An upper level disturbance and strong cold front moved into a warm, moist unstable airmass across northern NY and VT during the afternoon of June 21st. Thunderstorms developed ahead of this cold front, with strong winds aloft, to help support locally severe storms with damaging winds across VT.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS BTV wrote it up.
An upper level disturbance and strong cold front moved into a warm, moist unstable airmass across northern NY and VT during the afternoon of June 21st. Thunderstorms developed ahead of this cold front, with strong winds aloft, to help support locally severe storms with damaging winds across VT.
The local office's own words before the first event, 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 the first event at Jun 21, 2:27 PM EST, 26 minutes earlier.
Area Forecast Discussion National Weather Service Burlington VT 327 PM EDT Mon Jun 21 2021 .SYNOPSIS... Thunderstorms, some strong to severe, will continue to move across the North Country this afternoon and evening. Damaging winds, large hail, heavy downpours, and frequent lightning will be the main threats with any thunderstorms. The threat for storms will come to an end later tonight as a cold front moves into the region and cooler and drier weather moves in for the remainder of the week. && .NEAR TERM /THROUGH TUESDAY NIGHT/... As of 327 PM EDT Monday...Forecast remains on track for strong to severe thunderstorms this afternoon and evening across much of our area. Main area of thunderstorms is moving into the northern Adirondacks and we have already had reports of downed trees across portions of Saint Lawrence County. Deep layer shear remains favorable over the area and storms are moving into area of maximum instability. Thus expect strong to severe storms to continue this afternoon and evening over the remainder of our area with damaging winds, large hail, heavy downpours, and frequent lightning. Eventually the convection comes to an end later tonight as a cold front moves in overnight. Cooler and drier air will help decrease the areal coverage of showers with a few lingering showers later on Tuesday over southern Vermont. Noticeable cooler temperatures will be on tap for Tuesday with highs in the 60s to around 70. Dry weather and no precipitation is expected Tuesday night with lows in the 40s, but some 30s in the mountains. && .SHORT TERM /WEDNESDAY THROUGH FRIDAY/... As of 327 PM EDT Monday...A quiet stretch of weather is expected for the middle to end of the work week as a ridge of high pressure builds into the region. On Wednesday temperatures will run several degrees below normal as a cold upper level trough traverses the area. Highs will be cool in the upper 60s to low 70s, and lows Wednesday night in the mid 40s to low 50s under clear/sunny skies. As the surface high shifts offshore Thursday, more summer-like temperatures evolve as south/southwesterly surface to mid-level flow redevelops. Highs both days bump back into the upper 70s to mid 80s, with lows near normal to slightly above in the 50s to 60s. && .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... As of 327 PM EDT Monday...Heading into the weekend attention turns to a developing full-latitude trough over the central CONUS which will enhance southwesterly flow over the Northeast and usher in increased heat and humidity. Temperatures each day will be firmly in the upper 70s to mid 80s with dewpoints increasingly muggy, especially Sunday and Monday. The potential for afternoon/evening showers and thunderstorms will also exist each day with the best chances Sunday and Monday. && .AVIATION /19Z MONDAY THROUGH SATURDAY/... Through 18Z Tuesday...Heads up for strong to severe thunderstorms across the entire area right through 02z. Wind gusts of 40 to 50 knots can be expected with any of the storms along with heavy rainfall and frequent lightning. There may even be some hail as well. These storms will produce IFR to LIFR conditions during this period. Improving