A cold front pushed into a warm, humid air mass and produced a round of severe thunderstorms in the afternoon across Massachusetts, northeast Connecticut, and northern Rhode Island.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS BOX wrote it up.
A cold front pushed into a warm, humid air mass and produced a round of severe thunderstorms in the afternoon across Massachusetts, northeast Connecticut, and northern Rhode Island.
The local office's own words before the first event, 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 the first event at Jun 6, 9:47 AM EST, 4 hours 51 minutes earlier.
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 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
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
237 PM EDT SAT JUN 06 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0218 PM TSTM WND DMG EAST LONGMEADOW 42.07N 72.52W
06/06/2020 HAMPDEN MA AMATEUR RADIO
TREE AND WIRES DOWN AT COLTON PLACE
0224 PM TSTM WND DMG HOLYOKE 42.21N 72.64W
06/06/2020 HAMPDEN MA AMATEUR RADIO
TREE DOWN ON BROWN AVE
0224 PM TSTM WND DMG HOLYOKE 42.21N 72.64W
06/06/2020 HAMPDEN MA AMATEUR RADIO
TREE DOWN ON JACKSON AT HIGH ST
0224 PM TSTM WND DMG HOLYOKE 42.21N 72.64W
06/06/2020 HAMPDEN MA AMATEUR RADIO
TREE DOWN ON JACKSON AT MAPLE ST
0225 PM TSTM WND DMG WEST BROOKFIELD 42.24N 72.15W
06/06/2020 WORCESTER MA AMATEUR RADIO
TREE DOWN ON BIRCH HILL RD
&&
EVENT NUMBER BOX2001482
EVENT NUMBER BOX2001483
EVENT NUMBER BOX2001484
EVENT NUMBER BOX2001485
EVENT NUMBER BOX2001486
RCSpecial Weather Statement
National Weather Service Boston/Norton MA
243 PM EDT Sat Jun 6 2020
CTZ002-003-MAZ011-061930-
Hartford CT-Tolland CT-Eastern Hampden MA-
243 PM EDT Sat Jun 6 2020
...LINE OF STRONG THUNDERSTORMS APPROACHING HARTFORD COUNTY...
At 242 PM EDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Hartland to Litchfield. Movement was east
at 35 mph.
Pea size hail and winds in excess of 30 mph will accompany these
storms.
Locations impacted include...
Hartford, New Britain, West Hartford, Bristol, East Hartford,
Enfield, Newington, Windsor, South Windsor, Farmington, Simsbury,
Bloomfield, Avon, Plainville, Suffield, Ellington, Windsor Locks,
Stafford, Somers and Granby.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Get indoors when these storms approach. Winds may be strong enough to
produce minor damage, such as a few downed branches.
&&
LAT...LON 4181 7295 4184 7294 4185 7295 4189 7294
4190 7291 4197 7289 4197 7296 4203 7287
4202 7234 4166 7278 4167 7299 4180 7302
TIME...MOT...LOC 1842Z 273DEG 30KT 4197 7290 4175 7322
FieldSpecial Weather Statement
National Weather Service Boston/Norton MA
246 PM EDT Sat Jun 6 2020
MAZ005>007-061930-
Eastern Essex MA-Central Middlesex County MA-Western Essex MA-
246 PM EDT Sat Jun 6 2020
...STRONG THUNDERSTORM MOVING INTO ESSEX COUNTY...
At 246 PM EDT, Doppler radar was tracking a strong thunderstorm over
Pelham, or near Dracut, moving east at 35 mph.
Pea size hail and winds in excess of 40 mph will accompany this
storm.
Locations impacted include...
Lawrence, Haverhill, Methuen, Andover, Dracut, Gloucester, North
Andover, Danvers, Newburyport, Ipswich, Middleton, Georgetown,
Boxford, Hamilton, Rockport, Newbury, Groveland, Topsfield, Rowley
and Manchester.
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.
&&
A Severe Thunderstorm Watch remains in effect until 800 PM EDT for
northeastern Massachusetts.
LAT...LON 4270 7077 4270 7078 4277 7082 4270 7083
4267 7073 4264 7076 4269 7063 4263 7061
4258 7066 4259 7066 4260 7065 4261 7068
4257 7073 4269 7138 4274 7119 4279 7118
4282 7114 4280 7083 4282 7081
TIME...MOT...LOC 1846Z 275DEG 31KT 4273 7126
BLSpecial Weather Statement
National Weather Service Boston/Norton MA
305 PM EDT Sat Jun 6 2020
MAZ005-007-013>015-019-061945-
Eastern Essex MA-Eastern Plymouth MA-Suffolk MA-Western Norfolk MA-
Central Middlesex County MA-Southeast Middlesex MA-
305 PM EDT Sat Jun 6 2020
...STRONG THUNDERSTORM MOVING TOWARD CITY OF BOSTON...
