Alert archive / Massachusetts / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 72, NWS Boston/Norton, MA

August 5, 2012Middlesex County, Worcester County, Massachusetts

NWS Boston/Norton, MA issued this severe thunderstorm warning at Aug 5, 2012, 4:38 PM EDT for Middlesex County, Worcester County, Massachusetts. It was in force for 47 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 5, 2012, 4:38 PM EDT (20:38 UTC)
Expired
Aug 5, 2012, 5:25 PM EDT
In force
47 min
Issued by
NWS Boston/Norton, MA
Area
Storm-based polygon

Counties Middlesex County, MA, Worcester County, MA

The radar

The Boston radar (KBOX), 71 km from the middle of the area, began a volume at 20:40 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.

The nearest sounding before it

Chatham, MA (KCHH), launched 12:00Z, 8.6 hours before the alert went out and 159 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 2012-08-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1615 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, Chatham, MA at 12:00Z on 2012-08-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 3 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
1615 J/kg
Mixed-layer CIN
-5 J/kg
Mixed-layer LCL
492 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
3 m²/s²
0-3 km storm-relative helicity
8 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.

379 
WUUS51 KBOX 052038
SVRBOX
MAC017-027-052130-
/O.NEW.KBOX.SV.W.0072.120805T2038Z-120805T2130Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TAUNTON MA
438 PM EDT SUN AUG 5 2012

THE NATIONAL WEATHER SERVICE IN TAUNTON HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EAST CENTRAL WORCESTER COUNTY IN CENTRAL MASSACHUSETTS...
  CENTRAL MIDDLESEX COUNTY IN NORTHEAST MASSACHUSETTS...

* UNTIL 530 PM EDT

* AT 436 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS
  OF 60 MPH.  THIS STORM WAS LOCATED NEAR CLINTON...OR 8 MILES
  SOUTHEAST OF LEOMINSTER...AND WAS MOVING NORTHEAST AT 30 MPH.

* SOME LOCATIONS IN THE WARNING INCLUDE...BOLTON...HARVARD...
  BOXBOROUGH...ACTON...LITTLETON...WESTFORD...CARLISLE AND
  CHELMSFORD.

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS AND LARGE HAIL...AS WELL
AS DEADLY LIGHTNING AND TORRENTIAL RAIN. GET TO SAFE SHELTER NOW...
INSIDE A STURDY BUILDING OR IN A VEHICLE. DO NOT SEEK SHELTER UNDER
TREES. IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE STRUCK BY
LIGHTNING. DRIVERS SHOULD BE ALERT FOR PONDING OF WATER AND AVOID
FLOODED ROADS.

&&

LAT...LON 4266 7141 4254 7129 4239 7166 4245 7172
TIME...MOT...LOC 2038Z 234DEG 23KT 4244 7166

$$

WTB
2 follow-up statements
500 
WWUS51 KBOX 052115
SVSBOX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TAUNTON MA
515 PM EDT SUN AUG 5 2012

MAC017-027-052130-
/O.CON.KBOX.SV.W.0072.000000T0000Z-120805T2130Z/
MIDDLESEX MA-WORCESTER MA-
515 PM EDT SUN AUG 5 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 530 PM EDT
FOR EAST CENTRAL WORCESTER AND CENTRAL MIDDLESEX COUNTIES...

AT 510 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN
EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR WESTFORD...OR 8 MILES
SOUTHWEST OF LOWELL...MOVING NORTHEAST AT 25 MPH.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
CHELMSFORD

LAT...LON 4266 7141 4254 7129 4239 7166 4245 7172
TIME...MOT...LOC 2115Z 234DEG 23KT 4258 7140

$$

WTB
068 
WWUS51 KBOX 052125
SVSBOX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TAUNTON MA
525 PM EDT SUN AUG 5 2012

MAC017-027-052135-
/O.CAN.KBOX.SV.W.0072.000000T0000Z-120805T2130Z/
MIDDLESEX MA-WORCESTER MA-
525 PM EDT SUN AUG 5 2012

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL WORCESTER AND
CENTRAL MIDDLESEX COUNTIES IS CANCELLED...

THUNDERSTORMS HAVE MOVED OUT OF THE WARNED AREA.


LAT...LON 4266 7141 4254 7129 4239 7166 4245 7172
TIME...MOT...LOC 2125Z 234DEG 23KT 4262 7133

$$

WTB

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 5, 4:03 AM EDTFlash Flood WatchBOXFranklin, Hampden, Hampshire19 hr
Aug 5, 4:08 AM EDTSmall Craft AdvisoryBOX27 hr
Aug 5, 2:02 PM EDTSpecial Weather StatementBOXHampden, Hampshire58 min
Aug 5, 3:03 PM EDTSevere Thunderstorm WarningBOXFranklin, Hampshire, Worcester42 min
Aug 5, 3:33 PM EDTSpecial Weather StatementBOXWorcester57 min
Aug 5, 4:20 PM EDTSevere Thunderstorm WarningBOXHampden40 min
Aug 5, 5:05 PM EDTSevere Thunderstorm WarningBOXHampden, Worcester40 min
Aug 5, 5:30 PM EDTSpecial Marine WarningBOX51 min
Aug 5, 5:46 PM EDTSevere Thunderstorm WarningBOXWorcester29 min
Aug 5, 7:52 PM EDTSpecial Weather StatementBOXHampden83 min

Nearby

Severe Thunderstorm Warnings in Massachusetts, 2012Every severe thunderstorm warning in 2012

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.