Alert archive / Massachusetts / Flash Flood Warnings in 2021

Flash Flood Warning 4, NWS Boston/Norton, MA

July 9, 20214 counties in Massachusetts; Kent County, Providence County, Rhode Island

NWS Boston/Norton, MA issued this flash flood warning at Jul 9, 2021, 9:11 AM EDT for 4 counties in Massachusetts; Kent County, Providence County, Rhode Island. It was in force for 7 hr. 9 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
Jul 9, 2021, 9:11 AM EDT (13:11 UTC)
Expired
Jul 9, 2021, 3:41 PM EDT
In force
7 hr
Issued by
NWS Boston/Norton, MA
Area
Storm-based polygon
Flood severity
None

Counties Bristol County, MA, Middlesex County, MA, Norfolk County, MA, Worcester County, MA, Kent County, RI, Providence County, RI

The radar

The Boston radar (KBOX), 29 km from the middle of the area, began a volume at 13:15 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
Jul 9, 11:47 AM EDTFLOODWorcester, MASOUTHGATE STREET BETWEEN SOUTHBRIDGE STREET AND GARDNER STREET IS CLOSED DUE TO FLOODING. REPORTED BY AMATEUR RADIO.
Jul 9, 12:14 PM EDTFLOODWorcester, MACAMBRIDGE STREET FROM QUINSIGAMOND AVE TO MCKEON ROAD CLOSED DUE TO FLOODING.
Jul 9, 12:22 PM EDTFLOODFramingham, MAGATES ROAD NEAR PARKER IS IMPASSABLE DUE TO FLOODING AND IS CLOSED. CAR STUCK IN STREET FLOODING AT ROUTE 9 AND ROUTE 126.
Jul 9, 12:24 PM EDTFLOODFramingham, MAWORCESTER ROAD/RT 9 NEAR RT 126 CLOSED DUE TO FLOODING. RAMPS ON CONCORD ST/RT 126 CONNECTING TO RT 9 ARE ALSO CLOSED.
Jul 9, 12:26 PM EDTFLOODWorcester, MASECTION OF GRAFTON STREET CLOSED DUE TO FLOODING. REPORTED BY AMATEUR RADIO.
Jul 9, 1:28 PM EDTFLOODWorcester, MAHIGGINS STREET AT EAMES ROAD FLOODED AND IMPASSABLE.
Jul 9, 1:47 PM EDTFLOODMillbury, MAROUTE 146 NORTHBOUND AT ROUTE 122A IS CLOSED DUE TO FLOODING. REPORTED BY AMATEUR RADIO.
Jul 9, 2:00 PM EDTFLOODWorcester, MAMEDIA REPORTS FLOODING ON ROUTE 146 IN WORCESTER WITH A PERSON ABANDONING HIS VAN. PICTURE ON SOCIAL MEDIA CONFIRMS.
Jul 9, 2:03 PM EDTFLOODWorcester, MAINTERSECTION OF SOUTHBRIDGE AND SOUTHGATE STREETS FLOODED WITH WATER BUBBLING UP OUT OF MANHOLE COVERS.

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

The nearest sounding before it

Albany, NY (KALY), launched 12:00Z, 1.2 hours before the alert went out and 215 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 2021-07-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3 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 2021-07-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 67 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
3 J/kg
Mixed-layer CIN
-156 J/kg
Mixed-layer LCL
764 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
67 m²/s²
0-3 km storm-relative helicity
88 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

104 
WGUS51 KBOX 091311
FFWBOX
MAC005-017-021-027-RIC003-007-092000-
/O.NEW.KBOX.FF.W.0004.210709T1311Z-210709T2000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Boston/Norton MA
911 AM EDT Fri Jul 9 2021

The National Weather Service in Norton has issued a

* Flash Flood Warning for...
  Southeastern Worcester County in central Massachusetts...
  Western Norfolk County in eastern Massachusetts...
  South Central Middlesex County in northeastern Massachusetts...
  West Central Bristol County in southeastern Massachusetts...
  Kent County in Rhode Island...
  Providence County in Rhode Island...

* Until 400 PM EDT Friday.

* At 911 AM EDT, Doppler radar indicated bands of moderate to heavy 
  rain passing through the Providence to Worcester corridor and 
  Worcester to Framingham Corridor, and surrounding communities. 
  Radar estimates between 0.5 and 1 inch of rain has fallen. 
  Additional rainfall amounts of 1 to 3 inches are expected in the 
  warned area during the next few hours. Flash flooding is expected 
  to begin shortly.

  HAZARD...Flash flooding caused by heavy rain.

  SOURCE...Radar.

  IMPACT...Flash flooding of small 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, Providence, Warwick, Cranston, Pawtucket, Framingham, 
  East Providence, Woonsocket, Marlborough, Shrewsbury, Coventry, 
  Cumberland, Natick, North Providence, Franklin, West Warwick, 
  Needham, Johnston, North Attleborough and Milford.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be aware of your surroundings and do not drive on flooded roads.

Hilly terrain can make low lying poor drainage areas particularly 
dangerous in heavy rain. Do not attempt to cross flooded roads. Find 
an alternate route.

