Alert archive / Massachusetts / Flash Flood Warnings in 2021

Flash Flood Warning 34, NWS Boston/Norton, MA

September 2, 2021Barnstable County, Dukes County, Massachusetts

NWS Boston/Norton, MA issued this flash flood warning at Sep 2, 2021, 12:08 AM EDT for Barnstable County, Dukes County, Massachusetts. It was in force for 8 hr. 1 report 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
Sep 2, 2021, 12:08 AM EDT (04:08 UTC)
Expired
Sep 2, 2021, 8:00 AM EDT
In force
8 hr
Issued by
NWS Boston/Norton, MA
Area
Storm-based polygon
Flood severity
None

Counties Barnstable County, MA, Dukes County, MA

The radar

The Boston radar (KBOX), 54 km from the middle of the area, began a volume at 04:08 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
Sep 2, 1:55 AM EDTFLOODBourne, MAROTARY FLOODED WITH 2 CARS STUCK IN FLOOD WATERS.

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

The nearest sounding before it

Brookhaven, NY (KOKX), launched 00:00Z, 4.1 hours before the alert went out and 203 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, Brookhaven, NY at 00:00Z on 2021-09-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 123 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, Brookhaven, NY at 00:00Z on 2021-09-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 279 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
123 J/kg
Mixed-layer CIN
-47 J/kg
Mixed-layer LCL
512 m above ground
0-6 km bulk shear
53 kt
0-1 km storm-relative helicity
279 m²/s²
0-3 km storm-relative helicity
456 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.2

Open this sounding in Storm Lab

The text

As transmitted.

453 
WGUS51 KBOX 020408
FFWBOX
MAC001-007-021200-
/O.NEW.KBOX.FF.W.0034.210902T0408Z-210902T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Boston/Norton MA
1208 AM EDT Thu Sep 2 2021

The National Weather Service in Norton has issued a

* Flash Flood Warning for...
  Barnstable County in southeastern Massachusetts...
  Dukes County in southeastern Massachusetts...

* Until 800 AM EDT Thursday.

* At 1208 AM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 3 inches of rain 
  have fallen. Additional rainfall amounts of 1 to 2 inches are 
  possible in the warned area. Flash flooding is ongoing or expected 
  to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Barnstable, Falmouth, Brewster, Marion, Oak Bluffs, Edgartown, 
  Tisbury, Aquinnah, Yarmouth, Wareham, Sandwich, Bourne, Dennis, 
  Mashpee, West Tisbury, Chilmark, Gosnold and Hyannis.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 4140 7097 4152 7072 4159 7065 4171 7073
      4167 7064 4171 7071 4171 7072 4173 7068
      4171 7065 4175 7062 4175 7063 4180 7053
      4175 7012 4122 7051

FLASH FLOOD...RADAR INDICATED

$$

HF
3 follow-up statements
911 
WGUS71 KBOX 020525
FFSBOX

Flash Flood Statement
National Weather Service Boston/Norton MA
125 AM EDT Thu Sep 2 2021

MAC001-007-021200-
/O.CON.KBOX.FF.W.0034.000000T0000Z-210902T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Barnstable MA-Dukes MA-
125 AM EDT Thu Sep 2 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 8 AM EDT THIS MORNING 
FOR BARNSTABLE AND DUKES COUNTIES...

At 125 AM EDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 2 and 4 inches of rain have 
fallen. Additional rainfall amounts of 1 to 3 inches are possible in 
the warned area. Flash flooding is ongoing.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar.

IMPACT...Flash flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other poor
         drainage and low-lying areas.

Some locations that will experience flash flooding include...
  Barnstable, Falmouth, Brewster, Marion, Oak Bluffs, Edgartown, 
  Tisbury, Aquinnah, Yarmouth, Wareham, Sandwich, Bourne, Dennis, 
  Mashpee, West Tisbury, Chilmark, Gosnold and Hyannis.