At 305 PM EDT, Doppler radar was tracking a strong thunderstorm over
Maynard, or 7 miles northeast of Marlborough, moving east at 30 mph.
Pea size hail and winds in excess of 40 mph will accompany this
storm.
Locations impacted include...
Boston, Cambridge, Lynn, Newton, Somerville, Framingham, Waltham,
Malden, Brookline, Medford, Revere, Peabody, Arlington, Everett,
Salem, Billerica, Beverly, Marlborough, Woburn and Chelsea.
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.
&&
A Severe Thunderstorm Watch remains in effect until 800 PM EDT for
eastern, central, southeastern and northeastern Massachusetts.
LAT...LON 4256 7088 4247 7088 4246 7094 4242 7091
4243 7092 4241 7099 4234 7088 4233 7089
4236 7095 4229 7088 4238 7100 4230 7090
4233 7096 4231 7102 4233 7103 4230 7105
4233 7155 4249 7154
TIME...MOT...LOC 1903Z 269DEG 26KT 4243 7146
BLPRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
320 PM EDT SAT JUN 06 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0218 PM TSTM WND DMG EAST LONGMEADOW 42.07N 72.52W
06/06/2020 HAMPDEN MA AMATEUR RADIO
TREE AND WIRES DOWN AT COLTON PLACE
0224 PM TSTM WND DMG HOLYOKE 42.21N 72.64W
06/06/2020 HAMPDEN MA AMATEUR RADIO
TREE DOWN ON BROWN AVE
0224 PM TSTM WND DMG HOLYOKE 42.21N 72.64W
06/06/2020 HAMPDEN MA AMATEUR RADIO
TREE DOWN ON JACKSON AT HIGH ST
0224 PM TSTM WND DMG HOLYOKE 42.21N 72.64W
06/06/2020 HAMPDEN MA AMATEUR RADIO
TREE DOWN ON JACKSON AT MAPLE ST
0225 PM TSTM WND DMG WEST BROOKFIELD 42.24N 72.15W
06/06/2020 WORCESTER MA AMATEUR RADIO
TREE DOWN ON BIRCH HILL RD
0240 PM TSTM WND DMG STURBRIDGE 42.10N 72.06W
06/06/2020 WORCESTER MA AMATEUR RADIO
TREE AND WIRES DOWN
0244 PM TSTM WND DMG SPENCER 42.24N 71.99W
06/06/2020 WORCESTER MA AMATEUR RADIO
TREE DOWN ON NORTHWEST RD
0302 PM TSTM WND DMG OXFORD 42.12N 71.87W
06/06/2020 WORCESTER MA AMATEUR RADIO
WIRES DOWN ON SUTTON AVE
0302 PM TSTM WND DMG AUBURN 42.20N 71.83W
06/06/2020 WORCESTER MA AMATEUR RADIO
WIRES DOWN ON SOUTH ST
0306 PM TSTM WND DMG NORTHBRIDGE 42.15N 71.65W
06/06/2020 WORCESTER MA AMATEUR RADIO
TREE DOWN ON PURGATORY RD
&&
EVENT NUMBER BOX2001482 BOX2001483 BOX2001484 BOX2001485 BOX2001486
BOX2001487 BOX2001488 BOX2001489 BOX2001490 BOX2001491
RCPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
337 PM EDT SAT JUN 06 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0310 PM TSTM WND DMG NORTHBRIDGE 42.15N 71.65W
06/06/2020 WORCESTER MA TRAINED SPOTTER
TREE AND LARGE BRANCHES DOWN
0330 PM TSTM WND DMG UXBRIDGE 42.08N 71.60W
06/06/2020 WORCESTER MA TRAINED SPOTTER
TREES DOWN ON BAILEY ST
&&
EVENT NUMBER BOX2001492
EVENT NUMBER BOX2001493
RCThe Boston radar (KBOX), 22 km away, was scanning. The volume nearest the first event began at 19:39 UTC.
1 thunderstorm wind. Local standard time, as filed.
In Cumberland, a tree was down on a house...street not documented.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Rhode Island in 2020Every state in 2020This day in weather historyWarnings in Rhode Island, June 2020
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 894096.