Alert archive / Massachusetts / Flash Flood Warnings in 2026

Flash Flood Warning 13, NWS Boston/Norton, MA

September 13, 2026Bristol County, Plymouth County, Massachusetts

NWS Boston/Norton, MA issued this flash flood warning at Sep 13, 2026, 10:59 AM EDT for Bristol County, Plymouth County, Massachusetts. It was in force for 3 hr. 2 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 13, 2026, 10:59 AM EDT (14:59 UTC)
Expired
Sep 13, 2026, 2:00 PM EDT
In force
3 hr
Issued by
NWS Boston/Norton, MA
Area
Storm-based polygon
Flood severity
None

Counties Bristol County, MA, Plymouth County, MA

The radar

The Boston radar (KBOX), 39 km from the middle of the area, began a volume at 14:58 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 13, 11:30 AM EDTFLASH FLOOD1 E New Bedford, MAIn New Bedford, North Front Street was closed from Coggeshall St to the fish houses due to flooding. Relayed by amateur radio.
Sep 13, 11:37 AM EDTFLASH FLOOD1 W Acushnet, MAIn New Bedford, Belleville Ave was flooded and impassable. Relayed by amateur radio.

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 12:00Z, 3.0 hours before the alert went out and 187 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 12:00Z on 2026-09-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 677 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 12:00Z on 2026-09-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 103 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
677 J/kg
Mixed-layer CIN
-4 J/kg
Mixed-layer LCL
475 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
103 m²/s²
0-3 km storm-relative helicity
115 m²/s²
Significant tornado parameter
0.4
Supercell composite
2.6

Open this sounding in Storm Lab

The text

As transmitted.

855 
WGUS51 KBOX 131459
FFWBOX
MAC005-023-131800-
/O.NEW.KBOX.FF.W.0013.260913T1459Z-260913T1800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Boston/Norton MA
1059 AM EDT Sun Sep 13 2026

The National Weather Service in Norton has issued a

* Flash Flood Warning for...
  Southeastern Bristol County in southeastern Massachusetts...
  South Central Plymouth County in southeastern Massachusetts...

* Until 200 PM EDT.

* At 1059 AM EDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Between 1 and 1.5 inches of rain
  have fallen. The expected rainfall rate is 1 to 2 inches in 1 hour.
  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...Radar indicated.

  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...
  New Bedford, Fall River, Dartmouth, Marion, Wareham, Fairhaven,
  Acushnet, Freetown, Mattapoisett and Rochester.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4151 7101 4177 7103 4178 7079 4177 7069
      4158 7081

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL RATE...1-2 INCHES IN 1 HOUR

$$

FT
3 follow-up statements
467 
WGUS71 KBOX 131543
FFSBOX

Flash Flood Statement
National Weather Service Boston/Norton MA
1143 AM EDT Sun Sep 13 2026

MAC005-023-131800-
/O.CON.KBOX.FF.W.0013.000000T0000Z-260913T1800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Bristol MA-Plymouth MA-
1143 AM EDT Sun Sep 13 2026

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 2 PM EDT THIS
AFTERNOON FOR SOUTHEASTERN BRISTOL AND SOUTH CENTRAL PLYMOUTH
COUNTIES...

At 1143 AM EDT, local law enforcement reported thunderstorms
producing heavy rain across the warned area. Between 1 and 2 inches
of rain have fallen. The expected rainfall rate is 1 to 2 inches in 1
hour. 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...Law enforcement 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...
  New Bedford, Fall River, Dartmouth, Marion, Wareham, Fairhaven,
  Acushnet, Freetown, Mattapoisett and Rochester.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

Please report observed flooding to local emergency services or law
enforcement and request they pass this information to the National
Weather Service when you can do so safely.

&&

LAT...LON 4177 7103 4151 7101 4158 7081 4177 7069
      4178 7079

FLASH FLOOD...OBSERVED
EXPECTED RAINFALL RATE...1-2 INCHES IN 1 HOUR

$$

FT
222 
WGUS71 KBOX 131625
FFSBOX

Flash Flood Statement
National Weather Service Boston/Norton MA
1225 PM EDT Sun Sep 13 2026

MAC005-023-131800-
/O.CON.KBOX.FF.W.0013.000000T0000Z-260913T1800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Bristol MA-Plymouth MA-
1225 PM EDT Sun Sep 13 2026

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 2 PM EDT THIS
AFTERNOON FOR SOUTHEASTERN BRISTOL AND SOUTH CENTRAL PLYMOUTH
COUNTIES...

At 1225 PM EDT, gauge reports indicated thunderstorms producing heavy
rain across the warned area. Between 1.5 and 2.5 inches of rain have
fallen. The expected rainfall rate is 1 to 2 inches in 1 hour.
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...Gauges 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...
  New Bedford, Fall River, Dartmouth, Marion, Wareham, Fairhaven,
  Acushnet, Freetown, Mattapoisett and Rochester.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

Please report observed flooding to local emergency services or law
enforcement and request they pass this information to the National
Weather Service when you can do so safely.

&&

LAT...LON 4177 7103 4151 7101 4158 7081 4177 7069
      4178 7079

FLASH FLOOD...GAUGE INDICATED
EXPECTED RAINFALL RATE...1-2 INCHES IN 1 HOUR

$$

FT
959 
WGUS71 KBOX 131753
FFSBOX

Flash Flood Statement
National Weather Service Boston/Norton MA
153 PM EDT Sun Sep 13 2026

MAC005-023-131803-
/O.EXP.KBOX.FF.W.0013.000000T0000Z-260913T1800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Bristol MA-Plymouth MA-
153 PM EDT Sun Sep 13 2026

...FLASH FLOOD WARNING WILL EXPIRE AT 2 PM EDT THIS AFTERNOON FOR
SOUTHEASTERN BRISTOL AND SOUTH CENTRAL PLYMOUTH COUNTIES...

While the heaviest rain has come to an end, areas of additional
localized flooding and ponding are possible over the next several
hours. Please continue to heed remaining road closures.

A Flood Watch remains in effect until 600 PM EDT for portions of
southeastern Massachusetts and Rhode Island.

&&

LAT...LON 4177 7103 4151 7101 4158 7081 4177 7069
      4178 7079

$$

FT

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 13, 10:46 AM EDTFlash Flood WarningBOXBristol3 hr
Sep 13, 2:23 PM EDTSmall Craft AdvisoryBOX26 hr

Nearby

Flash Flood Warnings in Massachusetts, 2026Every flash flood warning in 2026

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.