At 110 AM, Multiple cars were stuck in flood waters on Main street 
at Davis straights.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

&&

LAT...LON 4140 7097 4152 7072 4159 7065 4171 7073
      4167 7064 4171 7071 4171 7072 4173 7068
      4171 7065 4175 7062 4175 7063 4180 7053
      4175 7012 4122 7051

FLASH FLOOD...RADAR INDICATED

$$

Frank
273 
WGUS71 KBOX 020537
FFSBOX

Flash Flood Statement
National Weather Service Boston/Norton MA
137 AM EDT Thu Sep 2 2021

MAC001-007-021200-
/O.CON.KBOX.FF.W.0034.000000T0000Z-210902T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Barnstable MA-Dukes MA-
137 AM EDT Thu Sep 2 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 8 AM EDT THIS MORNING 
FOR BARNSTABLE AND DUKES COUNTIES...

At 137 AM EDT, Trained weather spotters reported thunderstorms 
producing heavy rain across the warned area. Between 2 and 4 inches 
of rain have fallen. Additional rainfall amounts of 1 to 3 inches 
are possible in the warned area. Flash flooding is ongoing or 
expected to begin shortly.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Trained spotters reported.

IMPACT...Flash flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other poor
         drainage and low-lying areas.

Some locations that will experience flash flooding include...
  Barnstable, Falmouth, Brewster, Marion, Oak Bluffs, Edgartown, 
  Tisbury, Aquinnah, Yarmouth, Wareham, Sandwich, Bourne, Dennis, 
  Mashpee, West Tisbury, Chilmark, Gosnold and Hyannis.

At 1218 AM in New Bedford...West Rodney Boulevard from 160 West 
Rodney Boulevard to Aquidneck street is closed due to flooding with 
water going across the road like a river. Cove Road closed from 
Stapleton to County Street. A few flooded basements have also been 
reported in New Bedford.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

&&

LAT...LON 4140 7097 4152 7072 4159 7065 4171 7073
      4167 7064 4171 7071 4171 7072 4173 7068
      4171 7065 4175 7062 4175 7063 4180 7053
      4175 7012 4122 7051

FLASH FLOOD...OBSERVED

$$

Frank
416 
WGUS71 KBOX 020847
FFSBOX

Flash Flood Statement
National Weather Service Boston/Norton MA
447 AM EDT Thu Sep 2 2021

MAC001-007-021200-
/O.CON.KBOX.FF.W.0034.000000T0000Z-210902T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Barnstable MA-Dukes MA-
447 AM EDT Thu Sep 2 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 8 AM EDT THIS MORNING 
FOR BARNSTABLE AND DUKES COUNTIES...

At 447 AM EDT, A cluster of thunderstorms produced flash flooding 
earlier this morning across the Falmouth to Hyannis corridor. 
Another cluster of very heavy rainfall will move int the region 
shortly. This will result in more flash flooding between 5 and 730 
am this morning. Between 2.5 and 4.5 inches of rain have fallen. 
Additional rainfall amounts of 1 to 3 inches are possible in the 
warned area. Flash flooding is already occurring.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Trained spotters reported.

IMPACT...Flash flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other poor
         drainage and low-lying areas.

Some locations that will experience flash flooding include...
  Barnstable, Falmouth, Brewster, Marion, Oak Bluffs, Edgartown, 
  Tisbury, Aquinnah, Yarmouth, Wareham, Sandwich, Bourne, Dennis, 
  Mashpee, West Tisbury, Chilmark, Gosnold and Hyannis.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 4140 7097 4152 7072 4159 7065 4171 7073
      4167 7064 4171 7071 4171 7072 4173 7068
      4171 7065 4175 7062 4175 7063 4180 7053
      4175 7012 4122 7051

