Alert archive / Massachusetts / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 21, NWS Boston/Norton, MA

May 24, 2009Middlesex County, Norfolk County, Worcester County, Massachusetts

NWS Boston/Norton, MA issued this severe thunderstorm warning at May 24, 2009, 5:14 PM EDT for Middlesex County, Norfolk County, Worcester County, Massachusetts. It was in force for 31 min. 5 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
May 24, 2009, 5:14 PM EDT (21:14 UTC)
Expired
May 24, 2009, 5:45 PM EDT
In force
31 min
Issued by
NWS Boston/Norton, MA
Area
Storm-based polygon

Counties Middlesex County, MA, Norfolk County, MA, Worcester County, MA

The radar

The Boston radar (KBOX), 35 km from the middle of the area, began a volume at 21:15 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
May 24, 5:15 PM EDTHAIL 1Hopkinton, MA
May 24, 5:16 PM EDTHAIL 0.88Milford, MARELAYED FROM OKX
May 24, 5:20 PM EDTHAIL 1Ashland Ma,
May 24, 5:25 PM EDTHAIL 0.75Holliston, MAMIXED WITH SMALLER HAIL...LASTED 10 MINUTES.
May 24, 5:35 PM EDTTSTM WND DMGFramingham, MATREE AND WIRES DOWN ON HOLLIS STREET.

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

The nearest sounding before it

Chatham, MA (KCHH), launched 12:00Z, 9.2 hours before the alert went out and 129 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, Chatham, MA at 12:00Z on 2009-05-24Temperature 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, Chatham, MA at 12:00Z on 2009-05-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 88 square meters per square second.193958Sfc1 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
658 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
88 m²/s²
0-3 km storm-relative helicity
63 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.

000 
WUUS51 KBOX 242114
SVRBOX
MAC017-021-027-242145-
/O.NEW.KBOX.SV.W.0021.090524T2114Z-090524T2145Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TAUNTON MA
514 PM EDT SUN MAY 24 2009

THE NATIONAL WEATHER SERVICE IN TAUNTON HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EAST CENTRAL WORCESTER COUNTY IN CENTRAL MASSACHUSETTS...
  THIS INCLUDES THE CITY OF MILFORD...
  SOUTH CENTRAL MIDDLESEX COUNTY IN EASTERN MASSACHUSETTS...
  THIS INCLUDES THE CITIES OF...WALTHAM...NEWTON...FRAMINGHAM...
  NORTHWESTERN NORFOLK COUNTY IN EASTERN MASSACHUSETTS...

* UNTIL 545 PM EDT

* AT 513 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING GOLF BALL SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR
  HOPKINTON...OR NEAR MILFORD...AND MOVING EAST AT 35 MPH.

* SOME LOCATIONS IN THE WARNING INCLUDE... ASHLAND...HOLLISTON...
  MILLIS...SHERBORN...NATICK...MEDFIELD...DOVER...WELLESLEY...
  NEEDHAM...WESTWOOD...WESTON...NORWOOD AND DEDHAM

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS AND LARGE HAIL...IN
ADDITION TO DEADLY LIGHTNING AND VERY HEAVY RAIN. FOR YOUR SAFETY GO
INDOORS NOW AND STAY AWAY FROM WINDOWS. MINOR POOR DRAINAGE FLOODING
IS ALSO EXPECTED. DRIVERS SHOULD AVOID FLOODED ROADWAYS.

HAIL UP TO 1.75 INCHES IN DIAMETER HAS BEEN REPORTED WITH THIS 
STORM. IF YOU ARE IN THE PATH OF THE STORM...ACT NOW TO PROTECT LIFE 
AND PROPERTY. GET INDOORS NOW AND STAY AWAY FROM WINDOWS

LAT...LON 4219 7114 4212 7154 4226 7162 4239 7124
TIME...MOT...LOC 2114Z 256DEG 32KT 4221 7152

$$

WTB

The office that day

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

IssuedProductOfficeCountiesLasted
May 24, 1:55 PM EDTSevere Thunderstorm WarningBOXMiddlesex, Norfolk, Suffolk24 min
May 24, 2:21 PM EDTSpecial Marine WarningBOX165 days
May 24, 2:32 PM EDTSevere Thunderstorm WarningBOXWorcester43 min
May 24, 3:05 PM EDTSevere Thunderstorm WarningBOXNorfolk, Plymouth40 min
May 24, 3:07 PM EDTSpecial Marine WarningBOX13 min
May 24, 3:45 PM EDTSevere Thunderstorm WarningBOXPlymouth45 min
May 24, 4:01 PM EDTSpecial Marine WarningBOX59 min
May 24, 4:07 PM EDTSevere Thunderstorm WarningBOXHampden, Worcester18 min
May 24, 4:28 PM EDTSevere Thunderstorm WarningBOXMiddlesex, Norfolk, Suffolk32 min
May 24, 4:29 PM EDTSevere Thunderstorm WarningBOXWorcester15 min
May 24, 4:38 PM EDTSpecial Marine WarningBOX67 min
May 24, 4:46 PM EDTSevere Thunderstorm WarningBOXMiddlesex, Norfolk, Worcester44 min
May 24, 5:46 PM EDTSevere Thunderstorm WarningBOXHampden, Worcester19 min
May 24, 6:13 PM EDTSpecial Marine WarningBOX32 min
May 24, 6:27 PM EDTSpecial Marine WarningBOX63 min
May 24, 6:51 PM EDTSpecial Marine WarningBOX24 min

Nearby

Severe Thunderstorm Warnings in Massachusetts, 2009Every severe thunderstorm warning in 2009

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.