Alert archive / Massachusetts / Flash Flood Warnings in 2011

Flash Flood Warning 5, NWS Boston/Norton, MA

August 1, 2011Franklin County, Hampshire County, Worcester County, Massachusetts

NWS Boston/Norton, MA issued this flash flood warning at Aug 1, 2011, 1:41 PM EDT for Franklin County, Hampshire County, Worcester County, Massachusetts. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 1, 2011, 1:41 PM EDT (17:41 UTC)
Expired
Aug 1, 2011, 4:45 PM EDT
In force
3 hr
Issued by
NWS Boston/Norton, MA
Area
Storm-based polygon
Flood severity
None

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

The radar

The Boston radar (KBOX), 119 km from the middle of the area, began a volume at 17:41 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, 5.7 hours before the alert went out and 117 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 2011-08-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1159 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 12:00Z on 2011-08-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 96 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
1159 J/kg
Mixed-layer CIN
-92 J/kg
Mixed-layer LCL
824 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
96 m²/s²
0-3 km storm-relative helicity
116 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.

312 
WGUS51 KBOX 011741
FFWBOX
MAC011-015-027-012045-
/O.NEW.KBOX.FF.W.0005.110801T1741Z-110801T2045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE TAUNTON MA
141 PM EDT MON AUG 1 2011

THE NATIONAL WEATHER SERVICE IN TAUNTON HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EXTREME WEST CENTRAL WORCESTER COUNTY IN CENTRAL MASSACHUSETTS...
  SOUTHEASTERN FRANKLIN COUNTY IN WESTERN MASSACHUSETTS...
  EASTERN HAMPSHIRE COUNTY IN WESTERN MASSACHUSETTS...
  THIS INCLUDES THE CITY OF AMHERST...

* UNTIL 445 PM EDT

* AT 137 PM EDT...A THUNDERSTORM CAPABLE OF PRODUCING FLASH FLOODING 
WAS NEARLY STATIONARY OVER THE WARNED AREA. THIS INCLUDES BUT IS NOT 
LIMITED TO THE COMMUNITIES OF AMHERST...LEVERETT AND SHUTESBURY.  
RADAR ESTIMATES THAT UP TO 3 INCHES OF RAIN HAS FALLEN WITH THIS 
THUNDERSTORM.  ADDITIONAL HEAVY RAINS ARE ANTICIPATED...WITH FLASH 
FLOODING EXPECTED. 

THE MAIN THREAT IS URBAN FLASH FLOODING AND QUICK AND SUBSTANTIAL 
PONDING OF WATER IN LOW LYING AND POOR DRAINAGE AREAS. 
HOWEVER...SOME SMALL STREAM FLASH FLOODING IS ALSO POSSIBLE. 

FLASH FLOODING OF SMALL STREAMS AND URBAN AREAS IS OCCURRING OR
IMMINENT. THOSE NEAR STREAMS AND CREEKS...OR IN AREAS PRONE TO
FLOODING SHOULD MOVE TO HIGHER GROUND IMMEDIATELY. AVOID FLOODED
ROADS. THE WATER MAY BE TOO DEEP TO ALLOW VEHICLES TO CROSS SAFELY...
OR THE ROADWAY MAY BE UNDERMINED. TURN AROUND...DONT DROWN!

&&

LAT...LON 4248 7255 4247 7228 4224 7233 4229 7259

$$

NMB
3 follow-up statements
061 
WGUS71 KBOX 011802
FFSBOX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE TAUNTON MA
202 PM EDT MON AUG 1 2011

MAC011-015-027-012045-
/O.CON.KBOX.FF.W.0005.000000T0000Z-110801T2045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
WORCESTER MA-FRANKLIN MA-HAMPSHIRE MA-
202 PM EDT MON AUG 1 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 445 PM EDT FOR
EASTERN HAMPSHIRE...SOUTHEASTERN FRANKLIN AND EXTREME WEST CENTRAL
WORCESTER COUNTIES...