FLASH FLOOD...OBSERVED

$$

Frank

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 1, 9:13 PM EDTFlash Flood WarningBOXHampden10 hr
Sep 1, 9:24 PM EDTSpecial Marine WarningBOX66 min
Sep 1, 9:37 PM EDTFlash Flood WarningBOXWorcester10 hr
Sep 1, 10:01 PM EDTFlash Flood WarningBOXEssex, Middlesex, Norfolk, Suffolk8 hr
Sep 1, 10:32 PM EDTFlash Flood WarningBOXBristol, Norfolk, Plymouth10 hr
Sep 1, 10:45 PM EDTSpecial Marine WarningBOX45 min
Sep 1, 10:57 PM EDTFlash Flood WarningBOXFranklin, Hampshire, Middlesex, Worcester8 hr
Sep 1, 11:02 PM EDTFlash Flood WarningBOXEssex, Middlesex8 hr
Sep 1, 11:21 PM EDTTornado WarningBOXBarnstable, Bristol, Dukes, Plymouth54 min
Sep 1, 11:24 PM EDTSpecial Marine WarningBOX66 min
Sep 1, 11:32 PM EDTSpecial Marine WarningBOX58 min
Sep 1, 11:32 PM EDTSpecial Marine WarningBOX58 min
Sep 1, 11:56 PM EDTTornado WarningBOXBarnstable, Dukes49 min
Sep 2, 12:20 AM EDTSpecial Marine WarningBOX55 min
Sep 2, 12:22 AM EDTTornado WarningBOXDukes53 min
Sep 2, 12:25 AM EDTSpecial Marine WarningBOX65 min
Sep 2, 12:45 AM EDTTornado WarningBOXBarnstable, Dukes60 min
Sep 2, 1:07 AM EDTSpecial Marine WarningBOX83 min
Sep 2, 1:15 AM EDTTornado WarningBOXDukes28 min
Sep 2, 1:51 AM EDTRiver Flood WarningBOXWorcester31 hr
Sep 2, 1:56 AM EDTTornado WarningBOXBarnstable26 min
Sep 2, 2:34 AM EDTFlash Flood Warning Considerable damage threatBOXBristol, Plymouth6 hr
Sep 2, 3:42 AM EDTRiver Flood WarningBOXNorfolk, Suffolk11 hr
Sep 2, 5:14 AM EDTSpecial Marine WarningBOX46 min
Sep 2, 5:26 AM EDTFlash Flood Warning Considerable damage threatBOXBarnstable, Bristol, Dukes, Plymouth3 hr
Sep 2, 5:30 AM EDTRiver Flood WarningBOXMiddlesex22 hr
Sep 2, 5:49 AM EDTSpecial Marine WarningBOX42 min
Sep 2, 6:02 AM EDTFlash Flood WarningBOXEssex, Middlesex, Norfolk, Suffolk3 hr
Sep 2, 6:14 AM EDTSpecial Marine WarningBOX25 min
Sep 2, 6:50 AM EDTAreal Flood WarningBOXFranklin, Hampden, Hampshire, Middlesex, Worcester6 hr
Sep 2, 7:04 AM EDTAreal Flood WarningBOXBristol, Essex, Middlesex, Norfolk, Plymouth, Suffolk and 1 more11 hr
Sep 2, 7:25 AM EDTFlash Flood Warning Considerable damage threatBOXHampden, Hampshire, Worcester6 hr
Sep 2, 7:43 AM EDTAreal Flood WarningBOXBristol, Norfolk, Plymouth, Worcester6 hr
Sep 2, 7:54 AM EDTAreal Flood WarningBOXBarnstable, Dukes, Plymouth6 hr
Sep 2, 8:14 AM EDTRiver Flood WarningBOXHampden, Hampshire13 hr
Sep 2, 8:20 AM EDTRiver Flood WarningBOXWorcester32 hr
Sep 2, 8:20 AM EDTRiver Flood WarningBOXMiddlesex, Worcester60 hr
Sep 2, 9:25 AM EDTRiver Flood WarningBOXBristol, Plymouth64 hr
Sep 2, 10:40 AM EDTSmall Craft AdvisoryBOX17 hr
Sep 2, 12:51 PM EDTAreal Flood WarningBOXFranklin, Hampden, Hampshire, Middlesex, Norfolk, Worcester6 hr
Sep 2, 1:28 PM EDTAreal Flood WarningBOXHampden6 hr
Sep 2, 1:42 PM EDTAreal Flood WarningBOXBristol, Norfolk, Plymouth, Worcester6 hr
Sep 2, 5:59 PM EDTRiver Flood WarningBOXEssex, Middlesex25 hr

Nearby

Flash Flood Warnings in Massachusetts, 2021Every flash flood 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.