Alert archive / Massachusetts / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 34, NWS Boston/Norton, MA

July 17, 2018Bristol County, Norfolk County, Plymouth County, Massachusetts

NWS Boston/Norton, MA issued this severe thunderstorm warning at Jul 17, 2018, 5:47 PM EDT for Bristol County, Norfolk County, Plymouth County, Massachusetts. It was in force for 43 min. 1 report 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
Jul 17, 2018, 5:47 PM EDT (21:47 UTC)
Expired
Jul 17, 2018, 6:30 PM EDT
In force
43 min
Issued by
NWS Boston/Norton, MA
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Bristol County, MA, Norfolk County, MA, Plymouth County, MA

The radar

The Boston radar (KBOX), 28 km from the middle of the area, began a volume at 21:52 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
Jul 17, 6:10 PM EDTTSTM WND DMGBrockton, MATREES AND WIRES DOWN ON WINTER STREET

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 one storm report to this severe thunderstorm warning; the first came 23 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
Jul 17, 11:17 AM EDTSevere Thunderstorm WatchSPC8 hr

The nearest sounding before it

Chatham, MA (KCHH), launched 12:00Z, 9.8 hours before the alert went out and 81 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Chatham, MA at 12:00Z on 2018-07-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 159 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, Chatham, MA at 12:00Z on 2018-07-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -13 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
159 J/kg
Mixed-layer CIN
-122 J/kg
Mixed-layer LCL
702 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
-13 m²/s²
0-3 km storm-relative helicity
3 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

129 
WUUS51 KBOX 172147
SVRBOX
MAC005-021-023-172230-
/O.NEW.KBOX.SV.W.0034.180717T2147Z-180717T2230Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Boston/Norton MA
547 PM EDT TUE JUL 17 2018

The National Weather Service in Boston/Norton has issued a

* Severe Thunderstorm Warning for...
  Southeastern Norfolk County in eastern Massachusetts...
  Northern Plymouth County in southeastern Massachusetts...
  North central Bristol County in southeastern Massachusetts...

* Until 630 PM EDT.

* At 546 PM EDT, a severe thunderstorm was located over Easton, or
  near Brockton, moving east at 30 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Brockton, Plymouth, Taunton, Weymouth, Braintree, Randolph,
  Norwood, Stoughton, Bridgewater, Marshfield, Walpole, Mansfield,
  Middleborough, Easton, Hingham, Canton, Norton, Scituate, Pembroke
  and Sharon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4198 7062 4197 7067 4193 7120 4216 7126
      4223 7073 4200 7059
TIME...MOT...LOC 2146Z 254DEG 28KT 4203 7111 

HAIL...<.75IN
WIND...60MPH
 
$$

md
2 follow-up statements
833 
WWUS51 KBOX 172214
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
614 PM EDT TUE JUL 17 2018

MAC005-021-023-172230-
/O.CON.KBOX.SV.W.0034.000000T0000Z-180717T2230Z/
Norfolk MA-Plymouth MA-Bristol MA-
614 PM EDT TUE JUL 17 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 630 PM EDT
FOR EAST CENTRAL NORFOLK...CENTRAL PLYMOUTH AND NORTH CENTRAL BRISTOL
COUNTIES...

At 614 PM EDT, a severe thunderstorm was located over Pembroke, or
near Marshfield, moving east at 30 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Brockton, Plymouth, Taunton, Weymouth, Braintree, Randolph,
Bridgewater, Marshfield, Middleborough, Easton, Hingham, Norton,
Scituate, Pembroke, Rockland, Abington, Duxbury, Whitman, Hanover and
East Bridgewater.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4198 7062 4197 7066 4193 7114 4217 7103
      4223 7073 4200 7059
TIME...MOT...LOC 2214Z 254DEG 28KT 4209 7082 

HAIL...<.75IN
WIND...60MPH
 
$$

md
016 
WWUS51 KBOX 172226
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
626 PM EDT TUE JUL 17 2018

MAC005-021-023-172235-
/O.EXP.KBOX.SV.W.0034.000000T0000Z-180717T2230Z/
Norfolk MA-Plymouth MA-Bristol MA-
626 PM EDT TUE JUL 17 2018

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL NORFOLK...CENTRAL
PLYMOUTH AND NORTH CENTRAL BRISTOL COUNTIES WILL EXPIRE AT 630 PM
EDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.

A Severe Thunderstorm Watch remains in effect until 700 PM EDT for
eastern and southeastern Massachusetts.

LAT...LON 4198 7062 4197 7066 4193 7114 4217 7103
      4223 7073 4200 7059
TIME...MOT...LOC 2225Z 254DEG 28KT 4211 7071 

$$

md

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 Jul 17, 5:31 PM EDT, 16 minutes earlier.

