Alert archive / Connecticut / Flash Flood Warnings in 2020

Flash Flood Warning 21, NWS New York, NY

July 23, 2020Greater Bridgeport Planning Region, Naugatuck Valley Planning Region, Connecticut

NWS New York, NY issued this flash flood warning at Jul 23, 2020, 9:53 PM EDT for Greater Bridgeport Planning Region, Naugatuck Valley Planning Region, Connecticut. It was in force for 116 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 23, 2020, 9:53 PM EDT (01:53 UTC)
Expired
Jul 23, 2020, 11:49 PM EDT
In force
116 min
Issued by
NWS New York, NY
Area
Storm-based polygon
Flood severity
None

Counties Greater Bridgeport Planning Region, CT, Naugatuck Valley Planning Region, CT

The radar

The Brookhaven radar (KOKX), 60 km from the middle of the area, began a volume at 01:56 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.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 00:00Z, 1.9 hours before the alert went out and 60 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 2020-07-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1702 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 2020-07-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 111 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
1702 J/kg
Mixed-layer CIN
-49 J/kg
Mixed-layer LCL
797 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
111 m²/s²
0-3 km storm-relative helicity
116 m²/s²
Significant tornado parameter
0.6
Supercell composite
4.0

Open this sounding in Storm Lab

The text

As transmitted.

677 
WGUS51 KOKX 240153
FFWOKX
CTC001-009-240445-
/O.NEW.KOKX.FF.W.0021.200724T0153Z-200724T0445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service New York NY
953 PM EDT Thu Jul 23 2020

The National Weather Service in Upton NY has issued a

* Flash Flood Warning for...
  Central Fairfield County in southern Connecticut...
  Southwestern New Haven County in southern Connecticut...

* Until 1245 AM EDT.

* At 952 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Radar has indicated between 1 
  and 2 inches of rain have fallen. Flash flooding is ongoing or 
  expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar indicated.

  IMPACT...Flooding of small creeks and streams, urban areas, 
           highways, streets and underpasses as well as other 
           drainage and low lying areas.

* Some locations that will experience flooding include...
  Bridgeport, New Haven, Danbury, Milford, Shelton, Southbury,
  Newtown, Fairfield, Hamden, Stratford, Trumbull, Ridgefield,
  Monroe, Bethel and Wilton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.

&&

LAT...LON 4142 7290 4122 7301 4121 7306 4123 7335
      4125 7351 4130 7355 4140 7354 4144 7339

FLASH FLOOD...RADAR INDICATED

$$

JM
1 follow-up statement
115 
WGUS71 KOKX 240349
FFSOKX

Flash Flood Statement
National Weather Service New York NY
1149 PM EDT Thu Jul 23 2020

CTC001-009-240359-
/O.CAN.KOKX.FF.W.0021.000000T0000Z-200724T0445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Fairfield CT-New Haven CT-
1149 PM EDT Thu Jul 23 2020

...THE FLASH FLOOD WARNING FOR CENTRAL FAIRFIELD AND SOUTHWESTERN NEW
HAVEN COUNTIES IS CANCELLED...

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

LAT...LON 4142 7290 4122 7301 4121 7306 4123 7335
      4125 7351 4130 7355 4140 7354 4144 7339

$$

JM

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 23, 8:14 PM EDTSpecial Weather StatementOKX46 min
Jul 23, 8:39 PM EDTSpecial Weather StatementOKX36 min
Jul 23, 9:04 PM EDTSevere Thunderstorm WarningOKXLower Connecticut River Valley Planning Region, Naugatuck Valley Planning Region28 min
Jul 23, 9:07 PM EDTSevere Thunderstorm WarningOKXGreater Bridgeport Planning Region, Naugatuck Valley Planning Region38 min
Jul 23, 9:19 PM EDTAreal Flood AdvisoryOKXGreater Bridgeport Planning Region, Naugatuck Valley Planning Region3 hr
Jul 23, 9:37 PM EDTSpecial Weather StatementOKX53 min
Jul 23, 9:43 PM EDTSevere Thunderstorm WarningOKXGreater Bridgeport Planning Region, Naugatuck Valley Planning Region62 min

Nearby

Flash Flood Warnings in Connecticut, 2020Every flash flood warning in 2020

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.