Massachusetts, 2020

Flash Flooding and Flooding in Massachusetts, August 23, 2020

August 23, 2020 · NWS BOX · 57 events in 9 counties and zones

Diurnally driven thunderstorms brought wind damage, hail, and some flooding to mainly western and central Massachusetts.

Where it happened

Every event with a place to put it. Tap one for its entry below.

  • Tornadoes
  • Tropical storms and surge
  • Floods
  • Wind
  • Hail
  • Winter weather
  • Heat and drought
  • Cold
  • Fire, smoke and dust
  • Marine and coastal
  • Other

Open the live radar over this ground

The toll

Deaths
0
Injuries
0
Property damage
$149,000
Crop damage
None recorded
Events
57

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.

What happened

The episode as NWS BOX wrote it up.

Diurnally driven thunderstorms brought wind damage, hail, and some flooding to mainly western and central Massachusetts.

What forecasters said that day

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 Aug 23, 1:07 PM EST, 49 minutes earlier.

Area forecast discussion, Aug 23, 1:07 PM EST, 49 minutes before
Area Forecast Discussion
National Weather Service Boston/Norton MA
207 PM EDT Sun Aug 23 2020

.SYNOPSIS...
Warm and humid conditions continue this afternoon into early
next week. Scattered strong thunderstorms are expected this
afternoon and evening and a few Monday afternoon and evening.
But will have better chances of more widespread thunderstorm
activity on Tuesday as a cold front slides through. Strong to
severe storms are possible on Tuesday. Cooler, dry and fall-
like feel expected Wednesday. Unsettled weather returns late in
the week heading into weekend with temperatures and humidity
trending upward.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
2 PM update...

Scattered strong thunderstorms have already formed in northern
MA. Expected threat for strong and isolated severe thunderstorms
to continue into this evening and expand southward to perhaps
northern CT and northern RI. Downdraft CAPE is very high...near
1000 J/kg, so damaging winds are possible with the storms. Mid
level lapse rates are not terribly shabby...near 6 C/km which
will keep storms going. Will need to watch for possible
development on sea breeze boundary as well, especially in
northeast MA.

Otherwise, it was very warm and humid. Temperatures already hit
93 degrees at BAF and 92 at BDL in the CT River Valley.
Dewpoints were in the mid 60s to near 70.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
Tonight:

Any leftover storms should be weakening and/or moving offshore early
tonight. Should see improving conditions as we move into the
midnight/early-overnight hrs. However higher moisture levels in
sustained albeit light SW flow should bring low clouds and fog to
the South Coast and the Cape. This could extend further into the
interior as well, especially in/around areas which receive rain
today. Muggy evening again with lows in the mid 60s to near 70.

Monday:

Broadly cyclonic zonal flow aloft with weak sea-level pressure
pattern again the rule for Monday. Early-day low clouds/mist to burn
off by mid-Monday morning, but Monday should feature a bit more in
the way of cloudiness. Nonetheless still quite warm and humid
conditions to again prevail, which will again foster moderately
strong convective instability values. However lifting mechanisms are
subtle to absent and lack of better convergence may lead to less
shower/storm coverage on Monday than today. Only showed 30-40% PoPs
for showers and storms. Highs in the mid 80s to near 90 in the
interior and in the lower 80s near the coasts.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
Highlights

* Warm and muggy Tuesday with chances of showers and
  thunderstorms. Strong to severe storms possible as a cold
  front slides through.

* Dry and quiet on Wednesday and will feel like autumn, but this
  appears to be short lived as temperatures and humidity levels rise
  late in the week into next weekend.

* Weather appears to be more unsettled late in the week heading into
  the weekend - but details are hazy at this point in time.

Monday night into Tuesday...

Mid level shortwave trough flattens out as it moves through southern
New England Monday Night into early Tuesday. The main focus of this
period is the potent trough located over northern Ontario/James Bay
Monday night which will dig southeastward into the eastern Great
Lakes and northern New England. At the surface a cold front will
slide across the eastern Great Lakes and through southern New
England.

Any shower/storm activity from Monday will be winding down during
the evening as the shortwave slides offshore and as instability
wanes due to the loss of heating.

Main thing that will need to be determined in future updates is the
exact timing/speed the cold front passes through the region. Have
leaned on the ECMWF/GFS/CMC, which are in good agreement and feature
a slower moving cold front versus a very fast NAM. The convective
parameter space does indicate a risk of strong to severe
thunderstorms especially with the slower model solutions. Will see
dew points in the middle to upper 60s ahead of the front.
Instability values will range from roughly 1000-2000 J/kg of MLCAPE
with deep layer shear increasing to 35 to 50 kts. On top of this it
appears that an EML will be moving in from the Upper Midwest. Should
see mid level lapse rates of roughly 6-7 degrees Celsius per km,
which should help sustain updrafts of any thunderstorms that can get
going. Low level lapse rates are around roughly 7-8.5 degrees
Celsius per km and K index values of 25-35. On top of the severe
threat there could be locally heavy downpours as PWATS are around
roughly 1.5 to 1.75 inches. Think the flooding threat should limited
given how dry we have been and storms should be moving along. Could
have a risk of strong gust and hail with thunderstorms as well. The
matches up well with SPCs latest Day 3 Outlook, which has the region
under a Slight Risk.

