Alert archive / Connecticut / Flash Flood Warnings in 2021

Flash Flood Warning 28, NWS Boston/Norton, MA

September 1, 2021Northeastern Connecticut Planning Region, Connecticut; Worcester County, Massachusetts

NWS Boston/Norton, MA issued this flash flood warning at Sep 1, 2021, 9:37 PM EDT for Northeastern Connecticut Planning Region, Connecticut; Worcester County, Massachusetts. It was in force for 10 hr. 15 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
Sep 1, 2021, 9:37 PM EDT (01:37 UTC)
Expired
Sep 2, 2021, 8:00 AM EDT
In force
10 hr
Issued by
NWS Boston/Norton, MA
Area
Storm-based polygon
Flood severity
None

Counties Northeastern Connecticut Planning Region, CT, Worcester County, MA

The radar

The Boston radar (KBOX), 67 km from the middle of the area, began a volume at 01:36 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 EDTFLOOD2 Ssw Worcester, MACAMBRIDGE STREET BRIDGE IS FLOODED/IMPASSABLE AND CLOSED.
Sep 2, 2:10 AM EDTFLOODDudley, MAWEST MAIN STREET FLOODED AND IMPASSABLE.
Sep 2, 2:11 AM EDTFLOODWorcester, MAMERRICK STREET AT PELHAM STREET CLOSED DUE TO FLOODING.
Sep 2, 2:30 AM EDTFLOODWorcester, MAPARTS OF SOUTHBRIDGE STREET CLOSED DUE TO FLOODING ALONG WITH QUINSIGAMOND AVENUE.
Sep 2, 2:34 AM EDTFLOOD1 Nne Webster, MAPART OF WORCESTER ROAD IS FLOODED AND IMPASSABLE.
Sep 2, 2:44 AM EDTFLOOD3 Nne Millbury, MASOUTHWEST CUTOFF AT GRAFTON STREET FLOODED AND IMPASSABLE. CAR STUCK IN THE STREET FLOODING.
Sep 2, 3:09 AM EDTFLOOD2 N Webster, MAROUTE 12 AT TANNER ROAD FLOODED AND IMPASSABLE.
Sep 2, 3:18 AM EDTFLOOD2 S Worcester, MACAR STUCK IN FLOODED WATERS AT THE INTERSECTION OF CAMBRIDGE STREET AND KANSAS STREET.
Sep 2, 6:20 AM EDTHEAVY RAIN 6.03Vernon, CT
Sep 2, 6:40 AM EDTHEAVY RAIN 5.35Tolland, CT
Sep 2, 6:48 AM EDTHEAVY RAIN 5.1Douglas, MA
Sep 2, 6:50 AM EDTHEAVY RAIN 5.84Coventry, CT
Sep 2, 7:00 AM EDTHEAVY RAIN 5.5Eastford, CT
Sep 2, 7:46 AM EDTHEAVY RAIN 5.08Auburn, MA
Sep 2, 7:55 AM EDTFLOODAndover, CTHOP RIVER OUT OF ITS BANKS IN ANDOVER, WHICH FLOODED BUNKER HILL, LONG HILL AND PARKER BRIDGE ROADS.

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, 1.6 hours before the alert went out and 149 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.

279 
WGUS51 KBOX 020137
FFWBOX
CTC013-015-MAC027-020930-
/O.NEW.KBOX.FF.W.0028.210902T0137Z-210902T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Boston/Norton MA
937 PM EDT Wed Sep 1 2021

The National Weather Service in Norton has issued a

* Flash Flood Warning for...
  Tolland County in northern Connecticut...
  Windham County in northern Connecticut...
  Southeastern Worcester County in central Massachusetts...

* Until 530 AM EDT Thursday.

* At 937 PM EDT, Doppler radar indicated heavy rain across the 
  warned area. Between 0.5 and 1.5 inches of rain have fallen. 
  Additional rainfall amounts of 3 to 5 inches are possible in the 
  warned area. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Flash flooding caused by heavy rain.

  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...
  Worcester, Manchester, Enfield, Marlborough, Shrewsbury, 
  Glastonbury, Vernon, Milford, Mansfield, South Windsor, Windham, 
  Plainfield, Westborough, Grafton, Willimantic, Killingly, Holden, 
  Webster, Southbridge and Ashland.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4171 7224 4161 7233 4160 7241 4181 7251
      4203 7251 4203 7214 4216 7213 4219 7189
      4223 7186 4228 7188 4234 7179 4233 7149
      4226 7151 4226 7159 4222 7160 4217 7148
      4202 7150 4201 7180 4164 7179 4166 7216

FLASH FLOOD...RADAR INDICATED

$$

Frank
3 follow-up statements
393 
WGUS71 KBOX 020653
FFSBOX

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

CTC013-015-MAC027-020930-
/O.CON.KBOX.FF.W.0028.000000T0000Z-210902T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Tolland CT-Windham CT-Worcester MA-
253 AM EDT Thu Sep 2 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 530 AM EDT EARLY THIS 
MORNING FOR TOLLAND, WINDHAM AND SOUTHEASTERN WORCESTER COUNTIES...

At 253 AM EDT, Doppler radar and automated rain gauges indicated 
that heavy rain was falling across the warned area. Mount Hope River 
at Warrenville is rising and is about to go into moderate flood. 
There are also reports of considerable street flooding with 
impassable roads in the Worcester and Dudley Massachusetts region.

Between 2 and 4.5 inches of rain have fallen. Additional rainfall 
amounts up to 1 inch are possible in the warned area. Flash flooding 
is ongoing or expected to begin shortly.

HAZARD...Flash flooding caused by heavy rain.

SOURCE...Radar and automated gauges.

