVING INTO THE SPRINGFIELD AREA INTO FAR
NORTHERN PARTS OF HARTFORD AND TOLLAND COUNTIES...

At 140 PM EDT, Doppler radar was tracking a strong thunderstorm near
Tolland Massachusetts, or 10 miles west of Westfield. Another strong
thunderstorm was located near Great Barrington. Both of these
storms were moving east at 35 mph.

Pea size hail and winds in excess of 40 mph will accompany this
storm.

Locations impacted include...
Springfield, Chicopee, Enfield, Westfield, Holyoke, Agawam, West
Springfield, Ludlow, Longmeadow, Suffield, East Longmeadow,
Belchertown, Wilbraham, Palmer, Stafford, Somers, Granby, Southwick,
Monson and Southampton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Get indoors when this storm approaches. Winds may be strong enough to
produce minor damage, such as a few downed branches.

These storms may intensify and become capable of producing damage.
Stay tuned for updated statements and possible warnings.

&&

LAT...LON 4212 7306 4213 7307 4215 7307 4215 7303
      4222 7301 4221 7229 4194 7232 4203 7301
      4204 7301 4204 7306 4206 7305 4210 7307
TIME...MOT...LOC 1740Z 275DEG 32KT 4213 7297

Loconto
Special weather statement, Jun 6, 1:51 PM EDT, 24 minutes before
Special Weather Statement
National Weather Service Boston/Norton MA
151 PM EDT Sat Jun 6 2020

MAZ004-010>012-061845-
Southern Worcester MA-Eastern Hampden MA-Northern Worcester MA-
Eastern Hampshire MA-
151 PM EDT Sat Jun 6 2020

...STRONG THUNDERSTORM MOVING INTO SOUTHERN WORCESTER COUNTY...

At 150 PM EDT, Doppler radar was tracking a strong thunderstorm over
Palmer, or 14 miles east of Springfield, moving east at 25 mph.

Pea size hail and winds in excess of 40 mph will accompany this
storm.

Locations impacted include...
Worcester, Shrewsbury, Webster, Southbridge, Auburn, Belchertown,
Oxford, Millbury, Charlton, Palmer, Spencer, Dudley, Leicester, Ware,
Sturbridge, Sutton, Monson, Douglas, Warren and Paxton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Get indoors when this storm approaches. Winds may be strong enough to
produce minor damage, such as a few downed branches.

These storms may intensify and become capable of producing damage.
Stay tuned for updated statements and possible warnings.

&&

LAT...LON 4208 7236 4226 7236 4230 7175 4203 7175
TIME...MOT...LOC 1750Z 270DEG 23KT 4217 7226

Loconto
Special weather statement, Jun 6, 2:09 PM EDT, 6 minutes before
Special Weather Statement
National Weather Service Boston/Norton MA
209 PM EDT Sat Jun 6 2020

MAZ003>005-009>012-061900-
Southern Worcester MA-Western Hampden MA-Central Middlesex County MA-
Eastern Hampden MA-Eastern Franklin MA-Northern Worcester MA-
Eastern Hampshire MA-
209 PM EDT Sat Jun 6 2020

...LINE OF STRONG THUNDERSTORMS MOVING INTO SOUTHERN WORCESTER
COUNTY...

At 209 PM EDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Ware to Ludlow to near West Springfield.
Movement was east at 30 mph.

Pea size hail and wind gusts up to 50 mph will accompany these
storms.

Locations impacted include...
Worcester, Springfield, Chicopee, Westfield, Holyoke, Marlborough,
Shrewsbury, Agawam, West Springfield, Ludlow, Westborough, Grafton,
Holden, Southbridge, Auburn, East Longmeadow, Belchertown, Wilbraham,
Northborough and Oxford.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Get indoors when these storms approach. Winds may be strong enough to
produce minor damage, such as a few downed branches.

Frequent lightning was occurring. Lightning can strike far away from
the storm. Go inside a building or vehicle. Wait at least 30 minutes
until after the storm has passed to resume outdoor activities.

These storms may intensify and become capable of producing damage.
Stay tuned for updated statements and possible warnings.

&&

A Severe Thunderstorm Watch remains in effect until 800 PM EDT for
northern Connecticut...and western, central and northeastern
Massachusetts.

LAT...LON 4214 7294 4218 7257 4238 7230 4235 7152
      4211 7185 4203 7223
TIME...MOT...LOC 1808Z 277DEG 27KT 4232 7228 4218 7248 4216 7268

BL

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 6, 12:51 PM EDTSpecial Weather StatementBOXHampden, Hampshire39 min
Jun 6, 1:22 PM EDTSpecial Weather StatementBOXHampshire53 min
Jun 6, 1:25 PM EDTSpecial Weather StatementBOXFranklin50 min
Jun 6, 1:42 PM EDTSpecial Weather StatementBOXHampden48 min
Jun 6, 1:51 PM EDTSpecial Weather StatementBOXWorcester54 min
Jun 6, 2:09 PM EDTSpecial Weather StatementBOXHampden, Worcester51 min
Jun 6, 2:32 PM EDTSpecial Weather StatementBOXMiddlesex43 min
Jun 6, 2:39 PM EDTSevere Thunderstorm WarningBOXHampden, Worcester66 min
Jun 6, 2:46 PM EDTSpecial Weather StatementBOXEssex44 min
Jun 6, 2:51 PM EDTSevere Thunderstorm WarningBOXBristol, Middlesex, Norfolk, Worcester54 min
Jun 6, 3:02 PM EDTSpecial Marine WarningBOX58 min
Jun 6, 3:05 PM EDTSpecial Weather StatementBOXMiddlesex, Suffolk40 min
Jun 6, 3:29 PM EDTSevere Thunderstorm WarningBOXBristol, Middlesex, Norfolk, Plymouth, Suffolk61 min
Jun 6, 3:34 PM EDTSpecial Marine WarningBOX56 min
Jun 6, 3:35 PM EDTSpecial Marine WarningBOX55 min
Jun 6, 3:45 PM EDTSpecial Marine WarningBOX60 min
Jun 6, 3:51 PM EDTSpecial Marine WarningBOX54 min
Jun 6, 3:56 PM EDTSpecial Weather StatementBOXSuffolk34 min
Jun 6, 4:01 PM EDTSpecial Weather StatementBOXBristol59 min
Jun 6, 4:24 PM EDTSpecial Marine WarningBOX51 min
Jun 6, 4:32 PM EDTSpecial Weather StatementBOXBarnstable, Plymouth43 min
Jun 6, 4:38 PM EDTSpecial Marine WarningBOX37 min
Jun 6, 4:43 PM EDTSpecial Weather StatementBOXBristol47 min
Jun 6, 5:49 PM EDTSpecial Marine WarningBOX41 min
Jun 6, 7:07 PM EDTSpecial Weather StatementBOXMiddlesex38 min

Nearby

Severe Thunderstorm Warnings in Massachusetts, 2020Every severe thunderstorm warning in 2020

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.