Increased high temperatures toward the 75th percentile of guidance
as am anticipating W to WNW flow. This will promote downsloping, but
have held off for now from the 90th as the cold front timing and
cloud cover is in question. This results in high temperatures in the
mid to upper 80s across most areas. Could see some lower 90 degrees
readings in the CT River Valley, Merrimack Valley into northern RI.
Will feel muggy with the dew points in the middle to upper 60s.

Tuesday night through Wednesday...

The upper trough slides offshore Tuesday night into early Wednesday,
while a ridge builds from Manitoba into Ontario. At the surface a
Canadian high will nudge into the region from Ontario.

Should have any leftover showers/storms come to an end Tuesday
evening and skies clear. Will feel like autumn with a much cooler
air mass advecting in. Will see sub 10 degree Celsius 850 hPa air
advect into the region with northwesterly flow aloft. Should remain
a bit breezy Tuesday night as the pressure gradient remains tight
over southern New England due to the departing cold front and high
nudging in. Low temperatures cool into the 50s across the region,
with dew points plummeting into the upper 40s and mid 50s.

Fair weather expected on Wednesday across southern New England.
Still may be a bit breezy at times, but will be comfortable with dew
points in the 40s to low 50s. High temperatures will be in the 70s
across the region.

Wednesday night through Saturday...

The ridge over Ontario flattens Wednesday night into early Thursday.
Shortwave trough or the remnants of a thunderstorm complex work its
way southeastward into southern New England on Thursday. Remain
under quasi-zonal flow into early Friday. Uncertain on what will
occur late in the week into the weekend as models begin to interact
with the remnants of Laura. Given the uncertainty in this timeframe
have stuck with the NBM guidance. Still does not appear to be any
washouts until potentially Friday/Saturday.

Do anticipate rising temperatures and humidity levels as flow aloft
shifts from the NW to a W and eventually a SW direction. Looks at
this time that readings will rise into the lower to middle 80s by
Saturday.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
Forecaster Confidence Levels...

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

19Z update...

This afternoon...High confidence.

VFR except brief IFR in scattered thunderstorms through 02Z.
Greatest coverage mainly along/N of a KBDL-KPYM line. More
isolated/conditional TSRA threat southward from PVD to Cape Cod.
A few TSRA may become severe with wind gusts to 50 kt and hail.

Winds mainly SW 10-15 kt, locally stronger at the Cape airports
where stronger low-level jet could support occasional 20 kt
gusts. Sea breezes and onshore flow along the coast.

Tonight...High confidence.

Any thunderstorms diminish this evening. Will likely have brief
VFR conditions, but expected MVFR to LIFR fog and stratus
tonight especially along the south coast. Any areas where a
shower/storm moves through this afternoon will have a better
opportunity for fog developing. Light SW winds.

Monday: High confidence.

Early-day IFR-LIFR fog and/or stratus burning off soon after
sunrise. Mainly VFR though strong heating will again lead to a
risk for SHRA/TSRA, but coverage may be less than today. SW-WSW
winds 4-8 kt with sea- breezes at BOS.

KBOS Terminal...High confidence in TAF. Sea-breeze around
14-15z, potential time window for VCTS/TSRA ~20-01z.

KBDL Terminal...High confidence in TAF. Potential time window for
VCTS/TSRA ~18-22z.

Outlook /Monday Night through Thursday/...

Monday Night: VFR. Slight chance SHRA, isolated TSRA.

Tuesday: VFR. Breezy. Chance SHRA, chance TSRA.

Tuesday Night through Wednesday: VFR. Breezy.

Wednesday Night: Mainly VFR, with local MVFR possible.

Thursday: Mainly VFR, with areas MVFR possible. Chance SHRA.

&&

.MARINE...
2 PM update...

Most waters should remain below SCA levels and will carry no marine
headlines thru Monday. Could have some stronger SW gusts later today
across the waters in/around Cape Cod, in the low-20s kt range.
Appears too marginal for SCA however. Lighter SWlys anticipated on
Monday (gusts AOB 15 kt). Seas mainly 3 ft or less thru Monday.

Daily chances for afternoon and evening thunderstorms developing
on land then moving over the waters. Will also see vsbys lower
again tonight with fog developing. Vsbys could be as low as
one-quarter mile along the southern waters tonight.

Outlook /Monday Night through Thursday/...

Monday Night: Winds less than 25 kt. Seas locally approaching
5 ft. Slight chance of rain showers, isolated thunderstorms,
patchy fog.

Tuesday: Winds less than 25 kt. Seas locally approaching 5 ft.
Chance of rain showers, chance of thunderstorms.

Tuesday Night: Winds less than 25 kt. Seas up to 5 ft.

Wednesday: Winds less than 25 kt. Areas of seas approaching
5 ft.