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...
  Worcester, Manchester, Enfield, Marlborough, Shrewsbury, 
  Glastonbury, Vernon, Milford, Mansfield, South Windsor, Windham, 
  Plainfield, Westborough, Grafton, Willimantic, Killingly, Holden, 
  Webster, Southbridge and Ashland.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4171 7224 4161 7233 4160 7241 4181 7251
      4203 7251 4203 7214 4216 7213 4219 7189
      4223 7186 4228 7188 4234 7179 4233 7149
      4226 7151 4226 7159 4222 7160 4217 7148
      4202 7150 4201 7180 4164 7179 4166 7216

FLASH FLOOD...RADAR AND GAUGE INDICATED

$$

Frank
096 
WGUS71 KBOX 020753
FFSBOX

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

CTC013-015-MAC027-020930-
/O.CON.KBOX.FF.W.0028.000000T0000Z-210902T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Tolland CT-Windham CT-Worcester MA-
353 AM EDT Thu Sep 2 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 530 AM EDT EARLY THIS 
MORNING FOR TOLLAND, WINDHAM AND SOUTHEASTERN WORCESTER COUNTIES...

At 353 AM EDT, Doppler radar and automated rain gauges indicated 
that heavy rain was falling across the warned area.

Mount Hope River at Warrenville is rising and is about to go into 
moderate flood. There are also reports of considerable street 
flooding with impassable roads across Webster and especially 
Worcester. There are also cars reported to be stuck in flood waters 
in Worcester.

Between 2.5 and 4.5 inches of rain have fallen. Additional rainfall 
amounts up to 1 inch are possible in the warned area. Flash flooding 
is ongoing.

HAZARD...Flash flooding caused by heavy rain.

SOURCE...Radar and automated gauges.

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...
  Worcester, Manchester, Enfield, Marlborough, Shrewsbury, 
  Glastonbury, Vernon, Milford, Mansfield, South Windsor, Windham, 
  Plainfield, Westborough, Grafton, Willimantic, Killingly, Holden, 
  Webster, Southbridge and Ashland.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4171 7224 4161 7233 4160 7241 4181 7251
      4203 7251 4203 7214 4216 7213 4219 7189
      4223 7186 4228 7188 4234 7179 4233 7149
      4226 7151 4226 7159 4222 7160 4217 7148
      4202 7150 4201 7180 4164 7179 4166 7216

FLASH FLOOD...RADAR AND GAUGE INDICATED

$$

Frank
605 
WGUS51 KBOX 020900
FFWBOX
CTC013-015-MAC027-021200-
/O.EXT.KBOX.FF.W.0028.000000T0000Z-210902T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in Norton has extended the

* Flash Flood Warning for...
  Tolland County in northern Connecticut...
  Windham County in northern Connecticut...
  Southeastern Worcester County in central Massachusetts...

* Until 800 AM EDT.

* At 500 AM EDT, While the heavy rain has already exited the region, 
  widespread 3 to 5 inches of rain with localized higher amounts 
  fell overnight. Therefore, some roads may remain flooded and 
  impassable for the morning commute. This is especially true in 
  Worcester where significant urban flooding had occurred.

In addition, small rivers and streams continued to rise from the 
runoff. This includes the Mount Hope River at Warrenville which was 
in moderate flood and still rising. The Willimantic River at 
Coventry was still rising and currently just below moderate flood.



  HAZARD...Flash flooding caused by the earlier heavy rain.

  SOURCE...Automated gauges.

  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...
  Worcester, Manchester, Enfield, Marlborough, Shrewsbury, 
  Glastonbury, Vernon, Milford, Mansfield, South Windsor, Windham, 
  Plainfield, Westborough, Grafton, Willimantic, Killingly, Holden, 
  Webster, Southbridge and Ashland.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Do not drive through flooded roadways!

&&

LAT...LON 4171 7224 4161 7233 4160 7241 4181 7251
      4203 7251 4203 7214 4216 7213 4219 7189
      4223 7186 4228 7188 4234 7179 4233 7149
      4226 7151 4226 7159 4222 7160 4217 7148
      4202 7150 4201 7180 4164 7179 4166 7216

FLASH FLOOD...RADAR AND GAUGE INDICATED

$$

Frank

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 2, 1:51 AM EDTRiver Flood WarningBOXCapitol Planning Region26 hr
Sep 2, 1:51 AM EDTRiver Flood WarningBOXCapitol Planning Region66 hr
Sep 2, 1:51 AM EDTRiver Flood WarningBOXCapitol Planning Region45 hr
Sep 2, 7:25 AM EDTFlash Flood Warning Considerable damage threatBOXCapitol Planning Region, Northeastern Connecticut Planning Region6 hr
Sep 2, 7:43 AM EDTAreal Flood WarningBOXNortheastern Connecticut Planning Region6 hr
Sep 2, 8:20 AM EDTRiver Flood WarningBOXSoutheastern Connecticut Planning Region53 hr
Sep 2, 1:28 PM EDTAreal Flood WarningBOXCapitol Planning Region, Northeastern Connecticut Planning Region6 hr
Sep 2, 1:42 PM EDTAreal Flood WarningBOXNortheastern Connecticut Planning Region6 hr
Sep 1, 9:13 PM EDTFlash Flood WarningBOXHampden10 hr
Sep 1, 9:24 PM EDTSpecial Marine WarningBOX66 min
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, 12:08 AM EDTFlash Flood WarningBOXBarnstable, Dukes8 hr
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, 7:54 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, 5:59 PM EDTRiver Flood WarningBOXEssex, Middlesex25 hr

Nearby

Flash Flood Warnings in Connecticut, 2021Flash 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.