Alert archive / New Hampshire / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 113, NWS Boston/Norton, MA

September 18, 2012Cheshire County, Hillsborough County, New Hampshire

NWS Boston/Norton, MA issued this severe thunderstorm warning at Sep 18, 2012, 8:34 PM EDT for Cheshire County, Hillsborough County, New Hampshire. It was in force for 56 min. 3 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: Sep 18, 2012, 8:34 PM EDT (00:34 UTC)
Expired: Sep 18, 2012, 9:30 PM EDT
In force: 56 min
Issued by: NWS Boston/Norton, MA
Area: Storm-based polygon

Counties Cheshire County, NH, Hillsborough County, NH

The radar

The Boston radar (KBOX), 147 km from the middle of the area, began a volume at 00:37 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
Sep 18, 9:24 PM EDT	TSTM WND DMG	Hinsdale, NH	TREE DOWN ON RTE 119
Sep 18, 9:32 PM EDT	TSTM WND DMG	Winchester, NH	TREE DOWN ON RTE 10 NEAR SEMINARY ROAD
Sep 18, 9:34 PM EDT	TSTM WND DMG	Harrisville, NH	TREE AND WIRES DOWN ON CHURCH STREET

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
Sep 18, 7:54 PM EDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Albany, NY (KALY), launched 00:00Z, 0.6 hours before the alert went out and 141 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: 47 J/kg
Mixed-layer CIN: -10 J/kg
Mixed-layer LCL: 675 m above ground
0-6 km bulk shear: 67 kt
0-1 km storm-relative helicity: -4 m²/s²
0-3 km storm-relative helicity: 47 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.

262 
WUUS51 KBOX 190034
SVRBOX
NHC005-011-190130-
/O.NEW.KBOX.SV.W.0113.120919T0034Z-120919T0130Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TAUNTON MA
834 PM EDT TUE SEP 18 2012

THE NATIONAL WEATHER SERVICE IN TAUNTON HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CHESHIRE COUNTY IN SOUTHERN NEW HAMPSHIRE...
  THIS INCLUDES THE CITIES OF...KEENE...JAFFREY...
  WESTERN HILLSBOROUGH COUNTY IN SOUTHERN NEW HAMPSHIRE...

* UNTIL 930 PM EDT

* AT 830 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
  A LINE OF THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WINDS IN   
  EXCESS OF 60 MPH.  THESE STORMS WERE LOCATED ALONG A LINE
  EXTENDING ALONG THE CONNECTICUT RIVER...AND WERE MOVING NORTHEAST 
  AT 50 MPH.

* SOME LOCATIONS IN THE WARNING INCLUDE...    
  KEENE...JAFFREY...PETERBOROUGH AND ANTRIM.

WHILE NOT IMMEDIATELY LIKELY TONIGHT...THUNDERSTORMS CAN SOMETIMES 
PRODUCE A TORNADO. REMAIN CALM...BUT TAKE COVER NOW. GO TO AN 
INTERIOR ROOM ON THE LOWEST FLOOR OF A STURDY BUILDING. AVOID 
WINDOWS.

&&

LAT...LON 4312 7185 4315 7166 4306 7164 4306 7162
      4271 7185 4275 7248 4276 7252 4288 7256
      4292 7253 4295 7254 4301 7245 4305 7247
      4316 7246 4314 7238 4316 7238 4319 7216
      4314 7217 4313 7205 4319 7203 4321 7191
TIME...MOT...LOC 0030Z 217DEG 73KT 4315 7245 4177 7330

$$

WTB

1 follow-up statement

488 
WWUS51 KBOX 190110
SVSBOX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TAUNTON MA
910 PM EDT TUE SEP 18 2012

NHC005-011-190130-
/O.CON.KBOX.SV.W.0113.000000T0000Z-120919T0130Z/
CHESHIRE NH-HILLSBOROUGH NH-
910 PM EDT TUE SEP 18 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 930 PM EDT
FOR WESTERN HILLSBOROUGH AND CHESHIRE COUNTIES...

AT 906 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE A LINE OF SHOWERS AND THUNDERSTORMS CAPABLE OF PRODUCING 
DAMAGING WINDS IN EXCESS OF 60 MPH.  THESE STORMS WERE LOCATED ALONG 
A LINE EXTENDING FROM ALSTEAD TO HINSDALE...MOVING NORTHEAST AT 50 
MPH.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO 
KEENE...JAFFREY...RINDGE...PETERBOROUGH...FRANCESTOWN AND ANTRIM.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 300 AM EDT
WEDNESDAY MORNING FOR NORTHERN CONNECTICUT AND MASSACHUSETTS AND
SOUTHERN NEW HAMPSHIRE AND CENTRAL RHODE ISLAND.

&&

LAT...LON 4312 7185 4315 7166 4306 7164 4306 7162
      4271 7185 4275 7248 4276 7252 4288 7256
      4292 7253 4295 7254 4301 7245 4305 7247
      4316 7246 4314 7238 4316 7238 4319 7216
      4314 7217 4313 7205 4319 7203 4321 7191
TIME...MOT...LOC 0108Z 217DEG 73KT 4375 7179 4238 7267

$$

WTB

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 18, 8:52 PM EDT	Areal Flood Advisory	BOX	Cheshire, Hillsborough	5 hr
Sep 18, 9:31 PM EDT	Severe Thunderstorm Warning	BOX	Cheshire, Hillsborough	59 min
Sep 18, 10:16 PM EDT	Severe Thunderstorm Warning	BOX	Hillsborough	59 min
Sep 18, 11:16 PM EDT	Severe Thunderstorm Warning	BOX	Hillsborough	59 min
Sep 19, 3:41 AM EDT	Frost Advisory	BOX	Cheshire	28 hr

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.