AT 155 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A 
CLUSTER OF THUNDERSTORMS OVER THE WARNING AREA.  THE STORM PRODUCING 
THE HEAVIEST RAIN HAD SLID SOUTH INTO THE SOUTHERN SECTIONS OF 
AMHERST...AS WELL AS BELCHERTOWN AND VICINITY. HOWEVER...ADDITIONAL 
LOCALLY HEAVY RAINS WERE ALSO OCCURRING JUST TO THE NORTH. LOCALLY 
HEAVY RAINS ARE EXPECTED IN THE WARNING AREA THROUGH 230 PM...AND AS 
A RESULT FLASH FLOODING IS EXPECTED. 

THE MAIN THREAT IS URBAN FLASH FLOODING AND QUICK AND SUBSTANTIAL 
PONDING OF WATER IN LOW LYING AND POOR DRAINAGE AREAS. 
HOWEVER...SOME SMALL STREAM FLASH FLOODING IS ALSO POSSIBLE. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY. MOVE TO HIGHER GROUND.

&&

LAT...LON 4248 7255 4247 7228 4224 7233 4229 7259

$$

NMB
656 
WGUS71 KBOX 011840
FFSBOX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE TAUNTON MA
240 PM EDT MON AUG 1 2011

MAC011-015-027-012045-
/O.CON.KBOX.FF.W.0005.000000T0000Z-110801T2045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
WORCESTER MA-FRANKLIN MA-HAMPSHIRE MA-
240 PM EDT MON AUG 1 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 445 PM EDT FOR
EASTERN HAMPSHIRE...SOUTHEASTERN FRANKLIN AND EXTREME WEST CENTRAL
WORCESTER COUNTIES...

AT 232 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE THAT THUNDERSTORMS WERE AFFECTING THE LEVERETT TO AMHERST 
AREA AND NEARBY COMMUNITIES. THESE STORMS ARE EXPECTED TO TRACK 
SOUTHEASTWARD THROUGH THE WARNING AREA THROUGH 3 PM. 

THE LOCALIZED HEAVY RAINS WILL BRING A CONTINUED THREAT FOR FLASH 
FLOODING.  THE MAIN THREAT IS SIGNIFICANT POOR DRAINAGE 
FLOODING...HOWEVER SMALL STREAM FLASH FLOODING IS ALSO A THREAT. 

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO SHUTESBURY...
PELHAM...LEVERETT AND AMHERST

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY. MOVE TO HIGHER GROUND.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1000 PM EDT
MONDAY EVENING FOR NORTHERN CONNECTICUT AND MASSACHUSETTS AND
SOUTHERN NEW HAMPSHIRE AND CENTRAL RHODE ISLAND.

&&

LAT...LON 4248 7255 4247 7228 4224 7233 4229 7259

$$

NMB
282 
WGUS71 KBOX 011932
FFSBOX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE TAUNTON MA
332 PM EDT MON AUG 1 2011

MAC011-015-027-012045-
/O.CON.KBOX.FF.W.0005.000000T0000Z-110801T2045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
WORCESTER MA-FRANKLIN MA-HAMPSHIRE MA-
332 PM EDT MON AUG 1 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 445 PM EDT FOR
EASTERN HAMPSHIRE...SOUTHEASTERN FRANKLIN AND EXTREME WEST CENTRAL
WORCESTER COUNTIES...

AT 327 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A THUNDERSTORM PRODUCING FLASH FLOODING OVER THE WARNED 
AREA. THE STRONGEST THUNDERSTORM WAS OVER THE BELCHERTOWN 
AREA...MOVING SLOWLY SOUTHEASTWARD.  THIS STORM IS CAPABLE OF 
PRODUCING TORRENTIAL RAINS. AS A RESULT...FLASH FLOODING REMAINS A 
THREAT. 

TO THE NORTHWEST...RECENT HEAVY RAINS MAY ALLOW FOR A CONTINUED 
PERIOD OF SIGNIFICANT PONDING OF WATER IN LOW LYING AND POOR 
DRAINAGE AREAS.  SOME SMALL STREAMS MAY ALSO RISE OUT OF THEIR 
BANKS. 

