Alert archive / Massachusetts / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 92, NWS Boston/Norton, MA

August 11, 2012Hillsborough County, New Hampshire; Middlesex County, Worcester County, Massachusetts

NWS Boston/Norton, MA issued this severe thunderstorm warning at Aug 11, 2012, 8:18 PM EDT for Hillsborough County, New Hampshire; Middlesex County, Worcester County, Massachusetts. It was in force for 30 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 11, 2012, 8:18 PM EDT (00:18 UTC)
Expired
Aug 11, 2012, 8:48 PM EDT
In force
30 min
Issued by
NWS Boston/Norton, MA
Area
Storm-based polygon

Counties Middlesex County, MA, Worcester County, MA, Hillsborough County, NH

The radar

The Boston radar (KBOX), 100 km from the middle of the area, began a volume at 00:20 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

Gray, ME (KGYX), launched 00:00Z, 0.3 hours before the alert went out and 164 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, Gray, ME at 00:00Z on 2012-08-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 280 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, Gray, ME at 00:00Z on 2012-08-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 29 square meters per square second.19395878Sfc1 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
280 J/kg
Mixed-layer CIN
-21 J/kg
Mixed-layer LCL
518 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
29 m²/s²
0-3 km storm-relative helicity
52 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3

Open this sounding in Storm Lab

The text

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

842 
WUUS51 KBOX 120018
SVRBOX
MAC017-027-NHC011-120100-
/O.NEW.KBOX.SV.W.0092.120812T0018Z-120812T0100Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TAUNTON MA
818 PM EDT SAT AUG 11 2012

THE NATIONAL WEATHER SERVICE IN TAUNTON HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTH CENTRAL WORCESTER COUNTY IN CENTRAL MASSACHUSETTS...
  THIS INCLUDES THE CITY OF FITCHBURG...
  NORTHWESTERN MIDDLESEX COUNTY IN SOUTHEAST MASSACHUSETTS...
  SOUTHEASTERN HILLSBOROUGH COUNTY IN SOUTHERN NEW HAMPSHIRE...
  THIS INCLUDES THE CITY OF NASHUA...

* UNTIL 900 PM EDT

* AT 818 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 ASHBURNHAM...OR NEAR
  FITCHBURG...AND WAS MOVING NORTHEAST AT 25 MPH.

* SOME LOCATIONS IN THE WARNING INCLUDE...ASHBY...LUNENBURG...NEW
  IPSWICH...GREENVILLE...TOWNSEND...MASON...BROOKLINE...PEPPERELL...
  HOLLIS...MILFORD...MERRIMACK...LITCHFIELD...HUDSON...BEDFORD AND
  AMHERST.

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 4297 7148 4293 7144 4284 7143 4283 7138
      4280 7136 4278 7135 4277 7131 4254 7185
      4269 7199 4271 7194 4271 7193 4272 7193
TIME...MOT...LOC 0018Z 237DEG 21KT 4263 7185

$$

KJC
1 follow-up statement
166 
WWUS51 KBOX 120048
SVSBOX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TAUNTON MA
848 PM EDT SAT AUG 11 2012

MAC017-027-NHC011-120059-
/O.CAN.KBOX.SV.W.0092.000000T0000Z-120812T0100Z/
MIDDLESEX MA-WORCESTER MA-HILLSBOROUGH NH-
848 PM EDT SAT AUG 11 2012

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN HILLSBOROUGH...
NORTH CENTRAL WORCESTER AND NORTHWESTERN MIDDLESEX COUNTIES IS
CANCELLED...

LAT...LON 4297 7148 4293 7144 4284 7143 4283 7138
      4280 7136 4278 7135 4277 7131 4254 7185
      4269 7199 4271 7194 4271 7193 4272 7193
TIME...MOT...LOC 0049Z 237DEG 21KT 4273 7164

$$

KJC

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 11, 8:13 PM EDTSpecial Weather StatementBOXHillsborough47 min
Aug 11, 8:42 PM EDTSpecial Weather StatementBOXCheshire63 min
Aug 12, 4:27 PM EDTSpecial Weather StatementBOXHillsborough33 min
Aug 12, 7:32 AM EDTAreal Flood AdvisoryBOXHampden, Hampshire, Worcester3 hr
Aug 12, 2:53 PM EDTSpecial Weather StatementBOXWorcester37 min
Aug 12, 3:26 PM EDTSpecial Weather StatementBOXWorcester64 min
Aug 12, 4:24 PM EDTAreal Flood AdvisoryBOXMiddlesex, Worcester55 min
Aug 12, 6:38 PM EDTSpecial Weather StatementBOXSuffolk22 min
Aug 12, 7:03 PM EDTAreal Flood AdvisoryBOXEssex39 min

Nearby

Severe Thunderstorm Warnings in Massachusetts, 2012Severe Thunderstorm Warnings in New Hampshire, 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.