Area forecast discussion, Jul 17, 5:31 PM EDT, 16 minutes before
Area Forecast Discussion
National Weather Service Boston/Norton MA
531 PM EDT Tue Jul 17 2018

.SYNOPSIS...
Widespread showers and thunderstorms with locally damaging wind
gusts and isolated flash flooding continue into this
evening...before gradually diminishing in areal coverage and
intensity. Other than perhaps some lingering showers early
Wednesday across Cape Cod and Nantucket, dry weather is
anticipated the rest of the work week along with much lower
humidity including warm afternoons and cool nights. Unsettled
weather may return sometime Sunday into Monday along with
increasing humidity.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...

* Urban Flash Flood/Isolated Severe Weather Threat Now Confined
  to Areas Along And Southeast of BOS-PVD Corridor

The atmosphere has been worked over enough that the concern for
additional urban flash flooding and isolated severe weather
should be confined to areas along and southeast of the Boston to
Providence corridor. Southeast of the region MLCape values
remained around 1500 J/KG but were lower along the south coast
with the marine influence. Localized urban flooding remains the
concern for the next 1 to 3 hours in this region...but isolated
severe thunderstorms with localized damaging wind gusts also
remain possible. The severe/flash flood watch headlines have
been adjusted based on these conditions. Will probably see the
activity weaken as it continues to push southeast as instability
diminishes a bit and this area is also further removed from the
forcing.

The steady showers were already coming to an end across western
MA and northern CT. Meanwhile...the isolated severe weather
threat will diminish in the next 1 to 3 hours across eastern
MA/RI...enough elevated instability will remain for showers and
embedded thunderstorms with locally heavy rain to continue into
the evening. In fact...areas along and especially southeast of
the Boston to Providence corridor may see showers and embedded
thunderstorms persist after midnight.

Low temperatures by daybreak will be in the 60s to near 70. Will
also have to watch for some low clouds and fog across the
Cape/Islands.

&&

.SHORT TERM /6 AM WEDNESDAY THROUGH 6 AM WEDNESDAY/...
Wednesday...

A much better day of weather on tap for Wednesday behind the
cold front. Perhaps a few lingering showers across the
Cape/Islands into mid to late morning. Otherwise...becoming
mostly sunny with high temperatures into the 80s in most
locations although a bit cooler across portions of the
Cape/Islands. Much lower humidity though will make for a much
more comfortable day across the entire region.

&&

.LONG TERM /WEDNESDAY THROUGH TUESDAY/...
Highlights...

* Dry and much less humid later Wed thru Fri, possibly into Sat
* Highs 80-85 each afternoon and 50s at night
* Showers/storms and humid conditions return Sunday/Monday

Overview...

17.00z ensembles (ECENS & GEFS) show northeast trough Wednesday
departing and deamplifying which gives way to ridging Friday and
likely lingering into Saturday. At the surface this translates to a
cold front slowly exiting the Cape Wed followed by 1018 mb high
pressure building into New England Wed night/Thu and accompanied by
a much less humid airmass. The high then moves offshore Friday but
with ridge axis arcing back into New England thru Saturday.
Ensembles suggest northern stream remains active with robust mid
level trough entering the Great Lakes this weekend and taking on a
negative tilt along the eastern seaboard Sun/Mon. This will support
a return to more humid weather along with risk of showers/T-storms.

Temperatures...

850 mb temps begin Wed around +13C/+14C but then lower to about +11C
in the post frontal airmass Thu morning, but modify to +13C by days
end, yielding highs in the low 80s away from coastal seabreezes.
Airmass slow warms to about +15C Friday and Saturday which will
support highs in the mid 80s inland. However humidity remains
comfortable as seen by GEFS PWATs remaining below normal (1 to
2 standard deviations below normal) thru Sat with core of dry
air over the region Wed night into Thu. This dry airmass will
support lows in the 50s overnight, very comfortable. Also given
high pres overhead Thu ngt decided to lean toward the cooler MOS
guidance per ideal radiational cooling conditions. This dry
column will also yield plenty of sunshine Thu and Fri, possibly
Sat as well. 850 mb temps remain about +15C Sunday but do warm
to about +17C Mon. However the main story Sun/Mon will be the
increasing humidity as the low level flow becomes southerly and
advects dew pts into the 60s Sunday and then low to mid 70s
Monday!

Precipitation...