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

Thursday: Winds less than 25 kt. Seas locally approaching 5 ft.
Chance of rain showers.

&&

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

&&

SYNOPSIS...BL/Loconto/Field
NEAR TERM...Field
SHORT TERM...Loconto
LONG TERM...BL
AVIATION...BL/Loconto/Field
MARINE...BL/Loconto/Field
Hazardous weather outlook, Aug 23, 9:40 AM EST, 4 hours 16 minutes before
Hazardous Weather Outlook
National Weather Service Boston/Norton MA
1040 AM EDT Sun Aug 23 2020

CTZ002>004-MAZ002>016-026-RIZ001-002-008-240915-
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 Middlesex MA-
Northwest Providence RI-Southeast Providence RI-Block Island RI-
1040 AM EDT Sun Aug 23 2020

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

.DAY ONE...Today and tonight.

Scattered strong to isolated severe thunderstorms are expected late
this afternoon into early tonight. Locally damaging winds are the
main hazard, although small hail also is possible.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

Strong to severe thunderstorms are possible on Tuesday ahead of a
strong cold front.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

ANZ230>237-250-251-254>256-240915-
Boston Harbor-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-Massachusetts Bay and Ipswich Bay-
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-
504 AM EDT Sun Aug 23 2020

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

.DAY ONE...Today and tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

MAZ017>024-RIZ003>007-240915-
Northern Bristol MA-Western Plymouth MA-Eastern Plymouth MA-
Southern Bristol MA-Southern Plymouth MA-Barnstable MA-Dukes MA-
Nantucket MA-Western Kent RI-Eastern Kent RI-Bristol RI-
Washington RI-Newport RI-
504 AM EDT Sun Aug 23 2020

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

.DAY ONE...Today and tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

Strong to severe thunderstorms are possible on Tuesday ahead of a
strong cold front.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

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, Aug 23, 11:07 AM EST, 2 hours 49 minutes before
Special Weather Statement
National Weather Service Boston/Norton MA
1207 PM EDT Sun Aug 23 2020

CTZ002>004-MAZ002>019-026-RIZ001>004-232000-
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-Northern Middlesex MA-
Northwest Providence RI-Southeast Providence RI-Western Kent RI-
Eastern Kent RI-
Including the cities of Hartford, Windsor Locks, Union, Vernon,
Putnam, Willimantic, Charlemont, Greenfield, Orange, Barre,
Fitchburg, Framingham, Lowell, Lawrence, Gloucester,
Chesterfield, Blandford, Amherst, Northampton, Springfield,
Milford, Worcester, Foxborough, Norwood, Cambridge, Boston,
Quincy, Taunton, Brockton, Plymouth, Ayer, Foster, Smithfield,
Providence, Coventry, West Greenwich, East Greenwich, Warwick,
and West Warwick
1207 PM EDT Sun Aug 23 2020

...SCATTERED STRONG TO ISOLATED SEVERE THUNDERSTORMS POSSIBLE
AFTER 2 OR 3 PM THIS AFTERNOON WITH THE GREATEST RISK IN NORTHERN
MASSACHUSETTS...

Scattered thunderstorms are expected to develop after 2 or 3 pm
this afternoon and continue into early this evening. While the
activity will hit or miss, a few of the storms may become severe.
The main concern is localized straight line wind damage, but an
isolated report of hail or two is also possible. In addition,
heavy rain may result in brief localized urban street flooding.

While the risk for isolated severe weather exists across the
entire region, the greatest potential exists in northern and
northeast Massachusetts.

Lastly, dangerous cloud to ground lightning is possible as well.
Those with outdoor plans should keep an eye to the sky and be
prepared to seek an indoor shelter if threatening weather
approaches.

Frank
Special weather statement, Aug 23, 12:50 PM EST, 1 hour 6 minutes before
Special Weather Statement
National Weather Service Boston/Norton MA
150 PM EDT Sun Aug 23 2020

MAZ003-231815-
Eastern Franklin MA-
150 PM EDT Sun Aug 23 2020

...STRONG THUNDERSTORM IN FRANKLIN COUNTY...

At 149 PM EDT, Doppler radar was tracking a strong thunderstorm over
Montague, or near Greenfield, moving east at 20 mph.

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

Locations impacted include...
Greenfield, Orange, Deerfield, Montague, Northfield, Erving, Gill,
New Salem, Wendell and Warwick.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4253 7258 4261 7259 4265 7230 4252 7230
TIME...MOT...LOC 1749Z 266DEG 16KT 4258 7248

Frank
Special weather statement, Aug 23, 1:17 PM EST, 39 minutes before
Special Weather Statement
National Weather Service Boston/Norton MA
217 PM EDT Sun Aug 23 2020

MAZ003-004-231900-
Eastern Franklin MA-Northern Worcester MA-
217 PM EDT Sun Aug 23 2020

...STRONG THUNDERSTORM IN EASTERN FRANKLIN COUNTY...

At 217 PM EDT, Doppler radar was tracking a strong thunderstorm over
Wendell, or near Orange, moving east at 15 mph.

