Alert archive / New Hampshire / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 2, NWS Boston/Norton, MA

May 7, 2011Hillsborough County, New Hampshire

NWS Boston/Norton, MA issued this severe thunderstorm warning at May 7, 2011, 12:48 PM EDT for Hillsborough County, New Hampshire. It was in force for 57 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: May 7, 2011, 12:48 PM EDT (16:48 UTC)
Expired: May 7, 2011, 1:45 PM EDT
In force: 57 min
Issued by: NWS Boston/Norton, MA
Area: Storm-based polygon

County Hillsborough County, NH

The radar

The Boston radar (KBOX), 111 km from the middle of the area, began a volume at 16:51 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 12:00Z, 4.8 hours before the alert went out and 146 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: 55 J/kg
Mixed-layer CIN: -166 J/kg
Mixed-layer LCL: 1294 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 57 m²/s²
0-3 km storm-relative helicity: 57 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.

999 
WUUS51 KBOX 071648
SVRBOX
NHC011-071745-
/O.NEW.KBOX.SV.W.0002.110507T1648Z-110507T1745Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TAUNTON MA
1248 PM EDT SAT MAY 7 2011

THE NATIONAL WEATHER SERVICE IN TAUNTON HAS ISSUED A

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

* UNTIL 145 PM EDT

* AT 1243 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS
  STORM WAS LOCATED 6 MILES SOUTHWEST OF BEDFORD...OR 9 MILES
  SOUTHWEST OF MANCHESTER...AND WAS MOVING NORTHEAST AT 10 MPH.

* THE SEVERE THUNDERSTORM WILL PASS NEAR BEDFORD AND 5 MILES
  SOUTH OF MANCHESTER.

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 7146 4293 7143 4293 7144 4291 7144
      4290 7144 4286 7159 4290 7161
TIME...MOT...LOC 1647Z 233DEG 10KT 4290 7157

$$
FIELD

The office that day

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

Issued	Product	Office	Counties	Lasted
May 7, 12:10 PM EDT	Special Weather Statement	BOX	Hillsborough	50 min
May 7, 12:31 PM EDT	Severe Thunderstorm Warning	BOX	Hillsborough	29 min
May 7, 12:41 PM EDT	Special Weather Statement	BOX	Hillsborough	49 min
May 7, 1:58 PM EDT	Special Weather Statement	BOX	Rockingham	62 min
May 7, 2:49 PM EDT	Special Weather Statement	BOX	Hillsborough	41 min

Nearby

Severe Thunderstorm Warnings in New Hampshire, 2011 Every severe thunderstorm warning in 2011

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.