Any organized showers/T-storms will be focused across Cape Cod and
Nantucket Wed morning as slow moving cold front and frontal wave
move across this region in the morning. Trailing short wave sweeps
across the region later in the day along with attending cold front
moving offshore. Thus drying trend Wed which persist Thu, Fri and
likely into Sat. Next chance of showers/T-storms likely arrives Sun
and Mon as negative tilt mid level trough dives out of the Great
Lakes into the Mid Atlc region. Heavy rainers possible as
subtropical stream gets captured by negative tilt trough sending
PWATs of +1 to +2 standard deviations up the eastern seaboard into
New England Sun/Mon.

&&

.AVIATION /22Z TUESDAY THROUGH SUNDAY/...
Forecaster Confidence Levels...

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

Short Term /through Tonight/...

Into Mid evening...Moderate confidence. Numerous showers and
thunderstorms with localized torrential rainfall will continue
to gradually press southeast across the region. Main focus will
be eastern MA and RI although some weakening should occur as
activity nears the south coast. A few of the storms may
continue to produce localized strong wind gusts. So while VFR
conditions may dominate outside the storms...IFR to even brief
LIFR conditions will be possible under the core of the storms.

Later This Evening Through Tonight...Moderate to high
confidence. Activity should weaken some as it gets southeast of
the Boston to Providence corridor this evening...but some
showers and embedded t-storms with brief heavy rain are still
possible. Conditions improve to VFR across most locations later
this evening. However...southwest flow will result in low
clouds and fog across the Cape/Islands.

Wednesday...High confidence. Lingering low clouds/fog patches
across the Cape/Islands during the morning lift by late
morning/early afternoon.  Otherwise...VFR conditions.

KBOS Terminal...Moderate confidence in TAF. Thunderstorms to
impact the terminal through 20 or 21z.

KBDL Terminal...Moderate confidence in TAF. Thunderstorms to
impact the terminal through 20 or 21z.

Outlook /Wednesday through Sunday/...

Wednesday through Thursday: VFR.

Thursday Night: Mainly VFR, with local IFR possible.

Friday: VFR.

Friday Night: Mainly VFR, with local IFR possible. Patchy BR.

Saturday: VFR.

&&

.MARINE...
Forecaster Confidence Levels...

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

Short Term /through Tonight/...

Tonight...High confidence. Near shore southwest wind gusts of 25
knots should diminish this evening along with the marginal 5
foot seas across the outer-waters. Therefore...small craft
headlines will be allowed to expire by midnight. However...main
concern is a few strong storms across our near shore waters this
evening with gusty winds.

Wednesday...High confidence. Winds and seas should remain below
small craft thresholds. Some northeast wind gusts around 20
knots or so are possible across the Cape/Islands.

Outlook /Wednesday through Sunday/...

Wednesday: Winds less than 25 kt. Areas of seas approaching
5 ft. Slight chance of rain showers, patchy fog.

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

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

Thursday Night through Friday Night: Winds less than 25 kt.

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

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Flash Flood Watch until 10 PM EDT this evening for CTZ004.
MA...Flash Flood Watch until 10 PM EDT this evening for MAZ005>007-
     012>017.
RI...Flash Flood Watch until 10 PM EDT this evening for RIZ001>004.
MARINE...Small Craft Advisory until 6 PM EDT this evening for
     ANZ230>234-236-251.
     Small Craft Advisory until 8 PM EDT this evening for ANZ235-
     237.
     Small Craft Advisory until 11 PM EDT this evening for ANZ250-
     254>256.

&&

SYNOPSIS...Frank/Nocera
NEAR TERM...Frank
SHORT TERM...Frank
LONG TERM...Nocera
AVIATION...Frank/Nocera
MARINE...Frank/Nocera
Hazardous weather outlook, Jul 17, 5:05 PM EDT, 42 minutes before
Hazardous Weather Outlook
National Weather Service Boston/Norton MA
505 PM EDT Tue Jul 17 2018

CTZ002-003-MAZ002>004-008>011-022>024-026-RIZ005>008-182115-
Hartford CT-Tolland CT-Western Franklin MA-Eastern Franklin MA-
Northern Worcester MA-Western Hampshire MA-Western Hampden MA-
Eastern Hampshire MA-Eastern Hampden MA-Barnstable MA-Dukes MA-
Nantucket MA-Northern Middlesex MA-Bristol RI-Washington RI-
Newport RI-Block Island RI-
505 PM EDT Tue Jul 17 2018

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

.DAY ONE...Tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be needed.

CTZ004-MAZ005>007-012-014-182115-
Windham CT-Central Middlesex MA-Western Essex MA-Eastern Essex MA-
Southern Worcester MA-Southeast Middlesex MA-
505 PM EDT Tue Jul 17 2018

...FLASH FLOOD WATCH IN EFFECT UNTIL 10 PM EDT THIS EVENING...

This Hazardous Weather Outlook is for northern Connecticut, central
Massachusetts, eastern Massachusetts and northeastern Massachusetts.