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

Locations impacted include...
Orange, Athol, Winchendon, Montague, Templeton, Barre, Hubbardston,
Northfield, Erving, Phillipston, Gill, Royalston, Petersham, New
Salem, Wendell and Warwick.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4252 7248 4262 7249 4268 7210 4245 7206
TIME...MOT...LOC 1817Z 266DEG 15KT 4257 7239

Frank
Special weather statement, Aug 23, 1:36 PM EST, 20 minutes before
Special Weather Statement
National Weather Service Boston/Norton MA
236 PM EDT Sun Aug 23 2020

MAZ005>007-231915-
Eastern Essex MA-Central Middlesex County MA-Western Essex MA-
236 PM EDT Sun Aug 23 2020

...STRONG THUNDERSTORM PRODUCING TORRENTIAL RAINFALL APPROACHING
ESSEX AND MIDDLESEX COUNTY IN MASSACHUSETTS...

At 234 PM EDT, Doppler radar was tracking a strong thunderstorm over
Salem, moving east at 10 mph.

Penny size hail and wind gusts up to 50 mph will accompany this
storm. This storm has a history of producing 50 mph winds and 4
inches per hour rainfall rate in Southern New Hampshire.

Locations impacted include...
Lawrence, Haverhill, Methuen, Dracut, North Andover, Newburyport,
Amesbury, Ipswich, Salisbury, Georgetown, Boxford, Newbury,
Groveland, Merrimac, Topsfield, Rowley and West Newbury.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Get indoors when this storm approaches. Winds may be strong enough
to produce minor damage, such as a few downed branches. Do not drive
through flooded roadways.

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.

&&

LAT...LON 4265 7090 4271 7128 4274 7124 4274 7118
      4279 7118 4282 7115 4282 7113 4281 7107
      4286 7103 4287 7097 4289 7093 4289 7090
TIME...MOT...LOC 1834Z 272DEG 11KT 4280 7121

Chai

The radar

The Boston radar (KBOX), 123 km away, was scanning. The volume nearest the first event began at 18:55 UTC.

Open the radar archive at this moment

Event by event

37 thunderstorm wind, 9 flood, 7 hail, 2 flash flood, 2 lightning. Local standard time, as filed.

Thunderstorm Wind, Franklin

When
August 23, 1:56 PM EST to 2:15 PM EST
Where
Franklin County, 0.18 mi SSE of Wendell Depot to 1.55 mi SSW of Tully
Measured
50 kt (58 mph) estimated gust
Property damage
$3,000
Reported by
Law Enforcement
Coordinates
42.598, -72.348

In Orange, there were trees down on North Orange Rd, West Orange Rd, Wheeler Ave, and North Main Street.

Thunderstorm Wind, Franklin

When
August 23, 2:26 PM EST to 2:36 PM EST
Where
Franklin County, 0.93 mi NE of Orange Arpt to 0.73 mi NNE of Orange Arpt
Measured
50 kt (58 mph) estimated gust
Property damage
$5,000
Reported by
Amateur Radio
Coordinates
42.579, -72.266

In Orange, there were trees and wires down on East River St, Main St, Hillcrest Rd, Daniel Shays Hwy, Rogers Ave, and Brookside Rd.

Thunderstorm Wind, Worcester

When
August 23, 2:31 PM EST to 2:40 PM EST
Where
Worcester County, 2.57 mi WSW of Athol to 2.81 mi WSW of Athol
Measured
50 kt (58 mph) estimated gust
Property damage
$7,000
Reported by
Amateur Radio
Coordinates
42.580, -72.262

In Athol, a tree was down on a house on Roosevelt Ave. Also, a large tree was down on Orchard Hill Rd, and a tree was down on wires on Orchard Hill Rd.

Thunderstorm Wind, Worcester

When
August 23, 2:43 PM EST to 2:45 PM EST
Where
Worcester County, 0.67 mi ENE of Fitchburg to 2.81 mi N of Fitchburg
Measured
50 kt (58 mph) estimated gust
Property damage
$6,000
Reported by
Amateur Radio
Coordinates
42.583, -71.787

In Fitchburg, a tree was down on a house at Brigham Park. Trees and poles were down on Ashby State Rd.

Thunderstorm Wind, Worcester

When
August 23, 2:45 PM EST
Where
Worcester County, 1.69 mi NE of Lunenburg
Measured
50 kt (58 mph) estimated gust
Property damage
$6,000
Reported by
Amateur Radio
Coordinates
42.619, -71.698

In Lunenburg, a tree was down on cars on Cove Rd.

Thunderstorm Wind, Middlesex

When
August 23, 2:46 PM EST
Where
Middlesex County, 1.54 mi SW of Vose to 0.79 mi SSW of Shirley Center
Measured
50 kt (58 mph) estimated gust
Property damage
$4,000
Reported by
Amateur Radio
Coordinates
42.605, -71.653

In Shirley, multiple trees were down on wires on Center Rd. Large trees were down on Townsend Rd.

