Alert archive / Connecticut / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 7, NWS Boston/Norton, MA

May 15, 2018Capitol Planning Region, Connecticut; Hampden County, Massachusetts

NWS Boston/Norton, MA issued this severe thunderstorm warning at May 15, 2018, 3:46 PM EDT for Capitol Planning Region, Connecticut; Hampden County, Massachusetts. It was in force for 59 min. 18 reports came from inside the area while it was in force.

The area

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

The facts

Issued: May 15, 2018, 3:46 PM EDT (19:46 UTC)
Expired: May 15, 2018, 4:45 PM EDT
In force: 59 min
Issued by: NWS Boston/Norton, MA
Area: Storm-based polygon
Tornado: Possible
Hail: 1.5 in
Wind: 60.0 mph

Counties Capitol Planning Region, CT, Hampden County, MA

The radar

The Brookhaven radar (KOKX), 115 km from the middle of the area, began a volume at 19:46 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

Time	Report	Where	Remark
May 15, 4:00 PM EDT	HAIL 1	East Hartland, CT
May 15, 4:00 PM EDT	HAIL 1.75	Hartland, CT
May 15, 4:05 PM EDT	HAIL 0.88	Granville, MA	TRAINED SPOTTER
May 15, 4:06 PM EDT	HAIL 2	East Hartland, CT
May 15, 4:10 PM EDT	HAIL 0.88	Granville, MA
May 15, 4:10 PM EDT	HAIL 1.5	Southwick, MA	TRAINED SPOTTER
May 15, 4:11 PM EDT	HAIL 1	Granby, CT	HAIL COVERING GROUND
May 15, 4:11 PM EDT	HAIL 1.25	Granby, CT
May 15, 4:11 PM EDT	HAIL 1.75	Granby, CT	MULTIPLE CARS ON ROUTE 20 WITH WINDSHIELDS DAMAGED
May 15, 4:11 PM EDT	HAIL 1.75	Granby, CT	MULTIPLE CARS ON RTE 20 WITH WINDSHIELS DAMAGED
May 15, 4:15 PM EDT	HAIL 2.5	Granby, CT	CAR WINDSHIELDS AND HOUSE WINDOWS SMASHED BY TENNIS BALL SIZE HAIL
May 15, 4:18 PM EDT	HAIL 1	Southwick, MA
May 15, 4:40 PM EDT	TSTM WND DMG	Somers, CT	TREES AND WIRES DOWN ON SPRINGFIELD ROAD AT TURNPIKE ROAD AND GRIST MILL TERRACE
May 15, 4:40 PM EDT	TSTM WND DMG	Somers, CT	TRESS AND WIRES DOWN ON TURNPIKE ROAD
May 15, 4:45 PM EDT	TSTM WND DMG	Bloomfield, CT	TREES DOWN ON DUNCASTER AND HOPKINS ROAD
May 15, 4:45 PM EDT	TSTM WND DMG	Bloomfield, CT	TREES DOWN ON DUNCASTER ROAD AND HOSKINS ROAD
May 15, 4:45 PM EDT	TSTM WND DMG	Simsbury, CT	TREES DOWN ON OLD FARMS ROAD NEAR TOLLGATE LANE, HOLCOMB ROAD AT CARDINAL ROAD, BARNDOOR HILLS ROAD AND FIRETOWN ROAD, AND TREE DOWN ACROSS RICHARD ROAD
May 15, 4:45 PM EDT	TSTM WND DMG	Union, CT	TREE AND WIRES DOWN ON BUCKLEY HIGHWAY

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

The watch it was issued in

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

Issued	Product	Office	Lasted
May 15, 2:23 PM EDT	Tornado Watch	SPC	4 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 7.8 hours before the alert went out and 115 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 909 m above ground
0-6 km bulk shear: 36 kt
0-1 km storm-relative helicity: 107 m²/s²
0-3 km storm-relative helicity: 153 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

277 
WUUS51 KBOX 151946
SVRBOX
CTC003-013-MAC013-152045-
/O.NEW.KBOX.SV.W.0007.180515T1946Z-180515T2045Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Boston/Norton MA
346 PM EDT TUE MAY 15 2018

The National Weather Service in Boston/Norton has issued a

* Severe Thunderstorm Warning for...
  Tolland County in northern Connecticut...
  Hartford County in northern Connecticut...
  Hampden County in western Massachusetts...

* Until 445 PM EDT.

* At 345 PM EDT, a severe thunderstorm was located near Hartland, or
  14 miles northeast of Torrington, moving east at 40 mph.

  HAZARD...Up to ping pong ball size hail and 60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...People and animals outdoors will be injured. Expect hail 
           damage to roofs, siding, windows, and vehicles. Expect 
           damage to trees and power lines.

* Locations impacted include...
  Springfield, Hartford, New Britain, West Hartford, Meriden,
  Bristol, Manchester, Chicopee, East Hartford, Enfield, Southington,
  Westfield, Holyoke, Glastonbury, Newington, Vernon, Windsor,
  Agawam, West Springfield and Wethersfield.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Prepare immediately for large hail and damaging winds. People outside
should move immediately to shelter inside a strong building. Stay
away from windows.