.DAY ONE...Tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Flash Flood Watch.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be needed.

MAZ013-015>017-RIZ001>004-182115-
Western Norfolk MA-Suffolk MA-Eastern Norfolk MA-Northern Bristol MA-
Northwest Providence RI-Southeast Providence RI-Western Kent RI-
Eastern Kent RI-
505 PM EDT Tue Jul 17 2018

...SEVERE THUNDERSTORM WATCH 278 IN EFFECT UNTIL 7 PM EDT THIS
EVENING...
...FLASH FLOOD WATCH IN EFFECT UNTIL 10 PM EDT THIS EVENING...

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

.DAY ONE...Tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Severe Thunderstorm Watch.
   Flash Flood Watch.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be needed.

MAZ018>021-182115-
Western Plymouth MA-Eastern Plymouth MA-Southern Bristol MA-
Southern Plymouth MA-
505 PM EDT Tue Jul 17 2018

...SEVERE THUNDERSTORM WATCH 278 IN EFFECT UNTIL 7 PM EDT THIS
EVENING...

This Hazardous Weather Outlook is for southeastern Massachusetts.

.DAY ONE...Tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Severe Thunderstorm Watch.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be needed.

ANZ231>237-250-254>256-182115-
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-
505 PM EDT Tue Jul 17 2018

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

.DAY ONE...Tonight.

A few strong thunderstorms are possible over the waters late this
afternoon and early evening.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be needed.

ANZ230-251-182115-
Boston Harbor-Massachusetts Bay and Ipswich Bay-
505 PM EDT Tue Jul 17 2018

...SEVERE THUNDERSTORM WATCH 278 IN EFFECT UNTIL 7 PM EDT THIS
EVENING...

This Hazardous Weather Outlook is for Massachusetts coastal waters.

.DAY ONE...Tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Severe Thunderstorm Watch.

A few strong thunderstorms are possible over the waters late this
afternoon and early evening.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be needed.

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

You can follow us on Facebook at
www.facebook.com/NWSBoston

You can follow us on Twitter at
@NWSBoston

In the hours before

Special weather statement, Jul 17, 3:43 PM EDT, 2 hours 4 minutes before
Special Weather Statement
National Weather Service Boston/Norton MA
343 PM EDT TUE JUL 17 2018

MAZ004-005-012-026-172030-
Northwest Middlesex County MA-Southern Worcester MA-
Central Middlesex County MA-Northern Worcester MA-
343 PM EDT TUE JUL 17 2018

...STRONG THUNDERSTORM...

At 343 PM EDT, Doppler radar was tracking a strong thunderstorm over
Millbury, or near Worcester, moving northeast at 25 mph.

Winds in excess of 40 mph will accompany this storm.

Locations impacted include...
Worcester, Framingham, Marlborough, Shrewsbury, Natick, Hudson,
Westborough, Grafton, Sudbury, Ashland, Auburn, Northbridge,
Hopkinton, Northborough, Oxford, Clinton, Millbury, Wayland, Maynard
and Southborough.

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 4207 7174 4219 7188 4257 7163 4234 7133
TIME...MOT...LOC 1943Z 208DEG 22KT 4221 7176

md
Local storm report, Jul 17, 4:06 PM EDT, 1 hour 41 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
406 PM EDT TUE JUL 17 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0308 PM     FLOOD            WINTHROP                42.38N  70.98W
07/17/2018                   SUFFOLK            MA   AMATEUR RADIO

            WASHINGTON AVE AT DELBYS CORNER FLOODED OUT

0309 PM     FLASH FLOOD      CHICOPEE                42.18N  72.57W
07/17/2018                   HAMPDEN            MA   AMATEUR RADIO

            MEETING HOUSE ROAD FLOODED OUT AND IMPASSABLE

0310 PM     FLASH FLOOD      WESTFIELD               42.14N  72.76W
07/17/2018                   HAMPDEN            MA   AMATEUR RADIO

            CAR STUCK IN FLOOD WATERS AT RTE 20 AND MOUNTAIN ROAD
            INTERSEXTION. ROAD IS CLOSED

&&

EVENT NUMBER BOX1804151
EVENT NUMBER BOX1804152
EVENT NUMBER BOX1804153

WS
Special weather statement, Jul 17, 4:32 PM EDT, 1 hour 15 minutes before
Special Weather Statement
National Weather Service Boston/Norton MA
432 PM EDT TUE JUL 17 2018

MAZ005-012-013-172130-
Southern Worcester MA-Western Norfolk MA-Central Middlesex County MA-
432 PM EDT TUE JUL 17 2018

...STRONG THUNDERSTORM...

At 432 PM EDT, Doppler radar was tracking a strong thunderstorm over
Sutton, or 10 miles south of Worcester, moving northeast at 30 mph.