Thunderstorm Wind, Worcester

When
August 23, 2:46 PM EST
Where
Worcester County, 0.3 mi NNE of Whalom
Measured
50 kt (58 mph) estimated gust
Property damage
$500
Reported by
Amateur Radio
Coordinates
42.524, -71.747

In Leominster, a tree was down blocking 7th St.

Thunderstorm Wind, Middlesex

When
August 23, 2:52 PM EST
Where
Middlesex County, 1.85 mi NNW of Ayer to 1.6 mi NNW of Ayer
Measured
50 kt (58 mph) estimated gust
Property damage
$3,000
Reported by
Amateur Radio
Coordinates
42.575, -71.591

In Ayer, trees and wires were down on Jonathan Dr. and Groton School Rd.

Thunderstorm Wind, Middlesex

When
August 23, 3:10 PM EST
Where
Middlesex County, 2.08 mi E of East Acton
Measured
50 kt (58 mph) estimated gust
Property damage
$500
Reported by
Amateur Radio
Coordinates
42.478, -71.389

In Concord, a tree was down on College Rd.

Thunderstorm Wind, Essex

When
August 23, 3:12 PM EST
Where
Essex County, 1.17 mi ESE of Middleton
Measured
50 kt (58 mph) estimated gust
Property damage
$4,000
Reported by
Amateur Radio
Coordinates
42.595, -70.998

In Middleton, a tree was down on a house on Oak Rd.

Thunderstorm Wind, Essex

When
August 23, 3:20 PM EST
Where
Essex County, 1.48 mi ESE of East Boxford to 1.19 mi N of Topsfield
Measured
50 kt (58 mph) estimated gust
Property damage
$2,000
Reported by
Amateur Radio
Coordinates
42.659, -70.955

In Topsfield, a tree and wires were down on Haverhill Rd (Rt 97) at Ipswich Rd. A tree was down on Rowley Rd and a tree was down on wires on Wilmor Rd.

Thunderstorm Wind, Essex

When
August 23, 3:24 PM EST
Where
Essex County, 0.86 mi NW of North Andover Center
Measured
50 kt (58 mph) estimated gust
Property damage
$4,000
Reported by
Amateur Radio
Coordinates
42.690, -71.130

In North Andover, a tree was down on a car on Woodstock Rd.

Hail, Middlesex

When
August 23, 3:45 PM EST
Where
Middlesex County, Wakefield
Measured
1 in hail
Reported by
Amateur Radio
Coordinates
42.500, -71.070

In Wakefield quarter sized hail was reported.

Thunderstorm Wind, Middlesex

When
August 23, 3:45 PM EST to 3:50 PM EST
Where
Middlesex County, 0.76 mi SSE of Melrose to 0.58 mi S of Wakefield
Measured
50 kt (58 mph) estimated gust
Property damage
$12,000
Reported by
Amateur Radio
Coordinates
42.461, -71.062

In Wakefield, trees were down on Avon St and Green St. A tree was down on a house on Main St. near the lake. Myrtle Ave was blocked by 5 large trees downed. A tree was down on Commuter Rail train tracks.

Thunderstorm Wind, Middlesex

When
August 23, 3:45 PM EST
Where
Middlesex County, 0.82 mi ESE of Farm Hill
Measured
50 kt (58 mph) estimated gust
Property damage
$4,000
Reported by
Amateur Radio
Coordinates
42.474, -71.086

In Stoneham, a tree was down on a car on Franklin St.

Hail, Essex

When
August 23, 3:55 PM EST
Where
Essex County, 0.51 mi W of Lynn
Measured
0.75 in hail
Reported by
Amateur Radio
Coordinates
42.470, -70.960

In Lynn, dime sized hail was reported.

Thunderstorm Wind, Worcester

When
August 23, 3:56 PM EST
Where
Worcester County, 0.72 mi W of Barre Plains to 1.35 mi NNW of Barre Plains
Measured
55 kt (63 mph) estimated gust
Property damage
$4,000
Reported by
Amateur Radio
Coordinates
42.381, -72.114

In Barre, a large tree was down on Loring Rd in the area of South St. A tree was down on Root Rd at South St. A tree and wires were down on Clen Ct. A tree and wires were down on Church St and Adams St. A tree was down across the tracks at the South Barry Railway Station.

Hail, Suffolk

When
August 23, 4:00 PM EST
Where
Suffolk County, 0.47 mi NE of Fairmount
Measured
0.75 in hail
Reported by
Amateur Radio
Coordinates
42.255, -71.123

In the Hyde Park section of Boston, dime sized hail was reported.

Hail, Worcester

When
August 23, 4:05 PM EST
Where
Worcester County, Auburn
Measured
0.75 in hail
Reported by
Trained Spotter
Coordinates
42.200, -71.830

In Auburn, dime sized hail was reported.

Thunderstorm Wind, Essex

When
August 23, 4:05 PM EST
Where
Essex County, 1 mi SSE of North Saugus
Measured
50 kt (58 mph) estimated gust
Property damage
$800
Reported by
Amateur Radio
Coordinates
42.487, -71.010

In Saugus, a tree was down on wires on Hobson St.

