Alert archive / Rhode Island / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 80, NWS Boston/Norton, MA

July 17, 2021Kent County, Providence County, Rhode Island; Northeastern Connecticut Planning Region, Connecticut

NWS Boston/Norton, MA issued this severe thunderstorm warning at Jul 17, 2021, 4:29 PM EDT for Kent County, Providence County, Rhode Island; Northeastern Connecticut Planning Region, Connecticut. It was in force for 61 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 17, 2021, 4:29 PM EDT (20:29 UTC)
Expired
Jul 17, 2021, 5:30 PM EDT
In force
61 min
Issued by
NWS Boston/Norton, MA
Area
Storm-based polygon
Tornado
Possible
Hail
1.0 in
Wind
60.0 mph

Counties Northeastern Connecticut Planning Region, CT, Kent County, RI, Providence County, RI

The radar

The Boston radar (KBOX), 51 km from the middle of the area, began a volume at 20:29 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 12:00Z, 8.5 hours before the alert went out and 143 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 2021-07-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1203 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 2021-07-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 35 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
1203 J/kg
Mixed-layer CIN
-55 J/kg
Mixed-layer LCL
1054 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
35 m²/s²
0-3 km storm-relative helicity
46 m²/s²
Significant tornado parameter
0.2
Supercell composite
1.0

Open this sounding in Storm Lab

The text

As transmitted.

750 
WUUS51 KBOX 172029
SVRBOX
CTC015-RIC003-007-172130-
/O.NEW.KBOX.SV.W.0080.210717T2029Z-210717T2130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Boston/Norton MA
429 PM EDT Sat Jul 17 2021

The National Weather Service in Boston/Norton has issued a

* Severe Thunderstorm Warning for...
  East central Windham County in northern Connecticut...
  Central Kent County in Rhode Island...
  Southwestern Providence County in Rhode Island...

* Until 530 PM EDT.

* At 429 PM EDT, a severe thunderstorm was located over Killingly, or
  9 miles north of Plainfield, moving east at 10 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Expect wind damage to trees and power lines. Minor hail 
           damage to vehicles is possible.

* Locations impacted include...
  Cranston, Coventry, North Providence, West Warwick, Johnston,
  Smithfield, Lincoln, Killingly, Burrillville, Scituate, Glocester,
  Putnam, Thompson and Foster.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4181 7190 4194 7185 4192 7147 4166 7152
TIME...MOT...LOC 2029Z 278DEG 9KT 4183 7183 

TORNADO...POSSIBLE
HAIL...1.00IN
WIND...60MPH
 
$$

BL
1 follow-up statement
302 
WWUS51 KBOX 172102
SVSBOX

Severe Weather Statement
National Weather Service Boston/Norton MA
502 PM EDT Sat Jul 17 2021

CTC015-RIC003-007-172130-
/O.CON.KBOX.SV.W.0080.000000T0000Z-210717T2130Z/
Windham CT-Kent RI-Providence RI-
502 PM EDT Sat Jul 17 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 530 PM EDT
FOR EAST CENTRAL WINDHAM...CENTRAL KENT AND SOUTHWESTERN PROVIDENCE
COUNTIES...

At 502 PM EDT, a severe thunderstorm was located over Scituate, or
near Johnston, moving east at 20 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Expect wind damage to trees and power lines. Minor hail 
         damage to vehicles is possible.

Locations impacted include...
Cranston, Coventry, North Providence, West Warwick, Johnston,
Smithfield, Lincoln, Killingly, Scituate, Glocester, Putnam and
Foster.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4181 7181 4193 7182 4192 7147 4166 7152
TIME...MOT...LOC 2102Z 277DEG 18KT 4182 7165 

HAIL...1.00IN
WIND...60MPH
 
$$

BL

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 17, 2:14 PM EDTSpecial Weather StatementBOXBristol46 min
Jul 17, 2:39 PM EDTAreal Flood WarningBOXKent, Providence111 min
Jul 17, 2:46 PM EDTSpecial Weather StatementBOXProvidence44 min
Jul 17, 2:53 PM EDTSevere Thunderstorm WarningBOXProvidence52 min
Jul 17, 3:26 PM EDTSevere Thunderstorm WarningBOXProvidence64 min
Jul 17, 3:36 PM EDTAreal Flood WarningBOXKent, Providence114 min
Jul 17, 4:06 PM EDTFlash Flood WarningBOXKent, Providence4 hr
Jul 17, 5:30 PM EDTFlash Flood WarningBOXProvidence3 hr
Jul 17, 5:49 PM EDTSpecial Weather StatementBOXBristol41 min
Jul 17, 6:05 PM EDTSevere Thunderstorm WarningBOXBristol, Kent, Providence26 min
Jul 17, 1:59 PM EDTSpecial Weather StatementBOX46 min
Jul 17, 3:47 PM EDTAreal Flood WarningBOXNortheastern Connecticut Planning Region118 min
Jul 17, 4:14 PM EDTFlash Flood WarningBOXNortheastern Connecticut Planning Region5 hr
Jul 17, 4:15 PM EDTSevere Thunderstorm WarningBOXNortheastern Connecticut Planning Region60 min
Jul 17, 4:18 PM EDTSevere Thunderstorm WarningBOXNortheastern Connecticut Planning Region57 min
Jul 17, 4:20 PM EDTSpecial Weather StatementBOX40 min
Jul 17, 4:38 PM EDTSevere Thunderstorm WarningBOXCapitol Planning Region67 min
Jul 17, 4:58 PM EDTFlash Flood WarningBOXCapitol Planning Region2 hr
Jul 17, 5:21 PM EDTFlash Flood WarningBOXCapitol Planning Region, Northeastern Connecticut Planning Region5 hr

Nearby

Severe Thunderstorm Warnings in Rhode Island, 2021Severe Thunderstorm Warnings in Connecticut, 2021Every severe thunderstorm 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.