Winds in excess of 40 mph will accompany this storm.

Locations impacted include...
Worcester, Framingham, Marlborough, Shrewsbury, Natick, Franklin,
Milford, Walpole, Acton, Hudson, Westborough, Grafton, Concord,
Sudbury, Webster, Ashland, Bellingham, Auburn, Northbridge and
Hopkinton.

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 roads or underpasses. Avoid low lying
areas near small streams.

&&

LAT...LON 4205 7184 4214 7192 4246 7143 4216 7125
TIME...MOT...LOC 2032Z 236DEG 25KT 4212 7177

md
Special weather statement, Jul 17, 5:08 PM EDT, 39 minutes before
Special Weather Statement
National Weather Service Boston/Norton MA
508 PM EDT TUE JUL 17 2018

MAZ005-007-013>016-019-172200-
Eastern Essex MA-Eastern Plymouth MA-Suffolk MA-Western Norfolk MA-
Central Middlesex County MA-Eastern Norfolk MA-
Southeast Middlesex MA-
508 PM EDT TUE JUL 17 2018

...STRONG THUNDERSTORM...

At 508 PM EDT, Doppler radar was tracking a strong thunderstorm over
Wellesley, moving northeast at 30 mph.

Winds in excess of 40 mph will accompany this storm along with
torrential rainfall.

Locations impacted include...
Boston, Cambridge, Quincy, Lynn, Newton, Somerville, Framingham,
Waltham, Malden, Brookline, Medford, Weymouth, Revere, Peabody,
Arlington, Everett, Salem, Braintree, Chelsea and Natick.

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 roads or underpasses. Avoid low lying
areas near small streams.

&&

LAT...LON 4246 7087 4244 7091 4241 7090 4242 7095
      4235 7093 4235 7086 4232 7087 4227 7079
      4222 7077 4215 7133 4238 7142 4252 7090
TIME...MOT...LOC 2108Z 246DEG 28KT 4228 7129

md
Local storm report, Jul 17, 5:17 PM EDT, 30 minutes before
PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
517 PM EDT TUE JUL 17 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0144 PM     FLASH FLOOD      LOWELL                  42.64N  71.32W
07/17/2018                   MIDDLESEX          MA   PUBLIC

            FLOODING ON ROUTE 38 AT PARKVIEW STREET

0148 PM     FLASH FLOOD      WESTFIELD               42.14N  72.76W
07/17/2018                   HAMPDEN            MA   BROADCAST MEDIA

            STREET FLOODING ON MEADOW STEET

0217 PM     FLASH FLOOD      CHICOPEE                42.18N  72.57W
07/17/2018                   HAMPDEN            MA   AMATEUR RADIO

            BOTTOM OF SIMARD STREET IS COMPLETELY FLOODED AND
            IMPASSABLE

0219 PM     FLASH FLOOD      BELCHERTOWN             42.27N  72.40W
07/17/2018                   HAMPSHIRE          MA   AMATEUR RADIO

            ROUTE 202 AT GRANBY TOWN LINE FLOODED

0225 PM     FLASH FLOOD      CHICOPEE                42.18N  72.57W
07/17/2018                   HAMPDEN            MA   AMATEUR RADIO

            NOTHEAST MAIN STREET AND ARCADE STREET FLOODED

0228 PM     FLASH FLOOD      SAUGUS                  42.47N  71.02W
07/17/2018                   ESSEX              MA   BROADCAST MEDIA

            STREET FLOODING IN CLIFTONDALE SQUARE

0240 PM     FLASH FLOOD      GLOUCESTER              42.62N  70.65W
07/17/2018                   ESSEX              MA   AMATEUR RADIO

            SECTION OF ESSEX AVE IS FLOODED

0248 PM     FLASH FLOOD      WEST SPRINGFIELD        42.12N  72.65W
07/17/2018                   HAMPDEN            MA   AMATEUR RADIO

            BOTH LANES OF DEWEY STREET ARE FLOODED

0253 PM     FLASH FLOOD      BOSTON                  42.32N  71.07W
07/17/2018                   SUFFOLK            MA   AMATEUR RADIO

            DEVON STREET AT COLUMBIA ROAD IS FLOODED

0257 PM     FLASH FLOOD      WELLESLEY               42.30N  71.29W
07/17/2018                   NORFOLK            MA   AMATEUR RADIO

            EASTBOUND SIDE OF WALNUT STREET IS FLOODED OUT

0300 PM     FLASH FLOOD      WEST SPRINGFIELD        42.12N  72.65W
07/17/2018                   HAMPDEN            MA   AMATEUR RADIO