Thunderstorm Wind, Worcester

When
August 23, 4:05 PM EST
Where
Worcester County, 2.15 mi SE of Oakham
Measured
50 kt (58 mph) estimated gust
Property damage
$800
Reported by
Amateur Radio
Coordinates
42.325, -72.025

In Oakham, a tree and wires were down on Spencer Rd.

Thunderstorm Wind, Middlesex

When
August 23, 4:06 PM EST
Where
Middlesex County, 0.7 mi N of Broadway
Measured
50 kt (58 mph) estimated gust
Property damage
$500
Reported by
Trained Spotter
Coordinates
42.440, -71.032

In Malden, a tree was down on Rt. 99 just west of Rt 1.

Thunderstorm Wind, Worcester

When
August 23, 4:15 PM EST
Where
Worcester County, 1.36 mi SSW of Rutland Hgts
Measured
50 kt (58 mph) estimated gust
Property damage
$500
Reported by
Amateur Radio
Coordinates
42.351, -71.986

In Rutland, a tree and wires were down on Barre Paxton Rd.

Thunderstorm Wind, Worcester

When
August 23, 4:18 PM EST
Where
Worcester County, 0.51 mi E of (Orh)worcester Muni
Measured
54 kt (62 mph) measured gust
Reported by
ASOS
Coordinates
42.270, -71.870

In Worcester, the ASOS at Worcester Airport recorded a gust to 62 mph.

Thunderstorm Wind, Worcester

When
August 23, 4:20 PM EST
Where
Worcester County, 0.54 mi E of Westborough Arpt
Measured
50 kt (58 mph) estimated gust
Property damage
$500
Reported by
Amateur Radio
Coordinates
42.269, -71.639

In Westborough, a tree was down on Fisher St at Otis St.

Thunderstorm Wind, Worcester

When
August 23, 4:25 PM EST to 4:30 PM EST
Where
Worcester County, 0.98 mi WNW of Dorothy Manor to 1.31 mi ESE of South Worcester
Measured
50 kt (58 mph) estimated gust
Property damage
$8,000
Reported by
Amateur Radio
Coordinates
42.223, -71.769

In Worcester, a tree went through a trailer on Southwest Cutoff (Rt 20). Also, a tree was down on Brightwood Ave.

Flood, Worcester

When
August 23, 4:25 PM EST
Where
Worcester County, 0.65 mi WSW of Westwood Hills to 0.55 mi WSW of Westwood Hills
Cause
Heavy Rain
Reported by
Amateur Radio
Coordinates
42.278, -71.842

In Worcester, there was 3-4 ft of street flooding on Pleasant St, possibly from clogged drainage.

Flood, Worcester

When
August 23, 4:30 PM EST
Where
Worcester County, 1.69 mi NE of Westborough to 1.68 mi NE of Westborough
Cause
Heavy Rain
Reported by
Amateur Radio
Coordinates
42.286, -71.596

In Westborough, flooding was reported at Rt 9 and East Main St.

Thunderstorm Wind, Worcester

When
August 23, 4:35 PM EST
Where
Worcester County, 2.04 mi NE of Westborough to 1.03 mi SSW of Westborough Arpt
Measured
50 kt (58 mph) estimated gust
Property damage
$2,000
Reported by
Amateur Radio
Coordinates
42.294, -71.596

In Westborough, trees were down on wires on Carolyn Dr, Linda St, and Haskell St.

Thunderstorm Wind, Worcester

When
August 23, 4:40 PM EST
Where
Worcester County, 0.55 mi NNW of Westwood Hills to 0.25 mi NNW of Lincoln Square
Measured
50 kt (58 mph) estimated gust
Property damage
$4,000
Reported by
Amateur Radio
Coordinates
42.287, -71.836

In Worcester, a telephone pole was snapped due to a tree falling on wires on Aylesbury St. A tree was down on Edgeworth St.

Hail, Worcester

When
August 23, 4:41 PM EST
Where
Worcester County, 0.51 mi W of Worcester
Measured
1 in hail
Reported by
Amateur Radio
Coordinates
42.270, -71.810

In Worcester, quarter sized hail was reported.

Flood, Worcester

When
August 23, 4:41 PM EST
Where
Worcester County, 0.64 mi SSE of Worcester to 0.66 mi SSE of Worcester
Cause
Heavy Rain
Reported by
Amateur Radio
Coordinates
42.261, -71.795

In Worcester, Washington Square was flooded to an unknown depth.

Flash Flood, Worcester

When
August 23, 4:44 PM EST to 4:45 PM EST
Where
Worcester County, 0.25 mi N of Worcester to 1.01 mi SW of South Worcester
Cause
Heavy Rain
Property damage
$5,000
Reported by
Amateur Radio
Coordinates
42.274, -71.800

In Worcester, a car was stuck in flooding on the Rt 146 offramp to I-290. The Franklin St Train Bridge was impassable due to flash flooding.