conditions are expected between 02z and 06z as storms come to an end, but showers linger. Eventually the winds shift to the west and northwest after 12z and VFR conditions are then expected for the remainder of the period. Outlook... Tuesday Night: VFR. NO SIG WX. Wednesday: VFR. NO SIG WX. Wednesday Night: VFR. NO SIG WX. Thursday: VFR. NO SIG WX. Thursday Night: VFR. NO SIG WX. Friday: VFR. NO SIG WX. Friday Night: VFR. Chance SHRA. Saturday: VFR. Chance SHRA, Slight chance TSRA. && .MARINE... Active weather will continue into tonight across Lake Champlain with south winds in the 15 to 25 knot range with gusts to 35 knots. This will create very choppy conditions, especially over the northern portions of the lake. Storms will move across the lake through 7:00 pm and any storms will likely produce strong wind gusts, hail, heavy downpours, and frequent lightning. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...None. NY...None. && SYNOPSIS...Evenson NEAR TERM...Evenson SHORT TERM...Lahiff LONG TERM...Lahiff AVIATION...Evenson MARINE...Evenson
Hazardous Weather Outlook National Weather Service Burlington VT 321 AM EDT Mon Jun 21 2021 NYZ026>031-034-035-087-VTZ001>012-016>019-220730- 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-Windsor- Eastern Franklin-Eastern Chittenden-Eastern Addison-Eastern Rutland- 321 AM EDT Mon Jun 21 2021 This Hazardous Weather Outlook is for northern New York, central Vermont, northeast Vermont, northwest Vermont and southern Vermont. .DAY ONE...Today and tonight. Strong to severe thunderstorms are expected across much of northern New York and Vermont this afternoon and evening. Strong wind gusts, hail, very heavy downpours, and lightning will be the main threats with any of the storms. Storms are expected to develop over the Saint Lawrence Valley and northern Adirondacks of New York by early this afternoon and move eastward across the remainder of northern New York and Vermont during the late afternoon and evening hours. The storms will exit to our south and east by midnight tonight. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday. Hazardous weather is not expected at this time. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time.
Special Weather Statement
National Weather Service Burlington VT
208 PM EDT Mon Jun 21 2021
NYZ026-029-030-087-211915-
Northern St. Lawrence-Southeastern St. Lawrence-Southern
Franklin-Southwestern St. Lawrence-
208 PM EDT Mon Jun 21 2021
...AN AREA OF STRONG THUNDERSTORMS WILL AFFECT WEST CENTRAL FRANKLIN
AND ST. LAWRENCE COUNTIES...
At 208 PM EDT, strong thunderstorms were clustered over Gouverneur,
moving northeast at 45 mph.
Wind gusts up to 50 mph and nickel size hail are possible with this
storm.
Locations impacted include...
Potsdam, Massena, Gouverneur, Ogdensburg, Canton, Norfolk, Lisbon,
Louisville, De Kalb, Fowler, Parishville, Colton, Morley, Degrasse,
Massena International Airport - Richards Field, Carry Falls
Reservoir, Waddington, Richville, Hammond and Madrid.
This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.
LAT...LON 4445 7576 4445 7578 4451 7575 4477 7541
4478 7540 4488 7522 4489 7517 4487 7516
4493 7508 4493 7501 4497 7493 4497 7496
4499 7490 4498 7492 4498 7487 4454 7444
4416 7532 4440 7582
TIME...MOT...LOC 1808Z 231DEG 39KT 4432 7550
NeilesPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BURLINGTON VT
228 PM EDT MON JUN 21 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0150 PM TSTM WND DMG 1 W FORT COVINGTON 44.98N 74.49W
06/21/2021 FRANKLIN NY PUBLIC
SEVERAL TREES REPORTED DOWN ON HOPKINS POINT ROAD IN
CONVINGTON BY TOWN GARAGE. SEVERAL OTHER STREETS HAD
TREES DOWN AS WELL.
&&
EVENT NUMBER BTV2101020
CLAYPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BURLINGTON VT
302 PM EDT MON JUN 21 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0244 PM TSTM WND DMG SOUTH EDWARDS 44.27N 75.21W
06/21/2021 ST. LAWRENCE NY LAW ENFORCEMENT
TREES REPORTED DOWN IN SOUTH EDWARDS AND FINE. POWER
OUTAGES ALSO REPORTED IN THESE LOCATIONS.
