Alert archive / Massachusetts / Special Weather Statements in 2021

Special Weather Statement, NWS Boston/Norton, MA

April 21, 2021Franklin County, Massachusetts

NWS Boston/Norton, MA issued this special weather statement at Apr 21, 2021, 3:25 PM EDT for Franklin County, Massachusetts. It was in force for 50 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
Apr 21, 2021, 3:25 PM EDT (19:25 UTC)
Expired
Apr 21, 2021, 4:15 PM EDT
In force
50 min
Issued by
NWS Boston/Norton, MA

County Franklin County, MA

The radar

The Albany radar (KENX), 96 km from the middle of the area, began a volume at 19:28 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

Albany, NY (KALY), launched 12:00Z, 7.4 hours before the alert went out and 77 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 12:00Z on 2021-04-21Temperature 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 12:00Z on 2021-04-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 298 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
814 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
298 m²/s²
0-3 km storm-relative helicity
352 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

415 
WWUS81 KBOX 211925
SPSBOX

Special Weather Statement
National Weather Service Boston/Norton MA
325 PM EDT Wed Apr 21 2021
 
MAZ002-003-008-212015-
Western Franklin MA-Western Hampshire MA-Eastern Franklin MA-
325 PM EDT Wed Apr 21 2021

...STRONG THUNDERSTORMS IN NORTHWEST MASSACHUSETTS...

At 324 PM EDT, Doppler radar was tracking a strong thunderstorm over
Hawley, or 12 miles southeast of North Adams, moving northeast at 30
mph.

Pea size hail and winds in excess of 40 mph will accompany this
storm. Some locations may see a small accumulation of hail.

Locations impacted include...
Bernardston, Buckland, Shelburne, Ashfield, Colrain, Charlemont,
Cummington, Leyden, Heath, Plainfield, Rowe and Hawley.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Get indoors when this storm approaches. Winds may be strong enough to
produce minor damage, such as a few downed branches.

&&

LAT...LON 4263 7295 4267 7296 4274 7289 4273 7251
      4247 7293 4252 7297 4256 7298
TIME...MOT...LOC 1924Z 232DEG 25KT 4256 7293 

$$

JWD

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 21, 2:15 PM EDTSpecial Weather StatementBOXFranklin, Hampden, Hampshire, Worcester90 min
Apr 21, 3:17 PM EDTSevere Thunderstorm WarningBOXHampden, Hampshire58 min
Apr 21, 4:11 PM EDTSpecial Weather StatementBOXWorcester49 min
Apr 21, 4:13 PM EDTFreeze WatchBOXBristol, Norfolk, Plymouth24 hr
Apr 21, 4:42 PM EDTSpecial Weather StatementBOXWorcester48 min
Apr 21, 5:26 PM EDTSpecial Weather StatementBOXEssex, Norfolk, Suffolk49 min
Apr 21, 4:13 PM EDTFreeze WarningBOXKent, Providence14 hr

Nearby

Special Weather Statements in Massachusetts, 2021Every special weather statement 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.