Alert archive / New Hampshire / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 45, NWS Boston/Norton, MA

July 17, 2012Hillsborough County, New Hampshire

NWS Boston/Norton, MA issued this severe thunderstorm warning at Jul 17, 2012, 8:03 PM EDT for Hillsborough County, New Hampshire. It was in force for 13 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: Jul 17, 2012, 8:03 PM EDT (00:03 UTC)
Expired: Jul 17, 2012, 8:16 PM EDT
In force: 13 min
Issued by: NWS Boston/Norton, MA
Area: Storm-based polygon

County Hillsborough County, NH

The radar

The Boston radar (KBOX), 119 km from the middle of the area, began a volume at 00:07 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
Jul 17, 8:11 PM EDT	TSTM WND DMG	Manchester, NH	TREE DOWN AT RIVER ROAD AND CASTLE DRIVE.

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

The nearest sounding before it

Gray, ME (KGYX), launched 00:00Z, 0.1 hours before the alert went out and 142 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: 1655 J/kg
Mixed-layer CIN: -66 J/kg
Mixed-layer LCL: 1489 m above ground
0-6 km bulk shear: 46 kt
0-1 km storm-relative helicity: 399 m²/s²
0-3 km storm-relative helicity: 447 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 9.5

Open this sounding in Storm Lab

The text

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

742 
WUUS51 KBOX 180003
SVRBOX
NHC011-180030-
/O.NEW.KBOX.SV.W.0045.120718T0003Z-120718T0030Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TAUNTON MA
803 PM EDT TUE JUL 17 2012

THE NATIONAL WEATHER SERVICE IN TAUNTON HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHEASTERN HILLSBOROUGH COUNTY IN SOUTHERN NEW HAMPSHIRE...

* UNTIL 830 PM EDT

* AT 758 PM EDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM
  CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS OF 60 MPH. THIS
  STORM WAS LOCATED NEAR GOFFSTOWN...OR 8 MILES NORTHWEST OF
  MANCHESTER...AND MOVING SOUTHEAST AT 30 MPH.

* LOCATIONS IMPACTED INCLUDE...
  MANCHESTER...BEDFORD...GOFFSTOWN...LITCHFIELD AND MERRIMACK. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS IN EXCESS OF 60 MPH...
DEADLY LIGHTNING AND VERY HEAVY RAIN. FOR YOUR PROTECTION...MOVE TO 
AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. HEAVY 
RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE INTO AREAS WHERE WATER 
COVERS THE ROAD.

&&

LAT...LON 4305 7151 4304 7148 4304 7146 4302 7145
      4301 7139 4294 7137 4293 7145 4284 7143
      4282 7149 4291 7159 4306 7166 4307 7165
      4305 7163 4307 7152
TIME...MOT...LOC 2358Z 313DEG 25KT 4308 7157 

$$

SIPPRELL

1 follow-up statement

322 
WWUS51 KBOX 180016
SVSBOX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TAUNTON MA
816 PM EDT TUE JUL 17 2012

NHC011-180026-
/O.CAN.KBOX.SV.W.0045.000000T0000Z-120718T0030Z/
HILLSBOROUGH NH-
816 PM EDT TUE JUL 17 2012

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN HILLSBOROUGH
COUNTY IS CANCELLED...

THE SEVERE THUNDERSTORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF 
THE WARNED AREA. THEREFORE THE WARNING HAS BEEN CANCELLED.

LAT...LON 4305 7151 4304 7148 4304 7145 4302 7145
      4301 7139 4294 7137 4293 7145 4284 7143
      4282 7148 4291 7159 4306 7166 4307 7165
      4305 7163 4307 7152
TIME...MOT...LOC 0016Z 313DEG 25KT 4308 7157 

$$

SIPPRELL

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 17, 8:46 PM EDT	Special Weather Statement	BOX	Cheshire	44 min
Jul 18, 12:54 PM EDT	Severe Thunderstorm Warning	BOX	Hillsborough	66 min

Nearby

Severe Thunderstorm Warnings in New Hampshire, 2012 Every 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.