            CAR STUCK IN FLOOD WATERS ON OLD WESTFIELD ROAD DUE TO
            PONDING WATER UNDER TRAIN TRACKS

0303 PM     FLASH FLOOD      WESTFIELD               42.14N  72.76W
07/17/2018                   HAMPDEN            MA   AMATEUR RADIO

            SECTION OF CROSS STREET FLOODED

0308 PM     FLOOD            WINTHROP                42.38N  70.98W
07/17/2018                   SUFFOLK            MA   AMATEUR RADIO

            WASHINGTON AVE AT DELBYS CORNER FLOODED OUT

0309 PM     FLASH FLOOD      CHICOPEE                42.18N  72.57W
07/17/2018                   HAMPDEN            MA   AMATEUR RADIO

            MEETING HOUSE ROAD FLOODED OUT AND IMPASSABLE

0310 PM     FLASH FLOOD      CHICOPEE                42.18N  72.57W
07/17/2018                   HAMPDEN            MA   AMATEUR RADIO

            MEETING HOUSE ROAD FLOODED AND IMPASSABLE

0310 PM     FLASH FLOOD      WESTFIELD               42.14N  72.76W
07/17/2018                   HAMPDEN            MA   AMATEUR RADIO

            CAR STUCK IN FLOOD WATERS AND ROAD CLOSED ON ROUTE 20
            AT THE INTERSECTION OF EAST MOUNTAIN ROAD

0310 PM     FLASH FLOOD      WESTFIELD               42.14N  72.76W
07/17/2018                   HAMPDEN            MA   AMATEUR RADIO

            CAR STUCK IN FLOOD WATERS AT RTE 20 AND MOUNTAIN ROAD
            INTERSEXTION. ROAD IS CLOSED

0331 PM     FLOOD            SOMERS                  41.98N  72.45W
07/17/2018                   TOLLAND            CT   AMATEUR RADIO

            STREET FLOODING ON RTE 190

0355 PM     FLASH FLOOD      WORCESTER               42.27N  71.81W
07/17/2018                   WORCESTER          MA   AMATEUR RADIO

            STREET FLOODING ON CHANDLER AND MURRY STREETS WITH ONE
            FOOT OF WATER

0355 PM     FLOOD            WORCESTER               42.27N  71.81W
07/17/2018                   WORCESTER          MA   AMATEUR RADIO

            MULTIPLE ROADS FLOODED OUT ACROSS CITY

0355 PM     FLOOD            AUBURN                  42.20N  71.83W
07/17/2018                   WORCESTER          MA   AMATEUR RADIO

            STREET FOODING ON AUBURN STEET

0410 PM     FLASH FLOOD      AUBURN                  42.20N  71.83W
07/17/2018                   WORCESTER          MA   AIRPLANE PILOT

            ROUTE 20 AND SOUTHBRIDGE STREET FLOODED OUT

0417 PM     FLOOD            MARLBOROUGH             42.35N  71.55W
07/17/2018                   MIDDLESEX          MA   AMATEUR RADIO

            STREET FLOODING ON RTE85 NEAR HILL STREET

0421 PM     FLOOD            OXFORD                  42.12N  71.87W
07/17/2018                   WORCESTER          MA   AMATEUR RADIO

            SUTTON AVE FLOODED OUT

0425 PM     FLASH FLOOD      AUBURN                  42.20N  71.83W
07/17/2018                   WORCESTER          MA   AMATEUR RADIO

            1.5 FEET OF WATER ON RTE 20

&&

EVENT NUMBER BOX1804132 BOX1804137 BOX1804140 BOX1804135 BOX1804141
BOX1804136 BOX1804143 BOX1804144 BOX1804145 BOX1804146 BOX1804147
BOX1804148 BOX1804151 BOX1804152 BOX1804149 BOX1804150 BOX1804153
BOX1804154 BOX1804155 BOX1804156 BOX1804157 BOX1804158 BOX1804159
BOX1804160 BOX1804161

ws
Local storm report, Jul 17, 5:42 PM EDT, 5 minutes before
PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
542 PM EDT TUE JUL 17 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1220 PM     TSTM WND DMG     WINCHENDON              42.68N  72.04W
07/17/2018                   WORCESTER          MA   AMATEUR RADIO

            TREE DOWN ON WIRES ON BALDWINVILLE STATE HIGHWAY AT
            ENTRANCE TO LAKE DENNISON

1251 PM     TSTM WND DMG     BARRE                   42.42N  72.11W
07/17/2018                   WORCESTER          MA   AMATEUR RADIO

            LARGE LIMB AND WIRES DOWN ON PLEASANT STREET

1258 PM     TSTM WND DMG     WESTMINSTER             42.55N  71.90W
07/17/2018                   WORCESTER          MA   AMATEUR RADIO

