Alert archive / Vermont / Flash Flood Warnings in 2023

Flash Flood Warning 46, NWS Burlington, VT

July 21, 2023Addison County, Vermont

NWS Burlington, VT issued this flash flood warning at Jul 21, 2023, 2:52 PM EDT for Addison County, Vermont. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jul 21, 2023, 2:52 PM EDT (18:52 UTC)
Expired: Jul 21, 2023, 5:45 PM EDT
In force: 3 hr
Issued by: NWS Burlington, VT
Area: Storm-based polygon
Flood severity: None

County Addison County, VT

The radar

The Burlington radar (KCXX), 53 km from the middle of the area, began a volume at 18:55 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

Gray, ME (KGYX), launched 12:00Z, 6.9 hours before the alert went out and 231 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1098 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 58 m²/s²
0-3 km storm-relative helicity: 85 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Burlington, VT wrote its last area forecast discussion before this flash flood warning went out at Jul 21, 1:45 PM EDT, 1 hour 7 minutes earlier.

Area forecast discussion, Jul 21, 1:45 PM EDT, 1 hour 7 minutes before

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Hazardous weather outlook, Jul 21, 3:35 AM EDT, 11 hours 17 minutes before

Hazardous Weather Outlook
National Weather Service Burlington VT
335 AM EDT Fri Jul 21 2023

NYZ026>031-034-035-087-VTZ001>011-016>021-220745-
Northern St. Lawrence-Northern Franklin-Eastern Clinton-
Southeastern St. Lawrence-Southern Franklin-Western Clinton-
Western Essex-Eastern Essex-Southwestern St. Lawrence-Grand Isle-
Western Franklin-Orleans-Essex-Western Chittenden-Lamoille-Caledonia-
Washington-Western Addison-Orange-Western Rutland-Eastern Franklin-
Eastern Chittenden-Eastern Addison-Eastern Rutland-Western Windsor-
Eastern Windsor-
335 AM EDT Fri Jul 21 2023

...FLOOD WATCH IN EFFECT FROM NOON EDT TODAY THROUGH LATE TONIGHT...

This Hazardous Weather Outlook is for northern New York, central
Vermont, northeast Vermont, northwest Vermont and southern Vermont.

.DAY ONE...Today and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Flood Watch.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

Hazardous weather is not expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

In the hours before

Special weather statement, Jul 21, 11:53 AM EDT, 2 hours 59 minutes before

Special Weather Statement
National Weather Service Burlington VT
1153 AM EDT Fri Jul 21 2023

NYZ029-087-211700-
Southeastern St. Lawrence NY-Southwestern St. Lawrence NY-
1153 AM EDT Fri Jul 21 2023

...Strong thunderstorms will impact portions of central St. Lawrence
County through 100 PM EDT...

At 1152 AM EDT, Doppler radar was tracking strong thunderstorms along
a line extending from Heuvelton to near Edwardsville to near Redwood.
Movement was east at 20 mph.

HAZARD...Winds in excess of 40 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Potsdam, Gouverneur, Canton, De Kalb, Fowler, Colton, Rensselaer
Falls, Morley, Hermon, Heuvelton, Richville, Madrid, Pierrepont,
Russell, De Peyster, Rossie, Edwards, West Parishville, Talcville,
and West Stockholm.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with these storms and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 4444 7562 4470 7543 4472 7478 4453 7495
      4425 7531 4424 7551 4435 7574
TIME...MOT...LOC 1552Z 258DEG 17KT 4462 7541 4445 7554 4430 7575

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

Banacos

Special weather statement, Jul 21, 1:04 PM EDT, 1 hour 48 minutes before

Special Weather Statement
National Weather Service Burlington VT
104 PM EDT Fri Jul 21 2023

NYZ029-087-211800-
Southeastern St. Lawrence NY-Southwestern St. Lawrence NY-
104 PM EDT Fri Jul 21 2023

...A strong thunderstorm will impact portions of southwestern St.
Lawrence County through 200 PM EDT...

At 103 PM EDT, Doppler radar was tracking a strong thunderstorm over
Gouverneur, moving east at 30 mph.

HAZARD...Winds in excess of 40 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Gouverneur, De Kalb, Fowler, Colton, Degrasse, Richville, Hermon,
Pierrepont, Russell, Rossie, Edwards, Pyrites, Talcville, South
Edwards, Nelson Corner, North Russell, Fullerville, De Kalb Junction,
North Gouverneur, and Balmat.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

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

&&

LAT...LON 4445 7566 4456 7494 4426 7496 4423 7548
      4436 7576
TIME...MOT...LOC 1703Z 261DEG 25KT 4435 7552

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

Banacos

Special weather statement, Jul 21, 2:00 PM EDT, 52 minutes before

Special Weather Statement
National Weather Service Burlington VT
200 PM EDT Fri Jul 21 2023

NYZ029-087-211900-
Southeastern St. Lawrence NY-Southwestern St. Lawrence NY-
200 PM EDT Fri Jul 21 2023

...A strong thunderstorm will impact portions of southern St.
Lawrence County through 300 PM EDT...

