Alert archive / Massachusetts / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 3, NWS Boston/Norton, MA

May 4, 20184 counties in Massachusetts

NWS Boston/Norton, MA issued this severe thunderstorm warning at May 4, 2018, 9:35 PM EDT for 4 counties in Massachusetts. It was in force for 55 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 4, 2018, 9:35 PM EDT (01:35 UTC)
Expired
May 4, 2018, 10:30 PM EDT
In force
55 min
Issued by
NWS Boston/Norton, MA
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Franklin County, MA, Hampden County, MA, Hampshire County, MA, Worcester County, MA

The radar

The Albany radar (KENX), 94 km from the middle of the area, began a volume at 01:34 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
May 4, 6:20 PM EDTSevere Thunderstorm WatchSPC4 hr

The nearest sounding before it

Albany, NY (KALY), launched 00:00Z, 1.6 hours before the alert went out and 79 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 2018-05-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 360 joules per kilogram.LCLLFCEL10008507005003002001001 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 2018-05-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 441 square meters per square second.1939587897117Sfc1 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
360 J/kg
Mixed-layer CIN
-29 J/kg
Mixed-layer LCL
1408 m above ground
0-6 km bulk shear
85 kt
0-1 km storm-relative helicity
441 m²/s²
0-3 km storm-relative helicity
455 m²/s²
Significant tornado parameter
0.6
Supercell composite
6.3

Open this sounding in Storm Lab

The text

As transmitted.

442 
WUUS51 KBOX 050135
SVRBOX
MAC011-013-015-027-050230-
/O.NEW.KBOX.SV.W.0003.180505T0135Z-180505T0230Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Boston/Norton MA
935 PM EDT FRI MAY 4 2018

The National Weather Service in Boston/Norton has issued a

* Severe Thunderstorm Warning for...
  Northwestern Worcester County in central Massachusetts...
  Hampshire County in western Massachusetts...
  Franklin County in western Massachusetts...
  Western Hampden County in western Massachusetts...

* Until 1030 PM EDT.

* At 934 PM EDT, a line of strong to severe thunderstorms were 
  sweeping into western Massachusetts moving east at 50 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to trees and power lines.

* Locations impacted include...
  Westfield, Holyoke, Amherst, Northampton, Greenfield, Orange,
  Deerfield, South Hadley, Easthampton, Monroe, Athol, Winchendon,
  Montague, Templeton, Ashburnham, Southampton, Hadley, Sunderland,
  Hatfield and Northfield.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This is a DANGEROUS SITUATION. These storms have produced wind gusts 
upwards of 60 mph across the middle Hudson River Valley of NY as 
well as Berkshire County MA with isolated wind damage reports. SEEK 
SHELTER NOW inside a sturdy structure and stay away from windows! 

&&

LAT...LON 4215 7307 4215 7303 4231 7300 4233 7306
      4238 7307 4239 7301 4266 7295 4267 7300
      4270 7295 4270 7302 4274 7302 4271 7190
      4204 7295 4204 7306
TIME...MOT...LOC 0134Z 271DEG 43KT 4296 7234 4260 7289 4217 7361 

HAIL...<.75IN
WIND...60MPH
 
$$

Sipprell
2 follow-up statements
152 
WWUS51 KBOX 050201
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
1001 PM EDT FRI MAY 4 2018

MAC011-013-015-027-050230-
/O.CON.KBOX.SV.W.0003.000000T0000Z-180505T0230Z/
Worcester MA-Hampshire MA-Franklin MA-Hampden MA-
1001 PM EDT FRI MAY 4 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1030 PM EDT
FOR NORTHWESTERN WORCESTER...CENTRAL HAMPSHIRE...NORTHEASTERN
FRANKLIN AND NORTH CENTRAL HAMPDEN COUNTIES...

At 1000 PM EDT, Doppler radar indicated a line of strong to severe 
thunderstorms moving east at 50 mph across Franklin County MA.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to trees and power lines.

Locations impacted include...
Holyoke, Amherst, Northampton, Greenfield, Orange, Deerfield, South
Hadley, Easthampton, Athol, Winchendon, Montague, Templeton,
Ashburnham, Southampton, Hadley, Winchester, Sunderland, Hatfield,
Northfield and Williamsburg.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This is a DANGEROUS SITUATION. These storms have produced wind gusts 
upwards of 60 mph across Berkshire County MA with isolated wind 
damage reports of downed trees and power lines. SEEK SHELTER NOW 
inside a sturdy structure and stay away from windows!  

&&

LAT...LON 4245 7280 4273 7247 4271 7190 4219 7272
TIME...MOT...LOC 0200Z 273DEG 45KT 4270 7237 4258 7243 4246 7254 4241
7267

HAIL...<.75IN
WIND...60MPH
 
$$

Sipprell
562 
WWUS51 KBOX 050220
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
1020 PM EDT FRI MAY 4 2018

MAC011-013-015-027-050230-
/O.EXP.KBOX.SV.W.0003.000000T0000Z-180505T0230Z/
Worcester MA-Hampshire MA-Franklin MA-Hampden MA-
1020 PM EDT FRI MAY 4 2018

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN WORCESTER...
CENTRAL HAMPSHIRE...NORTHEASTERN FRANKLIN AND NORTH CENTRAL HAMPDEN
COUNTIES WILL EXPIRE AT 1030 PM EDT...
            
The storms which prompted the warning have weakened below severe
limits, and no longer pose an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However gusty
winds are still possible with these thunderstorms.

A Severe Thunderstorm Watch remains in effect until 200 AM EDT for
western Massachusetts.

LAT...LON 4245 7280 4273 7247 4271 7190 4219 7272
TIME...MOT...LOC 0220Z 271DEG 43KT 4270 7204 4258 7210 4246 7221 4241
7234

$$

Sipprell

The office that day

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

IssuedProductOfficeCountiesLasted
May 4, 9:04 PM EDTSpecial Weather StatementBOXFranklin41 min
May 4, 9:26 PM EDTSpecial Weather StatementBOXFranklin, Hampshire49 min
May 4, 10:14 PM EDTSpecial Weather StatementBOXWorcester46 min

Nearby

Severe Thunderstorm Warnings in Massachusetts, 2018Every severe thunderstorm warning in 2018

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.