Alert archive / Connecticut / Severe Thunderstorm Warnings in 2013

Severe Thunderstorm Warning 2, NWS Boston/Norton, MA

May 21, 2013Northeastern Connecticut Planning Region, Connecticut

NWS Boston/Norton, MA issued this severe thunderstorm warning at May 21, 2013, 4:39 PM EDT for Northeastern Connecticut Planning Region, Connecticut. It was in force for 51 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
May 21, 2013, 4:39 PM EDT (20:39 UTC)
Expired
May 21, 2013, 5:30 PM EDT
In force
51 min
Issued by
NWS Boston/Norton, MA
Area
Storm-based polygon

County Northeastern Connecticut Planning Region, CT

The radar

The Boston radar (KBOX), 67 km from the middle of the area, began a volume at 20:39 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
May 21, 4:46 PM EDTHAIL 0.75Pomfret, CT

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.

IssuedProductOfficeLasted
May 21, 2:03 PM EDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 8.7 hours before the alert went out and 134 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, Brookhaven, NY at 12:00Z on 2013-05-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 267 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 12:00Z on 2013-05-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 59 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
267 J/kg
Mixed-layer CIN
-122 J/kg
Mixed-layer LCL
734 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
59 m²/s²
0-3 km storm-relative helicity
64 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

452 
WUUS51 KBOX 212039
SVRBOX
CTC015-212130-
/O.NEW.KBOX.SV.W.0002.130521T2039Z-130521T2130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TAUNTON MA
439 PM EDT TUE MAY 21 2013

THE NATIONAL WEATHER SERVICE IN TAUNTON HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHERN WINDHAM COUNTY IN NORTHERN CONNECTICUT...

* UNTIL 530 PM EDT

* AT 434 PM EDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM
  CAPABLE OF PRODUCING QUARTER SIZE HAIL AND DAMAGING WINDS IN EXCESS
  OF 60 MPH. THIS STORM WAS LOCATED NEAR POMFRET...OR 5 MILES
  SOUTHWEST OF PUTNAM...AND MOVING SOUTHEAST AT 20 MPH.

* LOCATIONS IMPACTED INCLUDE...
  PUTNAM...KILLINGLY...DANIELSON AND POMFRET. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS AND LARGE HAIL. GO INSIDE
TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. IF
DRIVING BE PREPARED FOR LOW VISIBILITY AND DO NOT DRIVE THROUGH
FLOODED ROADS.

&&

LAT...LON 4177 7185 4186 7209 4194 7207 4192 7180
TIME...MOT...LOC 2038Z 295DEG 16KT 4188 7200 

$$

JWD
2 follow-up statements
359 
WWUS51 KBOX 212103
SVSBOX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TAUNTON MA
503 PM EDT TUE MAY 21 2013

CTC015-212130-
/O.CON.KBOX.SV.W.0002.000000T0000Z-130521T2130Z/
WINDHAM CT-
503 PM EDT TUE MAY 21 2013

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 530 PM EDT
FOR NORTHERN WINDHAM COUNTY...

AT 500 PM EDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM CAPABLE
OF PRODUCING QUARTER SIZE HAIL AND DAMAGING WINDS IN EXCESS OF 60
MPH. THIS STORM WAS LOCATED NEAR POMFRET...OR 6 MILES SOUTHWEST OF
PUTNAM...MOVING SOUTHEAST AT 10 MPH.

AMATEUR RADIO OPERATORS REPORTED DIME SIZED HAIL WITH THIS STORM AT 
446 PM.

LOCATIONS IMPACTED INCLUDE...
PUTNAM...KILLINGLY...DANIELSON AND POMFRET. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS AND DESTRUCTIVE HAIL. GO
INSIDE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR
BUSINESS. DRIVERS SHOULD EXPECT POOR VISIBILITY AND AVOID FLOODED
ROADS.

&&

LAT...LON 4177 7185 4186 7209 4194 7207 4192 7180
TIME...MOT...LOC 2100Z 305DEG 10KT 4184 7198 

$$

JWD
020 
WWUS51 KBOX 212125
SVSBOX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TAUNTON MA
525 PM EDT TUE MAY 21 2013

CTC015-212134-
/O.EXP.KBOX.SV.W.0002.000000T0000Z-130521T2130Z/
WINDHAM CT-
525 PM EDT TUE MAY 21 2013

...THE SEVERE THUNDERSTORM WARNING FOR NORTHERN WINDHAM COUNTY WILL
EXPIRE AT 530 PM EDT...
                
THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER POSE AN IMMEDIATE THREAT TO LIFE OR PROPERTY.
THEREFORE THE WARNING WILL BE ALLOWED TO EXPIRE.  

EARLIER...SPOTTERS REPORTED DIME SIZED HAIL WITH THIS STORM. 

HEAVY RAIN IS STILL POSSIBLE WITH THIS THUNDERSTORM...WHICH WILL 
CAUSE MINOR FLOODING.

&&

LAT...LON 4177 7185 4186 7209 4194 7207 4192 7180
TIME...MOT...LOC 2124Z 295DEG 16KT 4184 7198 

$$

JWD

The office that day

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

IssuedProductOfficeCountiesLasted
May 21, 3:05 PM EDTSpecial Weather StatementBOX40 min
May 21, 4:17 PM EDTSpecial Weather StatementBOX43 min
May 21, 5:21 PM EDTAreal Flood AdvisoryBOXNortheastern Connecticut Planning Region114 min
May 21, 5:26 PM EDTSevere Thunderstorm WarningBOXNortheastern Connecticut Planning Region49 min
May 21, 6:03 PM EDTSpecial Weather StatementBOX42 min
May 21, 6:10 PM EDTSevere Thunderstorm WarningBOXCapitol Planning Region50 min
May 21, 6:16 PM EDTSevere Thunderstorm WarningBOXNortheastern Connecticut Planning Region44 min
May 21, 7:08 PM EDTSpecial Weather StatementBOX37 min
May 21, 7:20 PM EDTSpecial Weather StatementBOX55 min

Nearby

Severe Thunderstorm Warnings in Connecticut, 2013Every severe thunderstorm warning in 2013

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.