Alert archive / Connecticut / Tornado Warnings in 2018

Tornado Warning 2, NWS Boston/Norton, MA

May 15, 2018Capitol Planning Region, Connecticut

NWS Boston/Norton, MA issued this tornado warning at May 15, 2018, 4:02 PM EDT for Capitol Planning Region, Connecticut. It was in force for 28 min. 6 reports came from inside the area while it was in force.

The area

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

The facts

Issued: May 15, 2018, 4:02 PM EDT (20:02 UTC)
Expired: May 15, 2018, 4:30 PM EDT
In force: 28 min
Issued by: NWS Boston/Norton, MA
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 2.0 in

County Capitol Planning Region, CT

The radar

The Brookhaven radar (KOKX), 116 km from the middle of the area, began a volume at 20:02 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, 4:06 PM EDT	HAIL 2	East Hartland, CT
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

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, 8.0 hours before the alert went out and 116 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.

431 
WFUS51 KBOX 152002
TORBOX
CTC003-152030-
/O.NEW.KBOX.TO.W.0002.180515T2002Z-180515T2030Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Boston/Norton MA
402 PM EDT TUE MAY 15 2018

The National Weather Service in Boston/Norton has issued a

* Tornado Warning for...
  Central Hartford County in northern Connecticut...

* Until 430 PM EDT.
    
* At 401 PM EDT, a severe thunderstorm capable of producing a tornado
  was located near Simsbury, or 9 miles northwest of Windsor, moving
  east at 35 mph.

  HAZARD...Tornado and hail up to two inches in diameter.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* This dangerous storm will be near...
  Avon around 410 PM EDT.
  West Hartford and East Granby around 415 PM EDT.
  Hartford, Windsor, Bloomfield and Windsor Locks around 420 PM EDT.
  East Windsor around 425 PM EDT.
  Manchester, Vernon and South Windsor around 430 PM EDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors or in
a vehicle, move to the closest substantial shelter and protect
yourself from flying debris.

&&

LAT...LON 4197 7250 4195 7249 4194 7251 4186 7252
      4186 7250 4181 7251 4181 7247 4167 7245
      4185 7295 4189 7294 4190 7291 4197 7289
      4197 7300 4201 7300
TIME...MOT...LOC 2001Z 291DEG 31KT 4192 7284 

TORNADO...RADAR INDICATED
HAIL...2.00IN

$$

Sipprell

2 follow-up statements

761 
WWUS51 KBOX 152008
SVSBOX

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

CTC003-152030-
/O.CON.KBOX.TO.W.0002.000000T0000Z-180515T2030Z/
Hartford CT-
408 PM EDT TUE MAY 15 2018

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 430 PM EDT FOR
NORTHEASTERN HARTFORD COUNTY...
    
At 408 PM EDT, a severe thunderstorm capable of producing a tornado
was located over East Granby, or near Windsor, moving east at 35 mph.

HAZARD...Tornado and up to tennis ball size hail.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur. Tree damage is 
         likely.

This dangerous storm will be near...
  Windsor and Windsor Locks around 420 PM EDT.
  East Windsor around 425 PM EDT.
  Manchester, Vernon, South Windsor and Ellington around 430 PM EDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors or in
a vehicle, move to the closest substantial shelter and protect
yourself from flying debris.

&&

LAT...LON 4197 7250 4195 7249 4194 7251 4186 7252
      4186 7250 4181 7251 4181 7247 4174 7246
      4190 7287 4199 7282
TIME...MOT...LOC 2008Z 282DEG 30KT 4193 7276 

TORNADO...RADAR INDICATED
HAIL...2.50IN

$$

Sipprell

137 
WWUS51 KBOX 152024
SVSBOX

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

CTC003-152034-
/O.EXP.KBOX.TO.W.0002.000000T0000Z-180515T2030Z/
Hartford CT-
424 PM EDT TUE MAY 15 2018

...THE TORNADO WARNING FOR NORTHEASTERN HARTFORD COUNTY WILL EXPIRE
AT 430 PM EDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning will be allowed to expire.  However small
hail, gusty winds and heavy rain are still possible with this
thunderstorm.

A Tornado Watch remains in effect until 900 PM EDT for northern
Connecticut.

LAT...LON 4197 7250 4195 7249 4194 7251 4186 7252
      4186 7250 4181 7251 4181 7247 4174 7246
      4190 7287 4199 7282
TIME...MOT...LOC 2024Z 291DEG 31KT 4188 7260 

$$

Sipprell

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, 3:46 PM EDT	Severe Thunderstorm Warning	BOX	Capitol Planning Region	59 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

Nearby

Tornado Warnings in Connecticut, 2018 Every tornado warning in 2018 Tornadoes 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.