Alert archive / New Hampshire / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 99, NWS Gray, ME

December 11, 20214 counties in New Hampshire

NWS Gray, ME issued this severe thunderstorm warning at Dec 11, 2021, 9:56 PM EST for 4 counties in New Hampshire. It was in force for 64 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
Dec 11, 2021, 9:56 PM EST (02:56 UTC)
Expired
Dec 11, 2021, 11:00 PM EST
In force
64 min
Issued by
NWS Gray, ME
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Cheshire County, NH, Hillsborough County, NH, Merrimack County, NH, Sullivan County, NH

The radar

The Albany radar (KENX), 146 km from the middle of the area, began a volume at 03:00 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

TimeReportWhereRemark
Dec 11, 10:35 PM ESTTSTM WND DMG2 Ne Winchester, NHTREE LIMBS DOWN ON POWER LINES NEAR FOREST LAKE.
Dec 11, 10:45 PM ESTTSTM WND DMG1 E Keene, NHTREE DOWN ON POWER LINE WASHINGTON ST.
Dec 11, 10:45 PM ESTTSTM WND DMG2 Nne Harrisville, NHTREE LIMBS DOWN ON POWER LINES NUBANUSIT RD NEAR CADY LN.

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

The nearest sounding before it

Albany, NY (KALY), launched 00:00Z, 2.9 hours before the alert went out and 124 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, Albany, NY at 00:00Z on 2021-12-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Albany, NY at 00:00Z on 2021-12-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 405 square meters per square second.1939587897117136Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
956 m above ground
0-6 km bulk shear
95 kt
0-1 km storm-relative helicity
405 m²/s²
0-3 km storm-relative helicity
481 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

334 
WUUS51 KGYX 120256
SVRGYX
NHC005-011-013-019-120400-
/O.NEW.KGYX.SV.W.0099.211212T0256Z-211212T0400Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Gray ME
956 PM EST Sat Dec 11 2021

The National Weather Service in Gray Maine has issued a

* Severe Thunderstorm Warning for...
  Southern Sullivan County in central New Hampshire...
  Cheshire County in southern New Hampshire...
  Western Hillsborough County in southern New Hampshire...
  Southwestern Merrimack County in central New Hampshire...

* Until 1100 PM EST.

* At 955 PM EST, severe thunderstorms were located along a line
  extending from near Claremont to near Walpole to 12 miles northwest
  of Hinsdale to 25 miles southwest of Chesterfield, moving east at
  70 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Locations impacted include...
  Keene, Jaffrey, Henniker, Peterborough, Hopkinton, Charlestown,
  Winchester, Antrim, Greenfield, Lyndeborough, Bradford, Dublin,
  Francestown, Bennington, Richmond, Harrisville, Nelson, Rindge,
  Walpole and Alstead.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4292 7252 4295 7253 4297 7248 4300 7244
      4305 7247 4308 7244 4310 7245 4312 7243
      4315 7246 4323 7243 4325 7244 4328 7176
      4313 7177 4271 7186 4273 7246 4276 7248
      4277 7251 4287 7256
TIME...MOT...LOC 0255Z 253DEG 60KT 4345 7231 4315 7248 4290 7270 4273
7291

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Legro
3 follow-up statements
875 
WWUS51 KGYX 120330
SVSGYX

Severe Weather Statement
National Weather Service Gray ME
1030 PM EST Sat Dec 11 2021

NHC005-011-013-019-120400-
/O.CON.KGYX.SV.W.0099.000000T0000Z-211212T0400Z/
Sullivan NH-Cheshire NH-Hillsborough NH-Merrimack NH-
1030 PM EST Sat Dec 11 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1100 PM EST
FOR SOUTHEASTERN SULLIVAN...CHESHIRE...WESTERN HILLSBOROUGH AND
SOUTHWESTERN MERRIMACK COUNTIES...