Thunderstorm Wind, Norfolk

When
August 23, 4:46 PM EST
Where
Norfolk County, (Owd)norwood Mem Arp
Measured
51 kt (59 mph) measured gust
Reported by
ASOS
Coordinates
42.180, -71.170

In Norwood, the ASOS at Norwood Airport recorded a wind gust to 59 mph.

Thunderstorm Wind, Norfolk

When
August 23, 4:46 PM EST
Where
Norfolk County, 2.14 mi NNE of Ponkapog
Measured
52 kt (60 mph) measured gust
Reported by
COOP Observer
Coordinates
42.210, -71.110

In Miilton, a wind gust to 60 mph was measured atop Blue Hill.

Flood, Worcester

When
August 23, 4:47 PM EST
Where
Worcester County, 1.58 mi ESE of (Orh)worcester Muni to 1.6 mi ESE of (Orh)worcester Muni
Cause
Heavy Rain
Property damage
$3,000
Reported by
Amateur Radio
Coordinates
42.260, -71.852

In Worcester, catch basins overflowed resulting in flooding into a residence on Outlook Dr.

Flash Flood, Worcester

When
August 23, 4:51 PM EST to 4:59 PM EST
Where
Worcester County, 0.64 mi NNE of Jamesville to 1.17 mi NW of Dorothy Manor
Cause
Heavy Rain
Property damage
$25,000
Reported by
Amateur Radio
Coordinates
42.238, -71.844

In Worcester, a vehicle drove into flood waters and got stuck on Dewey St which was impassable. On Webster St a person was trapped when his car filled with water. Also, Grafton St was closed from Dana St to Warner Ave.

Thunderstorm Wind, Norfolk

When
August 23, 5:00 PM EST
Where
Norfolk County, 0.83 mi SSW of Canton Jct to 0.55 mi NW of Canton
Measured
50 kt (58 mph) estimated gust
Property damage
$3,000
Reported by
Amateur Radio
Coordinates
42.159, -71.158

In Canton, trees and wires were down on Lawrence St and Fuller St.

Thunderstorm Wind, Norfolk

When
August 23, 5:00 PM EST
Where
Norfolk County, 1.21 mi S of Endicott to 1.3 mi S of Endicott
Measured
50 kt (58 mph) estimated gust
Property damage
$3,000
Reported by
Amateur Radio
Coordinates
42.212, -71.172

In Westwood, a large tree and wires were down on Hawktree Drive and Magaletta Dr. Multiple trees and wires were down on Strasser Ave and Fearing Drive.

Thunderstorm Wind, Worcester

When
August 23, 5:00 PM EST
Where
Worcester County, 0.1 mi SW of Dorothy Manor
Measured
50 kt (58 mph) estimated gust
Property damage
$500
Reported by
Amateur Radio
Coordinates
42.219, -71.751

In Millbury, a tree was down on Cristo Ln.

Thunderstorm Wind, Worcester

When
August 23, 5:00 PM EST
Where
Worcester County, 0.68 mi NNW of Greenville to 1.35 mi WNW of (Orh)worcester Muni
Measured
50 kt (58 mph) estimated gust
Property damage
$3,000
Reported by
Amateur Radio
Coordinates
42.209, -71.926

In Leicester, a tree was down on wires on Henshaw St at South Main St. A tree was down on powerlines on White Birch St. A tree was down on Marshall St. A tree was down on Greenville Cr.

Thunderstorm Wind, Middlesex

When
August 23, 5:10 PM EST
Where
Middlesex County, 0.61 mi SSE of Braggville to 0.35 mi SW of Holliston
Measured
50 kt (58 mph) estimated gust
Property damage
$2,000
Reported by
Amateur Radio
Coordinates
42.162, -71.475

In Holliston, a high voltage power line was down on Pearl St. A tree and wires were down on Holly Ln. A tree was down on South St. at Fisher St.

Flood, Norfolk

When
August 23, 5:10 PM EST
Where
Norfolk County, 1.66 mi NNE of (Owd)norwood Mem Arp to 1.86 mi NNE of (Owd)norwood Mem Arp
Cause
Heavy Rain
Reported by
Amateur Radio
Coordinates
42.201, -71.154

In Westwood, Yale St at Univertsity Ave was flooded and impassable.

Thunderstorm Wind, Bristol

When
August 23, 5:30 PM EST
Where
Bristol County, 0.5 mi W of Furnace Vlg to 0.63 mi S of South Easton
Measured
50 kt (58 mph) estimated gust
Property damage
$1,000
Reported by
Amateur Radio
Coordinates
42.021, -71.140

In Easton, a tree was down on Highland St and a tree was down on wires on Depot St.

Flood, Norfolk

When
August 23, 5:30 PM EST
Where
Norfolk County, 0.4 mi WNW of Canton to 0.33 mi WNW of Canton
Cause
Heavy Rain
Property damage
$2,000
Reported by
Amateur Radio
Coordinates
42.152, -71.137

In Canton, a car was stuck in flooding on Boliver St.

Hail, Worcester

When
August 23, 5:53 PM EST
Where
Worcester County, New Braintree
Measured
0.75 in hail
Reported by
Amateur Radio
Coordinates
42.320, -72.130

In New Braintree, dime sized hail was reported.