&&
EVENT NUMBER BTV2101021
CLAYSpecial Weather Statement National Weather Service Burlington VT 307 PM EDT Mon Jun 21 2021 VTZ002-005-006-016-211930- Western Franklin-Western Chittenden-Eastern Franklin-Lamoille- 307 PM EDT Mon Jun 21 2021 ...A STRONG THUNDERSTORM WILL AFFECT NORTHWESTERN LAMOILLE...NORTH CENTRAL CHITTENDEN AND SOUTH CENTRAL FRANKLIN COUNTIES... At 306 PM EDT, a strong thunderstorm was located near Milton, moving northeast at 40 mph. Winds in excess of 40 mph and pea size hail are possible with this storm. Locations impacted include... Bakersfield, Fairfax, Fletcher, Fairfield, Westford, Milton, Sheldon, Colchester, Essex, Georgia, Waterville, East Fairfield, Binghamville, East Georgia, Chimney Corner, West Fletcher and Mallets Bay State Park. LAT...LON 4452 7313 4458 7320 4488 7293 4478 7274 TIME...MOT...LOC 1906Z 219DEG 35KT 4463 7309 Kutikoff
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BURLINGTON VT
329 PM EDT MON JUN 21 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0150 PM TSTM WND DMG FORT COVINGTON 44.98N 74.47W
06/21/2021 FRANKLIN NY BROADCAST MEDIA
MEDIA RELAYED REPORTS OF A SEVERELY DAMAGED BARN
BUILDING, SEVERAL TREES UPROOTED AND SNAPPED AND A
DAMAGED VEHICLE IN FORT COVINGTON.
&&
EVENT NUMBER BTV2101022
CLAYSpecial Weather Statement National Weather Service Burlington VT 347 PM EDT Mon Jun 21 2021 VTZ003-005-006-008-016-017-212045- Eastern Chittenden-Western Chittenden-Washington-Eastern Franklin-Orleans-Lamoille- 347 PM EDT Mon Jun 21 2021 ...A STRONG THUNDERSTORM WILL AFFECT LAMOILLE...SOUTHWESTERN ORLEANS...EAST CENTRAL CHITTENDEN...NORTHWESTERN WASHINGTON AND SOUTHEASTERN FRANKLIN COUNTIES... At 347 PM EDT, a strong thunderstorm was located near Jericho, moving northeast at 35 mph. Locations impacted include... Morrisville, Johnson Village, Eden, Cambridge, Cambridge Village, Stowe, Glover, Montgomery Center, Albany, Jeffersonville Village, Hyde Park, Montgomery, Wolcott, Belvidere Center, Bolton, Belvidere, Richmond, Waterville, Underhill and Jericho. LAT...LON 4432 7290 4445 7307 4496 7255 4471 7215 TIME...MOT...LOC 1947Z 226DEG 31KT 4446 7291 Neiles
The Burlington radar (KCXX), 49 km away, was scanning. The volume nearest the first event began at 19:54 UTC.
8 thunderstorm wind, 2 hail. Local standard time, as filed.
Several trees down as well as on some utility lines between Chimney Point and Addison.
Trees and power lines downed in New Haven.
Public report of larger than quarter-size hail.
Several trees downed by thunderstorm winds between and including Fair Haven and Castleton.
Trees and powerlines downed by thunderstorms winds on Stevens road.
Trees and utility lines downed by thunderstorm winds.
Half inch to Quarter size hail fell for about 10 minutes.
Several trees and powerlines down in Tinmouth and southern Rutland.
Numerous trees and utility lines down across Norwich into Hartford.
Numerous trees and utility lines down across Hartford and Quechee.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Vermont in 2021Every state in 2021This day in weather historyWarnings in Vermont, June 2021
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 956999, 957000, 957001, 957004, 957002, 957003, 957005, 957010, 957008, 957006.