THERE IS THE POSSIBILITY THAT ADDITIONAL THUNDERSTORMS MAY AFFECT 
THE AREA AS THE LATE AFTERNOON AND EARLY EVENING WEAR ON. 

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO SHUTESBURY...
PELHAM...LEVERETT AND AMHERST.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY. MOVE TO HIGHER GROUND.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1000 PM EDT
MONDAY EVENING FOR NORTHERN CONNECTICUT AND MASSACHUSETTS AND
SOUTHERN NEW HAMPSHIRE AND CENTRAL RHODE ISLAND.

&&

LAT...LON 4248 7255 4247 7228 4224 7233 4229 7259

$$

NMB

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 1, 12:37 PM EDTSpecial Weather StatementBOXHampshire53 min
Aug 1, 1:24 PM EDTSpecial Weather StatementBOXHampshire51 min
Aug 1, 1:27 PM EDTAreal Flood AdvisoryBOXFranklin, Hampshire, Worcester3 hr
Aug 1, 1:34 PM EDTSevere Thunderstorm WarningBOXFranklin, Hampshire, Worcester19 min
Aug 1, 1:55 PM EDTSevere Thunderstorm WarningBOXHampden, Hampshire35 min
Aug 1, 2:03 PM EDTSpecial Weather StatementBOXFranklin42 min
Aug 1, 2:08 PM EDTSpecial Weather StatementBOXHampden52 min
Aug 1, 2:13 PM EDTSevere Thunderstorm WarningBOXHampden47 min
Aug 1, 2:19 PM EDTFlash Flood WarningBOXHampden, Hampshire, Worcester116 min
Aug 1, 2:19 PM EDTSevere Thunderstorm WarningBOXFranklin, Hampshire41 min
Aug 1, 3:01 PM EDTSpecial Weather StatementBOXWorcester59 min
Aug 1, 3:05 PM EDTSevere Thunderstorm WarningBOXHampden, Worcester17 min
Aug 1, 3:10 PM EDTSpecial Weather StatementBOXFranklin50 min
Aug 1, 3:14 PM EDTSevere Thunderstorm WarningBOXFranklin, Hampshire, Worcester38 min
Aug 1, 3:18 PM EDTSevere Thunderstorm WarningBOXFranklin, Worcester42 min
Aug 1, 3:30 PM EDTSevere Thunderstorm WarningBOXFranklin, Hampden, Hampshire, Worcester45 min
Aug 1, 3:33 PM EDTSpecial Weather StatementBOXHampden57 min
Aug 1, 3:40 PM EDTAreal Flood AdvisoryBOXFranklin, Worcester113 min
Aug 1, 3:41 PM EDTSevere Thunderstorm WarningBOXHampden49 min
Aug 1, 3:59 PM EDTSevere Thunderstorm WarningBOXFranklin, Worcester61 min
Aug 1, 4:07 PM EDTFlash Flood WarningBOXFranklin, Worcester82 min
Aug 1, 4:08 PM EDTSpecial Weather StatementBOXEssex67 min
Aug 1, 4:15 PM EDTAreal Flood AdvisoryBOXHampden3 hr
Aug 1, 4:31 PM EDTSevere Thunderstorm WarningBOXFranklin, Worcester27 min
Aug 1, 4:37 PM EDTSpecial Weather StatementBOXFranklin23 min
Aug 1, 4:42 PM EDTSevere Thunderstorm WarningBOXFranklin, Hampshire, Worcester63 min
Aug 1, 4:55 PM EDTAreal Flood AdvisoryBOXFranklin, Hampshire, Worcester3 hr
Aug 1, 5:29 PM EDTSpecial Weather StatementBOXFranklin31 min
Aug 1, 6:29 PM EDTSpecial Weather StatementBOXHampshire46 min

Nearby

Flash Flood Warnings in Massachusetts, 2011Every flash flood 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.