Alert archive / Connecticut / Areal Flood Warnings in 2021

Areal Flood Warning 13, NWS Boston/Norton, MA

July 17, 2021Northeastern Connecticut Planning Region, Connecticut

NWS Boston/Norton, MA issued this areal flood warning at Jul 17, 2021, 10:09 PM EDT for Northeastern Connecticut Planning Region, Connecticut. It was in force for 6 hr. 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 17, 2021, 10:09 PM EDT (02:09 UTC)
Expired
Jul 18, 2021, 4:03 AM EDT
In force
6 hr
Issued by
NWS Boston/Norton, MA
Area
Storm-based polygon
Flood severity
None

County Northeastern Connecticut Planning Region, CT

The radar

The Boston radar (KBOX), 86 km from the middle of the area, began a volume at 02:12 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, 2.2 hours before the alert went out and 127 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 2021-07-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1431 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 2021-07-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 26 square meters per square second.1939Sfc1 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
1431 J/kg
Mixed-layer CIN
-48 J/kg
Mixed-layer LCL
988 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
26 m²/s²
0-3 km storm-relative helicity
54 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.6

Open this sounding in Storm Lab

The text

As transmitted.

876 
WGUS41 KBOX 180209
FLWBOX

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Flood Warning
National Weather Service Boston/Norton MA
1009 PM EDT Sat Jul 17 2021

CTC013-015-180500-
/O.NEW.KBOX.FA.W.0013.210718T0209Z-210718T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Tolland CT-Windham CT-
1009 PM EDT Sat Jul 17 2021

The National Weather Service in Norton has issued a

* Flood Warning for Small stream in...
  Eastern Tolland County in northern Connecticut...
  West Central Windham County in northern Connecticut...

* Until 100 AM EDT.

* At 1009 PM EDT, Flooding is already occurring in the warned area. 
  Doppler radar indicated between 3 and 5 inches of rain have fallen.

* The local fire department reported that as of 820 PM Route 44 was 
  closed between Route 74 and one half mile west of Route 89. In 
  addition, Route 74 remains closed between Route 44 and Krapf Road.

* Some locations that will experience flooding include...
  Mansfield, Ashford and Chaplin.

The Mount Hope River at Warrenville crested at 10.7 feet at 745 PM. 
As of 945 PM the Mount Hope River at Warrenville was at 9.7 feet and 
falling, but is still in Moderate Flood Stage.

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.

&&

LAT...LON 4193 7218 4193 7217 4187 7215 4181 7216
      4181 7218 4187 7217

$$

BL
2 follow-up statements
235 
WGUS81 KBOX 180549
FLSBOX

Flood Statement
National Weather Service Boston/Norton MA
149 AM EDT Sun Jul 18 2021

CTC013-015-180900-
/O.CON.KBOX.FA.W.0013.000000T0000Z-210718T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Tolland CT-Windham CT-
149 AM EDT Sun Jul 18 2021

...THE SMALL STREAM FLOOD WARNING REMAINS IN EFFECT UNTIL 5 AM EDT 
EARLY THIS MORNING FOR EASTERN TOLLAND AND WEST CENTRAL WINDHAM 
COUNTIES...

At 149 AM EDT, Doppler radar and automated rain gauges indicated 
slow moving thunderstorms with very heavy rainfall across the warned 
area. Between 3 and 5 inches of rain have fallen.

Some locations that will experience flooding include...
  Mansfield, Ashford and Chaplin.

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.

&&

LAT...LON 4193 7218 4193 7217 4187 7215 4181 7216
      4181 7218 4187 7217

$$

Belk
884 
WGUS81 KBOX 180803
FLSBOX

Flood Statement
National Weather Service Boston/Norton MA
403 AM EDT Sun Jul 18 2021

CTC013-015-180813-
/O.CAN.KBOX.FA.W.0013.000000T0000Z-210718T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Tolland CT-Windham CT-
403 AM EDT Sun Jul 18 2021

...THE SMALL STREAM FLOOD WARNING IS CANCELLED FOR EASTERN TOLLAND 
AND WEST CENTRAL WINDHAM COUNTIES...

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

LAT...LON 4193 7218 4193 7217 4187 7215 4181 7216
      4181 7218 4187 7217

$$

Belk

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 17, 9:54 PM EDTSpecial Weather StatementBOX51 min
Jul 18, 1:39 AM EDTAreal Flood WarningBOXCapitol Planning Region2 hr
Jul 18, 1:53 AM EDTSpecial Weather StatementBOX67 min
Jul 18, 2:22 AM EDTSpecial Weather StatementBOX53 min
Jul 18, 2:48 AM EDTAreal Flood WarningBOXCapitol Planning Region, Northeastern Connecticut Planning Region105 min
Jul 18, 6:22 AM EDTAreal Flood WarningBOXNortheastern Connecticut Planning Region5 hr
Jul 18, 9:33 AM EDTAreal Flood WarningBOXCapitol Planning Region5 hr
Jul 18, 12:19 PM EDTAreal Flood WarningBOXNortheastern Connecticut Planning Region21 hr
Jul 18, 1:40 PM EDTAreal Flood WarningBOXNortheastern Connecticut Planning Region6 hr

Nearby

Areal Flood Warnings in Connecticut, 2021Every areal 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.