            TREE DOWN BLOCKING ROAD ON SHADY AVE

0103 PM     TSTM WND DMG     AMHERST                 42.38N  72.52W
07/17/2018                   HAMPSHIRE          MA   AMATEUR RADIO

            WIRES DOWN ON PELHAM ROAD

0110 PM     TSTM WND DMG     WESTFORD                42.58N  71.43W
07/17/2018                   MIDDLESEX          MA   AMATEUR RADIO

            TREE DOWN ON SPRING STREET

0115 PM     TSTM WND DMG     BILLERICA               42.55N  71.27W
07/17/2018                   MIDDLESEX          MA   AMATEUR RADIO

            LARGE TREE DOWN ON SALEM ROAD

0120 PM     TSTM WND DMG     LEOMINSTER              42.52N  71.77W
07/17/2018                   WORCESTER          MA   AMATEUR RADIO

            TREE DOWN ON PLEASANT STREET BY SHOWLAN FARMS

0127 PM     TSTM WND DMG     WILMINGTON              42.56N  71.17W
07/17/2018                   MIDDLESEX          MA   AMATEUR RADIO

            WIRES DOWN ON FALCON ROAD

0128 PM     TSTM WND DMG     BILLERICA               42.55N  71.27W
07/17/2018                   MIDDLESEX          MA   AMATEUR RADIO

            LARGE TREE DOWN BETWEEN FRIENDSHIP STREET AND CLINTON
            STREET

0131 PM     TSTM WND DMG     WILMINGTON              42.56N  71.17W
07/17/2018                   MIDDLESEX          MA   AMATEUR RADIO

            TREE DOWN ACROSS ALSTON AVE

0205 PM     TSTM WND DMG     WELLESLEY               42.30N  71.29W
07/17/2018                   NORFOLK            MA   AMATEUR RADIO

            LARGE TREE BRANCH DOWN ON A MOVING CAR ON WALNUT STREET
            AT WASHINGTON STREET

0215 PM     TSTM WND DMG     BOSTON                  42.32N  71.07W
07/17/2018                   SUFFOLK            MA   AMATEUR RADIO

            TREE DOWN ON DORCHESTER AVE

0236 PM     TSTM WND DMG     SOUTH HADLEY            42.27N  72.57W
07/17/2018                   HAMPSHIRE          MA   AMATEUR RADIO

            7 UTILITY POLES DOWN ON ROUTE 47 AT THE HADLEY LINE

0305 PM     TSTM WND DMG     FARMINGTON              41.72N  72.83W
07/17/2018                   HARTFORD           CT   AMATEUR RADIO

            TREE AND WIRES DOWN ON COLTON STREET

0305 PM     TSTM WND DMG     FARMINGTON              41.72N  72.83W
07/17/2018                   HARTFORD           CT   AMATEUR RADIO

            TREE IN ROAD ON RESERVOIR ROAD

0310 PM     TSTM WND DMG     NEW BRITAIN             41.68N  72.79W
07/17/2018                   HARTFORD           CT   AMATEUR RADIO

            TREE DOWN ON WIRES ON SLATER ROAD

0345 PM     TSTM WND DMG     STAFFORD SPRINGS        41.95N  72.31W
07/17/2018                   TOLLAND            CT   AMATEUR RADIO

            TREE DOWN ON WIRES ON DIAMOND LEDGE ROAD

0405 PM     TSTM WND DMG     ASHFORD                 41.87N  72.12W
07/17/2018                   WINDHAM            CT   AMATEUR RADIO

            WIRES DOWN ON ASHFORD STREET

0405 PM     TSTM WND DMG     ASHFORD                 41.87N  72.12W
07/17/2018                   WINDHAM            CT   AMATEUR RADIO

            LARGE TREE DOWN ON POWER LINES ON SUNSET DRIVE

0419 PM     TSTM WND DMG     POMFRET                 41.90N  71.97W
07/17/2018                   WINDHAM            CT   AMATEUR RADIO

            SMALL TREE DOWN WITH DEBRIS ON QUASSET ROAD

0502 PM     TSTM WND DMG     BURRILLVILLE            41.95N  71.72W
07/17/2018                   PROVIDENCE         RI   AMATEUR RADIO

