Alert archive / Connecticut / Flash Flood Warnings in 2025

Flash Flood Warning 21, NWS New York, NY

August 13, 2025Naugatuck Valley Planning Region, Connecticut

NWS New York, NY issued this flash flood warning at Aug 13, 2025, 3:21 PM EDT for Naugatuck Valley Planning Region, Connecticut. It was in force for 112 min. 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: Aug 13, 2025, 3:21 PM EDT (19:21 UTC)
Expired: Aug 13, 2025, 5:13 PM EDT
In force: 112 min
Issued by: NWS New York, NY
Area: Storm-based polygon
Flood severity: None

County Naugatuck Valley Planning Region, CT

The radar

The Brookhaven radar (KOKX), 74 km from the middle of the area, began a volume at 19:25 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
Aug 13, 4:06 PM EDT	FLASH FLOOD	1 S Middlebury, CT	6 inches of running water across I-84 Westbound in Middlebury.

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, 7.4 hours before the alert went out and 74 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1273 J/kg
Mixed-layer CIN: -45 J/kg
Mixed-layer LCL: 892 m above ground
0-6 km bulk shear: 19 kt
0-1 km storm-relative helicity: 44 m²/s²
0-3 km storm-relative helicity: 60 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.9

Open this sounding in Storm Lab

The text

As transmitted.

892 
WGUS51 KOKX 131921
FFWOKX
CTC009-132200-
/O.NEW.KOKX.FF.W.0021.250813T1921Z-250813T2200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service New York NY
321 PM EDT Wed Aug 13 2025

The National Weather Service in Upton has issued a

* Flash Flood Warning for...
  Northwestern New Haven County in southern Connecticut...

* Until 600 PM EDT.

* At 321 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 3.5 inches of 
  rain have fallen. The expected rainfall rate is 1 inch 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...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...
  Waterbury, Naugatuck, Southbury, Prospect, Middlebury, Beacon 
  Falls, Bethany and Oxford.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Move to higher ground now. Act quickly to protect your life.

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 4154 7310 4153 7298 4143 7302 4149 7316
      4151 7317 4151 7316 4152 7316

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

$$

MET

2 follow-up statements

366 
WGUS71 KOKX 132025
FFSOKX

Flash Flood Statement
National Weather Service New York NY
425 PM EDT Wed Aug 13 2025

CTC009-132200-
/O.CON.KOKX.FF.W.0021.000000T0000Z-250813T2200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Haven CT-
425 PM EDT Wed Aug 13 2025

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 6 PM EDT THIS EVENING 
FOR NORTHWESTERN NEW HAVEN COUNTY...

At 425 PM EDT, Doppler radar indicated that the thunderstorms that 
produced heavy rain across the warned area have dissipated. However, 
between 3 and 5 inches of rain have fallen. Flooding impacts will 
continue, but no additional rainfall is expected. 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...
  Waterbury, Naugatuck, Southbury, Prospect, Middlebury, Beacon 
  Falls, Bethany and Oxford.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Move to higher ground now. Act quickly to protect your life.

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 4151 7317 4151 7316 4152 7316 4154 7310
      4153 7298 4143 7302 4149 7316

FLASH FLOOD...RADAR INDICATED

$$

MET

070 
WGUS71 KOKX 132113
FFSOKX

Flash Flood Statement
National Weather Service New York NY
513 PM EDT Wed Aug 13 2025

CTC009-132123-
/O.CAN.KOKX.FF.W.0021.000000T0000Z-250813T2200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Haven CT-
513 PM EDT Wed Aug 13 2025

...FLASH FLOOD WARNING IS CANCELLED FOR NORTHWESTERN NEW HAVEN 
COUNTY...

Flood waters have receded. The heavy rain has ended. Flooding is no 
longer expected to pose a threat. Please continue to heed remaining 
road closures.

&&

LAT...LON 4151 7317 4151 7316 4152 7316 4154 7310
      4153 7298 4143 7302 4149 7316

$$

MET

The office that day

Everything else NWS New York, NY issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 13, 2:32 PM EDT	Special Weather Statement	OKX		43 min
Aug 13, 2:52 PM EDT	Special Weather Statement	OKX		38 min
Aug 13, 3:01 PM EDT	Areal Flood Advisory	OKX	Naugatuck Valley Planning Region	20 min
Aug 13, 3:33 PM EDT	Special Weather Statement	OKX		42 min
Aug 13, 6:54 PM EDT	Areal Flood Advisory	OKX	Greater Bridgeport Planning Region	54 min

Nearby

Flash Flood Warnings in Connecticut, 2025 Every 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.