&&

A Tornado Watch remains in effect until 900 PM EDT for northern
Connecticut...and western and central Massachusetts.

LAT...LON 4220 7226 4215 7220 4216 7214 4196 7210
      4196 7222 4175 7216 4172 7225 4160 7234
      4158 7246 4165 7251 4163 7271 4155 7285
      4156 7294 4180 7302 4181 7295 4197 7289
      4197 7303 4204 7301 4204 7306 4215 7307
TIME...MOT...LOC 1945Z 272DEG 35KT 4202 7301 

TORNADO...POSSIBLE
HAIL...1.50IN
WIND...60MPH
 
$$

Sipprell

1 follow-up statement

684 
WWUS51 KBOX 152023
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
423 PM EDT TUE MAY 15 2018

MAC013-152032-
/O.CAN.KBOX.SV.W.0007.000000T0000Z-180515T2045Z/
Hampden MA-
423 PM EDT TUE MAY 15 2018

...THE SEVERE THUNDERSTORM WARNING FOR HAMPDEN COUNTY IS CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A Tornado Watch remains in effect until 900 PM EDT for northern
Connecticut...and western and central Massachusetts.

LAT...LON 4203 7301 4203 7281 4200 7281 4203 7275
      4203 7211 4196 7210 4196 7222 4175 7216
      4172 7225 4160 7234 4158 7246 4165 7251
      4163 7271 4155 7285 4156 7294 4180 7302
      4181 7295 4197 7289 4197 7303
TIME...MOT...LOC 2022Z 272DEG 35KT 4201 7252 

$$

CTC003-013-152045-
/O.CON.KBOX.SV.W.0007.000000T0000Z-180515T2045Z/
Tolland CT-Hartford CT-
423 PM EDT TUE MAY 15 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 445 PM EDT
FOR TOLLAND AND HARTFORD COUNTIES...

At 422 PM EDT, a severe thunderstorm was located over Enfield, moving
east at 40 mph.

HAZARD...Two inch hail and 60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...People and animals outdoors will be injured. Expect hail 
         damage to roofs, windows, siding, and vehicles. Expect 
         damage to trees and power lines.

Locations impacted include...
Hartford, New Britain, West Hartford, Meriden, Bristol, Manchester,
East Hartford, Enfield, Southington, Glastonbury, Newington, Vernon,
Windsor, Wethersfield, Mansfield, South Windsor, Farmington, Windham,
Wolcott and Colchester.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Prepare immediately for large hail and damaging winds. People outside
should move to a shelter, inside a strong building and away from
windows.

&&

A Tornado Watch remains in effect until 900 PM EDT for northern
Connecticut...and western and central Massachusetts.

LAT...LON 4203 7301 4203 7281 4200 7281 4203 7275
      4203 7211 4196 7210 4196 7222 4175 7216
      4172 7225 4160 7234 4158 7246 4165 7251
      4163 7271 4155 7285 4156 7294 4180 7302
      4181 7295 4197 7289 4197 7303
TIME...MOT...LOC 2022Z 272DEG 35KT 4201 7252 

TORNADO...POSSIBLE
HAIL...2.00IN
WIND...60MPH
 
$$
Field

The office that day

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

Issued	Product	Office	Counties	Lasted
May 15, 3:06 PM EDT	Severe Thunderstorm Warning	BOX	Capitol Planning Region	54 min
May 15, 3:36 PM EDT	Tornado Warning	BOX	Capitol Planning Region	24 min
May 15, 4:02 PM EDT	Tornado Warning	BOX	Capitol Planning Region	28 min
May 15, 4:42 PM EDT	Severe Thunderstorm Warning	BOX	Capitol Planning Region, Northeastern Connecticut Planning Region	63 min
May 15, 5:31 PM EDT	Special Weather Statement	BOX		59 min
May 15, 5:48 PM EDT	Severe Thunderstorm Warning	BOX	Northeastern Connecticut Planning Region	27 min
May 15, 11:08 AM EDT	Special Weather Statement	BOX	Franklin, Hampshire	37 min
May 15, 3:13 PM EDT	Severe Thunderstorm Warning	BOX	Franklin, Hampshire	47 min
May 15, 3:33 PM EDT	Severe Thunderstorm Warning	BOX	Franklin, Hampshire, Worcester	42 min
May 15, 4:31 PM EDT	Special Weather Statement	BOX	Middlesex	44 min
May 15, 4:59 PM EDT	Severe Thunderstorm Warning	BOX	Middlesex, Suffolk, Worcester	31 min
May 15, 5:03 PM EDT	Special Marine Warning	BOX		57 min
May 15, 5:27 PM EDT	Special Weather Statement	BOX	Norfolk	48 min
May 15, 5:37 PM EDT	Special Marine Warning	BOX		83 min
May 15, 6:14 PM EDT	Special Weather Statement	BOX	Bristol, Dukes, Plymouth	61 min
May 15, 6:21 PM EDT	Special Marine Warning	BOX		70 min
May 15, 6:56 PM EDT	Special Marine Warning	BOX		34 min

Nearby

Severe Thunderstorm Warnings in Connecticut, 2018 Severe Thunderstorm Warnings in Massachusetts, 2018 Every 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.