Alert archive / Massachusetts / Flash Flood Warnings in 2025
Flash Flood Warning 9, NWS Boston/Norton, MA
NWS Boston/Norton, MA issued this flash flood warning at Jul 10, 2025, 8:15 AM EDT for Norfolk County, Plymouth County, Suffolk County, Massachusetts. It was in force for 3 hr. 7 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 10, 2025, 8:15 AM EDT (12:15 UTC)
- Expired
- Jul 10, 2025, 11:15 AM EDT
- In force
- 3 hr
- Issued by
- NWS Boston/Norton, MA
- Area
- Storm-based polygon
- Damage threat
- Considerable
- Flood severity
- None
Counties Norfolk County, MA, Plymouth County, MA, Suffolk County, MA
The radar
The Boston radar (KBOX), 37 km from the middle of the area, began a volume at 12:15 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
| Time | Report | Where | Remark |
|---|---|---|---|
| Jul 10, 8:45 AM EDT | FLASH FLOOD | 1 Ene Hingham, MA | In Hingham, portions of East St (Route 228) and Hersey St were flooded. Report relayed by Amateur Radio. |
| Jul 10, 8:45 AM EDT | FLASH FLOOD | 1 Ene Hingham, MA | In Hingham, portions of East St (Route 228) and Hersey St were flooded. Report relayed by Amateur Radio. |
| Jul 10, 8:45 AM EDT | FLASH FLOOD | 1 N Braintree, MA | MBTA reported Red Line T service suspended between Quincy Adams and Braintree due to flooding at Braintree. |
| Jul 10, 8:45 AM EDT | FLASH FLOOD | 1 N Braintree, MA | MBTA reported Red Line T service suspended between Quincy Adams and Braintree due to flooding at Braintree. |
| Jul 10, 8:47 AM EDT | FLASH FLOOD | 1 S Weymouth, MA | In Weymouth, a car was stranded due to flooding at the intersection of Prince St and Lake St. The Weymouth Landing area was closed due to flooding. |
| Jul 10, 8:47 AM EDT | FLASH FLOOD | 1 S Weymouth, MA | In Weymouth, a car was stranded due to flooding at the intersection of Prince St and Lake St. The Weymouth Landing area was closed due to flooding. |
| Jul 10, 9:30 AM EDT | FLASH FLOOD | 2 Wnw Cohasset, MA | In Cohasset, Route 3A at Lower King St was closed due to flooding. |
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, 0.3 hours before the alert went out and 222 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.
- Mixed-layer CAPE
- 78 J/kg
- Mixed-layer CIN
- -47 J/kg
- Mixed-layer LCL
- 735 m above ground
- 0-6 km bulk shear
- 33 kt
- 0-1 km storm-relative helicity
- 39 m²/s²
- 0-3 km storm-relative helicity
- 65 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.5
The text
As transmitted.
092
WGUS51 KBOX 101215
FFWBOX
MAC021-023-025-101515-
/O.NEW.KBOX.FF.W.0009.250710T1215Z-250710T1515Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Boston/Norton MA
815 AM EDT Thu Jul 10 2025
The National Weather Service in Norton has issued a
* Flash Flood Warning for...
Northeastern Norfolk County in eastern Massachusetts...
Southern Suffolk County in eastern Massachusetts...
North Central Plymouth County in southeastern Massachusetts...
* Until 1115 AM EDT.
* At 815 AM EDT, the public reported thunderstorms producing heavy
rain across the warned area. Between 2 and 4 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 already occurring.
HAZARD...Life threatening flash flooding. Thunderstorms
producing flash flooding.
SOURCE...Public reported.
IMPACT...Life threatening flash flooding of creeks and streams,
urban areas, highways, streets and underpasses.
* Some locations that will experience flash flooding include...
Boston, Quincy, Weymouth, Braintree, Randolph, Milton, Stoughton,
Dedham, Hingham, Canton, Scituate, Winthrop, Holbrook, Hull,
Cohasset and Avon.
Several roads closed in the warning area including I-93 near Furnace
Brook Parkway.
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.
Stay away or be swept away. River banks and culverts can become
unstable and unsafe.
&&
LAT...LON 4225 7076 4215 7106 4226 7118 4238 7098
FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
EXPECTED RAINFALL RATE...1-2 INCHES IN 1 HOUR
$$
RM1 follow-up statement
494
WGUS71 KBOX 101339
FFSBOX
Flash Flood Statement
National Weather Service Boston/Norton MA
939 AM EDT Thu Jul 10 2025
MAC021-023-025-101515-
/O.CON.KBOX.FF.W.0009.000000T0000Z-250710T1515Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Norfolk MA-Plymouth MA-Suffolk MA-
939 AM EDT Thu Jul 10 2025
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1115 AM EDT THIS
MORNING FOR NORTHEASTERN NORFOLK, SOUTHERN SUFFOLK AND NORTH CENTRAL
PLYMOUTH COUNTIES...
At 939 AM EDT, The heaviest rainfall associated with this warning
has past, but many roads remain flooded. It will take time for flood
waters to recede, thus the warning remains in effect.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Public reported.
IMPACT...Flash flooding of small creeks and streams, urban areas,
highways, streets and underpasses as well as other poor
drainage and low-lying areas.
Some locations that will experience flash flooding include...
Boston, Quincy, Weymouth, Braintree, Randolph, Milton, Stoughton,
Dedham, Hingham, Canton, Scituate, Winthrop, Holbrook, Hull,
Cohasset and Avon.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Be aware of your surroundings and do not drive on flooded roads.
&&
LAT...LON 4225 7076 4215 7106 4226 7118 4238 7098
FLASH FLOOD...OBSERVED
EXPECTED RAINFALL RATE...1-2 INCHES IN 1 HOUR
$$
RMThe office that day
Everything else NWS Boston/Norton, MA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 10, 2:10 AM EDT | Flood Watch | BOX | Bristol, Essex, Middlesex, Norfolk, Plymouth, Suffolk and 1 more | 8 hr |
| Jul 10, 2:43 AM EDT | Special Marine Warning | BOX | 62 min | |
| Jul 10, 6:01 AM EDT | Flash Flood Warning | BOX | Bristol, Middlesex, Norfolk, Plymouth, Suffolk, Worcester | 3 hr |
Nearby
Flash Flood Warnings in Massachusetts, 2025Every flash flood warning in 2025
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.