Flood, Worcester

When
August 23, 5:53 PM EST
Where
Worcester County, 2.39 mi NNW of West Brookfield to 2.47 mi NNW of West Brookfield
Cause
Heavy Rain
Reported by
Amateur Radio
Coordinates
42.264, -72.161

In West Brookfield, Shea Rd was closed from Birch Hill Rd to Wickaboag Rd due to flooding.

Thunderstorm Wind, Worcester

When
August 23, 5:55 PM EST
Where
Worcester County, 0.4 mi E of Warren to 0.94 mi WSW of West Brookfield
Measured
50 kt (58 mph) estimated gust
Property damage
$2,000
Reported by
Amateur Radio
Coordinates
42.220, -72.192

In West Brookfield, trees and wires were down on Miller Dr. A tree was down on Rt 67 near the West Brookfield line.

Flood, Worcester

When
August 23, 5:57 PM EST
Where
Worcester County, 1.34 mi NW of West Brookfield to 1.33 mi NW of West Brookfield
Cause
Heavy Rain
Reported by
Amateur Radio
Coordinates
42.243, -72.170

In West Brookfield, Snow Rd at Rt 9 was closed due to flooding.

Thunderstorm Wind, Hampshire

When
August 23, 6:04 PM EST to 6:10 PM EST
Where
Hampshire County, 0.37 mi S of Cold Spg to 1.51 mi ENE of Belchertown
Measured
50 kt (58 mph) estimated gust
Property damage
$5,000
Reported by
Amateur Radio
Coordinates
42.245, -72.350

In Belchertown, power lines were down on Aldrich Dr. A large tree was down on power lines on Warner St. Multiple trees and wires were down on East St from Swift River Wildlife to Cold Spring Rd.

Lightning, Worcester

When
August 23, 6:05 PM EST
Where
Worcester County, New Braintree
Property damage
$500
Reported by
Amateur Radio
Coordinates
42.320, -72.130

In New Braintree, a house was struck by lightning with some smoke in the building.

Thunderstorm Wind, Worcester

When
August 23, 6:05 PM EST
Where
Worcester County, 2.38 mi NNW of West Brookfield to 0.69 mi NNW of Brookfield Arpt
Measured
50 kt (58 mph) estimated gust
Property damage
$10,000
Reported by
Amateur Radio
Coordinates
42.261, -72.169

In West Brookfield, a tree was down on a house and car on New Braintree Rd. A tree fell onto a roof of a house on East Main St. A tree was down on wires on Myrick Rd. Multiple trees and wires were down on Ragged Hill Rd.

Hail, Hampshire

When
August 23, 6:10 PM EST
Where
Hampshire County, 0.69 mi S of Belchertown
Measured
0.75 in hail
Reported by
Amateur Radio
Coordinates
42.270, -72.400

In Belchertown, dime sized hail was reported.

Thunderstorm Wind, Hampshire

When
August 23, 6:30 PM EST
Where
Hampshire County, 1.48 mi SE of West Ware to 1.43 mi W of Ware Center
Measured
50 kt (58 mph) estimated gust
Property damage
$2,000
Reported by
Amateur Radio
Coordinates
42.256, -72.308

In Ware, trees and wires were down on Belchertown Rd and a tree was down on Beaver Rd.

Thunderstorm Wind, Hampden

When
August 23, 6:39 PM EST
Where
Hampden County, 0.91 mi NW of Whipples
Measured
50 kt (58 mph) estimated gust
Property damage
$500
Reported by
Amateur Radio
Coordinates
42.209, -72.333

In Palmer, a tree was down on State Rd.

Lightning, Hampden

When
August 23, 7:32 PM EST
Where
Hampden County, 0.86 mi SW of East Springfield
Property damage
$2,000
Reported by
Amateur Radio
Coordinates
42.120, -72.540

In Springfield, lightning struck a house causing a fire on White St.

Flood, Hampden

When
August 23, 7:45 PM EST
Where
Hampden County, 0.67 mi SSE of Armory
Cause
Heavy Rain
Property damage
$1,000
Reported by
Amateur Radio
Coordinates
42.111, -72.566

In Springfield, a car was stuck in flooding on State St.

What these are

Thunderstorm Wind
Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.
Hail
Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
Flood
Flooding that develops more slowly than a flash flood: rivers leaving their banks, or water standing over land for an extended time.
Flash Flood
Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.
Lightning
A lightning strike that killed, injured or caused damage.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in Massachusetts in 2020Every state in 2020This day in weather historyWarnings in Massachusetts, August 2020

Sources

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: 916266, 916267, 916270, 916272, 916273, 916274, 916275, 916276, 916277, 916278, 916279, 916280, 916257, 916281, 916282, 916258, 916284, 916259, 916260, 916285, 916286, 916287, 916288, 916319, 916289, 916290, 916325, 916326, 916292, 916295, 916261, 916327, 916323, 916320, 916321, 916328, 916324, 916298, 916300, 916301, and more.