At 1030 PM EST, severe thunderstorms were located along a line
extending from 6 miles south of Ashland to Warner to near Antrim to
near Swanzey, moving east at 55 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Keene, Jaffrey, Henniker, Peterborough, Hopkinton, Winchester,
Antrim, Greenfield, Lyndeborough, Bradford, Dublin, Francestown,
Bennington, Richmond, Harrisville, Nelson, Gilsum, Marlborough,
Rindge and Windsor.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4328 7176 4313 7177 4271 7186 4273 7246
      4276 7248 4277 7251 4278 7251 4326 7216
TIME...MOT...LOC 0330Z 251DEG 41KT 4361 7164 4331 7182 4306 7204 4289
7225

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Legro
748 
WWUS51 KGYX 120347
SVSGYX

Severe Weather Statement
National Weather Service Gray ME
1047 PM EST Sat Dec 11 2021

NHC019-120357-
/O.CAN.KGYX.SV.W.0099.000000T0000Z-211212T0400Z/
Sullivan NH-
1047 PM EST Sat Dec 11 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN SULLIVAN COUNTY
IS CANCELLED...

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled.

LAT...LON 4313 7177 4271 7186 4272 7231 4295 7209
      4319 7188 4328 7176
TIME...MOT...LOC 0347Z 253DEG 60KT 4368 7130 4338 7148 4313 7171 4297
7192

$$

NHC005-011-013-120400-
/O.CON.KGYX.SV.W.0099.000000T0000Z-211212T0400Z/
Cheshire NH-Hillsborough NH-Merrimack NH-
1047 PM EST Sat Dec 11 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1100 PM EST
FOR SOUTHEASTERN CHESHIRE...WESTERN HILLSBOROUGH AND SOUTH CENTRAL
MERRIMACK COUNTIES...

At 1047 PM EST, severe thunderstorms were located along a line
extending from 6 miles southeast of Moultonborough to near Gilmanton
to near Weare to near Greenfield, moving east at 70 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Jaffrey, Henniker, Peterborough, Hopkinton, Antrim, Marlborough,
Greenfield, Lyndeborough, Dublin, Francestown, Bennington, Richmond,
Harrisville, Nelson, Rindge, Hancock, New Ipswich, Sharon, Deering
and Fitzwilliam.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4313 7177 4271 7186 4272 7231 4295 7209
      4319 7188 4328 7176
TIME...MOT...LOC 0347Z 253DEG 60KT 4368 7130 4338 7148 4313 7171 4297
7192

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Legro
965 
WWUS51 KGYX 120400
SVSGYX

Severe Weather Statement
National Weather Service Gray ME
1100 PM EST Sat Dec 11 2021

NHC005-011-013-120409-
/O.EXP.KGYX.SV.W.0099.000000T0000Z-211212T0400Z/
Cheshire NH-Hillsborough NH-Merrimack NH-
1100 PM EST Sat Dec 11 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN CHESHIRE...
WESTERN HILLSBOROUGH AND SOUTH CENTRAL MERRIMACK COUNTIES WILL EXPIRE
AT 1100 PM EST...
    
The storms which prompted the warning have moved out of the area.
Therefore, the warning will be allowed to expire.  However gusty
winds are still possible with these thunderstorms.

LAT...LON 4313 7177 4271 7186 4272 7231 4295 7209
      4319 7188 4328 7176
TIME...MOT...LOC 0359Z 253DEG 60KT 4373 7107 4343 7125 4318 7148 4302
7169

$$

Legro

The office that day

Everything else NWS Gray, ME issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 11, 9:39 PM ESTSpecial Weather StatementGYXCheshire, Sullivan51 min
Dec 11, 10:50 PM ESTSpecial Weather StatementGYXHillsborough, Merrimack, Rockingham, Strafford40 min
Dec 11, 11:36 PM ESTSpecial Weather StatementGYXRockingham, Strafford54 min

Nearby

Severe Thunderstorm Warnings in New Hampshire, 2021Every severe thunderstorm warning in 2021

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.