At 159 PM EDT, Doppler radar was tracking a strong thunderstorm near
Degrasse, moving east at 15 mph.

HAZARD...Winds in excess of 40 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Gouverneur, Oswegatchie, Fowler, Degrasse, Cranberry Lake, Fine,
Pitcairn, Stark, Edwards, Lower Oswegatchie, Talcville, South
Edwards, Fullerville, Newton Falls, Balmat, Shurtleff, West Fowler,
and South Russell.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

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

&&

LAT...LON 4438 7531 4446 7475 4420 7471 4416 7532
      4430 7564
TIME...MOT...LOC 1759Z 264DEG 14KT 4431 7515

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

Banacos

Special weather statement, Jul 21, 2:14 PM EDT, 38 minutes before

Special Weather Statement
National Weather Service Burlington VT
214 PM EDT Fri Jul 21 2023

VTZ008-009-018-211915-
Washington VT-Western Addison VT-Eastern Addison VT-
214 PM EDT Fri Jul 21 2023

...A strong thunderstorm will impact portions of central Addison and
southwestern Washington Counties through 315 PM EDT...

At 214 PM EDT, Doppler radar was tracking a strong thunderstorm over
Cornwall, moving northeast at 10 mph.

HAZARD...Wind gusts up to 50 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Middlebury, Cornwall, Weybridge, Salisbury, Ripton, Bristol, Lincoln,
Whiting, New Haven, Bridport, Granville, Starksboro, Shoreham,
Waltham, Addison, Hancock, Monkton, East Middlebury, West Lincoln,
and Lake Dunmore.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

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

&&

LAT...LON 4385 7325 4401 7339 4422 7303 4399 7284
TIME...MOT...LOC 1814Z 238DEG 10KT 4400 7321

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...50 MPH

Banacos

The office that day

Everything else NWS Burlington, VT issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 21, 4:56 AM EDT	Flash Flood Warning	BTV	Addison, Chittenden	2 hr
Jul 21, 6:59 AM EDT	Areal Flood Warning	BTV	Addison, Chittenden	61 min
Jul 21, 2:14 PM EDT	Special Weather Statement	BTV	Addison	61 min
Jul 21, 3:26 PM EDT	Severe Thunderstorm Warning	BTV	Franklin, Grand Isle	64 min
Jul 21, 3:33 PM EDT	Special Weather Statement	BTV	Washington	57 min
Jul 21, 3:44 PM EDT	Severe Thunderstorm Warning	BTV	Addison, Orange, Washington	38 min
Jul 21, 4:29 PM EDT	Severe Thunderstorm Warning	BTV	Franklin, Grand Isle	61 min
Jul 21, 4:33 PM EDT	Severe Thunderstorm Warning	BTV	Addison, Orange, Rutland, Washington, Windsor	57 min
Jul 21, 4:50 PM EDT	Special Weather Statement	BTV	Franklin, Grand Isle	25 min
Jul 21, 5:04 PM EDT	Severe Thunderstorm Warning	BTV	Chittenden, Franklin, Grand Isle, Lamoille	56 min
Jul 21, 5:09 PM EDT	Areal Flood Warning	BTV	Rutland, Windsor	3 hr
Jul 21, 5:39 PM EDT	Severe Thunderstorm Warning	BTV	Chittenden	66 min
Jul 21, 5:49 PM EDT	Areal Flood Warning	BTV	Franklin	13 min
Jul 21, 5:53 PM EDT	Special Weather Statement	BTV	Addison	67 min
Jul 21, 6:02 PM EDT	Flash Flood Warning	BTV	Franklin	3 hr
Jul 21, 6:14 PM EDT	Special Weather Statement	BTV	Rutland	61 min
Jul 21, 6:39 PM EDT	Special Weather Statement	BTV	Chittenden	66 min
Jul 21, 7:55 PM EDT	Special Weather Statement	BTV	Essex, Orleans	65 min
Jul 21, 11:53 AM EDT	Special Weather Statement	BTV	St. Lawrence	67 min
Jul 21, 1:04 PM EDT	Special Weather Statement	BTV	St. Lawrence	56 min
Jul 21, 1:16 PM EDT	Areal Flood Warning	BTV	St. Lawrence	3 hr
Jul 21, 2:00 PM EDT	Special Weather Statement	BTV	St. Lawrence	60 min

Nearby

Flash Flood Warnings in Vermont, 2023 Every flash flood warning in 2023

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.