&&

LAT...LON 4235 7192 4239 7133 4227 7130 4203 7133
      4174 7131 4175 7132 4177 7132 4175 7135
      4172 7134 4172 7131 4170 7131 4165 7141
      4165 7143 4163 7145 4163 7147 4161 7149
      4160 7178 4202 7180

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1 INCH IN 1 HOUR

$$

NB
2 follow-up statements
510 
WGUS71 KBOX 091508
FFSBOX

Flash Flood Statement
National Weather Service Boston/Norton MA
1108 AM EDT Fri Jul 9 2021

MAC005-017-021-027-RIC003-007-092000-
/O.CON.KBOX.FF.W.0004.000000T0000Z-210709T2000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Bristol MA-Middlesex MA-Norfolk MA-Worcester MA-Kent RI-Providence
RI-
1108 AM EDT Fri Jul 9 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 4 PM EDT THIS 
AFTERNOON FOR SOUTHEASTERN WORCESTER, WESTERN NORFOLK, SOUTH CENTRAL 
MIDDLESEX, WEST CENTRAL BRISTOL, KENT AND PROVIDENCE COUNTIES...

At 1108 AM EDT, Doppler radar indicated bands of moderate to heavy 
rain continued to cross through the warning area. As of 11 am, 
rainfall amounts ranged from around 1 inch to near 2 inches. 
Additional rainfall amounts of 1 to 2 inches are expected through 
early this afternoon, with localized higher amounts possible. Flash 
flooding is ongoing or expected to begin shortly.

HAZARD...Flash flooding caused by heavy rain.

SOURCE...Radar.

IMPACT...Flash flooding of small 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, Providence, Warwick, Cranston, Pawtucket, Framingham, 
  East Providence, Woonsocket, Marlborough, Shrewsbury, Coventry, 
  Cumberland, Natick, North Providence, Franklin, West Warwick, 
  Needham, Johnston, North Attleborough and Milford.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be aware of your surroundings and do not drive on flooded roads.

Hilly terrain can make low lying poor drainage areas particularly 
dangerous in heavy rain. Do not attempt to cross flooded roads. Find 
an alternate route.

&&

LAT...LON 4235 7192 4239 7133 4227 7130 4203 7133
      4174 7131 4175 7132 4177 7132 4175 7135
      4172 7134 4172 7131 4170 7131 4165 7141
      4165 7143 4163 7145 4163 7147 4161 7149
      4160 7178 4202 7180

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1 INCH IN 1 HOUR

$$

NB
467 
WGUS71 KBOX 091941
FFSBOX

Flash Flood Statement
National Weather Service Boston/Norton MA
341 PM EDT Fri Jul 9 2021

MAC005-017-021-027-RIC003-007-091951-
/O.CAN.KBOX.FF.W.0004.000000T0000Z-210709T2000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Bristol MA-Middlesex MA-Norfolk MA-Worcester MA-Kent RI-Providence
RI-
341 PM EDT Fri Jul 9 2021

...FLASH FLOOD WARNING FOR SOUTHEASTERN WORCESTER, WESTERN NORFOLK, 
SOUTH CENTRAL MIDDLESEX, WEST CENTRAL BRISTOL, KENT AND PROVIDENCE 
COUNTIES HAS BEEN REPLACED WITH A FLOOD WARNING...

The heavy rains from Tropical Storm Elsa have ended. However, a 
widespread 1.5 to 4 inches of rain fell across the region. While the 
significant flash flood threat is ending, areas of minor stream and 
river flooding are likely into this evening. Poor drainage 
floodwaters are not expected to worsen, but may take several more 
hours to fully recede. Please continue to heed any road closures.
closures.

LAT...LON 4235 7192 4239 7133 4227 7130 4203 7133
      4174 7131 4175 7132 4177 7132 4175 7135
      4172 7134 4172 7131 4170 7131 4165 7141
      4165 7143 4163 7145 4163 7147 4161 7149
      4160 7178 4202 7180

$$

NB

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 9, 8:19 AM EDTFlash Flood WarningBOXHampden, Hampshire6 hr
Jul 9, 9:32 AM EDTFlash Flood WarningBOXBristol, Essex, Middlesex, Norfolk, Plymouth, Suffolk6 hr
Jul 9, 12:19 PM EDTRiver Flood WarningBOXNorfolk, Suffolk4 hr
Jul 9, 12:19 PM EDTRiver Flood WarningBOXEssex8 hr
Jul 9, 12:19 PM EDTRiver Flood WarningBOXMiddlesex37 hr
Jul 9, 2:24 PM EDTAreal Flood WarningBOXHampden, Worcester8 hr
Jul 9, 3:24 PM EDTAreal Flood WarningBOXBristol, Essex, Middlesex, Norfolk, Plymouth, Suffolk5 hr
Jul 9, 3:41 PM EDTAreal Flood WarningBOXBristol, Middlesex, Norfolk, Worcester5 hr
Jul 9, 4:52 PM EDTSmall Craft AdvisoryBOX22 hr
Jul 9, 7:50 PM EDTSpecial Weather StatementBOXHampden40 min
Jul 9, 5:33 AM EDTRiver Flood WarningBOXKent, Providence21 hr

Nearby

Flash Flood Warnings in Massachusetts, 2021Flash Flood Warnings in Rhode Island, 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.