            LARGE TREE LIMB DOWN ON SNAKE HILL ROAD

&&

EVENT NUMBER BOX1804133 BOX1804124 BOX1804125 BOX1804126 BOX1804127
BOX1804128 BOX1804134 BOX1804129 BOX1804130 BOX1804131 BOX1804138
BOX1804139 BOX1804142 BOX1804162 BOX1804163 BOX1804164 BOX1804165
BOX1804166 BOX1804167 BOX1804168 BOX1804169

ws

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 16, 8:50 PM EDTSpecial Weather StatementBOXFranklin40 min
Jul 16, 8:53 PM EDTSpecial Weather StatementBOXFranklin37 min
Jul 16, 9:17 PM EDTAreal Flood AdvisoryBOXFranklin, Worcester77 min
Jul 17, 3:58 AM EDTHeat AdvisoryBOXBristol, Essex, Middlesex, Norfolk, Worcester12 hr
Jul 17, 4:15 AM EDTFlash Flood WatchBOXBristol, Essex, Franklin, Hampden, Hampshire, Middlesex and 3 more15 hr
Jul 17, 10:46 AM EDTSpecial Weather StatementBOXFranklin44 min
Jul 17, 11:04 AM EDTFlash Flood WarningBOXFranklin, Hampshire3 hr
Jul 17, 11:28 AM EDTSpecial Weather StatementBOXFranklin47 min
Jul 17, 11:36 AM EDTSevere Thunderstorm WarningBOXFranklin, Worcester54 min
Jul 17, 11:39 AM EDTSevere Thunderstorm WarningBOXFranklin, Hampshire51 min
Jul 17, 11:46 AM EDTFlash Flood WarningBOXFranklin, Hampden, Hampshire3 hr
Jul 17, 12:23 PM EDTSpecial Weather StatementBOXMiddlesex37 min
Jul 17, 12:30 PM EDTFlash Flood WarningBOXFranklin, Hampden, Hampshire, Middlesex, Worcester2 hr
Jul 17, 12:33 PM EDTSpecial Weather StatementBOXWorcester42 min
Jul 17, 12:45 PM EDTSevere Thunderstorm WarningBOXFranklin, Hampshire, Worcester45 min
Jul 17, 12:57 PM EDTSevere Thunderstorm WarningBOXMiddlesex, Worcester48 min
Jul 17, 1:08 PM EDTFlash Flood WarningBOXEssex, Middlesex, Norfolk, Plymouth, Suffolk, Worcester112 min
Jul 17, 1:15 PM EDTSevere Thunderstorm WarningBOXEssex, Middlesex60 min
Jul 17, 1:18 PM EDTSpecial Marine WarningBOX57 min
Jul 17, 1:33 PM EDTSevere Thunderstorm WarningBOXEssex, Middlesex, Suffolk45 min
Jul 17, 1:41 PM EDTSpecial Marine WarningBOX64 min
Jul 17, 1:59 PM EDTSevere Thunderstorm WarningBOXFranklin, Hampden, Hampshire, Worcester46 min
Jul 17, 2:22 PM EDTAreal Flood WarningBOXFranklin, Hampden, Hampshire, Worcester3 hr
Jul 17, 3:03 PM EDTAreal Flood WarningBOXEssex, Middlesex, Norfolk, Suffolk, Worcester3 hr
Jul 17, 3:10 PM EDTFlash Flood WarningBOXHampden, Hampshire, Worcester2 hr
Jul 17, 3:27 PM EDTFlash Flood WarningBOXWorcester2 hr
Jul 17, 3:27 PM EDTSpecial Weather StatementBOXWorcester48 min
Jul 17, 3:43 PM EDTSpecial Weather StatementBOXMiddlesex47 min
Jul 17, 4:09 PM EDTAreal Flood WarningBOXNorfolk, Worcester2 hr
Jul 17, 4:23 PM EDTSevere Thunderstorm WarningBOXWorcester52 min
Jul 17, 4:32 PM EDTSpecial Weather StatementBOXMiddlesex58 min
Jul 17, 5:06 PM EDTSevere Thunderstorm WarningBOXBristol, Norfolk, Worcester39 min
Jul 17, 5:08 PM EDTSpecial Weather StatementBOXNorfolk, Suffolk52 min
Jul 17, 5:20 PM EDTFlash Flood WarningBOXMiddlesex, Norfolk, Suffolk60 min
Jul 17, 5:51 PM EDTSpecial Marine WarningBOX54 min
Jul 17, 5:58 PM EDTSpecial Marine WarningBOX92 min
Jul 17, 6:35 PM EDTSpecial Marine WarningBOX40 min
Jul 17, 6:41 PM EDTSpecial Marine WarningBOX64 min
Jul 17, 6:58 PM EDTSpecial Marine WarningBOX27 min
Jul 17, 7:12 PM EDTSpecial Marine WarningBOX48 min
Jul 17, 7:23 PM EDTSpecial Marine WarningBOX67 min
Jul 17, 7:41 PM EDTSpecial Marine WarningBOX49 min

Nearby

Severe Thunderstorm Warnings in Massachusetts, 2018Every severe thunderstorm warning in 2018

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.