Alert archive / Vermont / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 20, NWS Burlington, VT

July 20, 20154 counties in Vermont

NWS Burlington, VT issued this severe thunderstorm warning at Jul 20, 2015, 1:24 AM EDT for 4 counties in Vermont. It was in force for 66 min. 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 20, 2015, 1:24 AM EDT (05:24 UTC)
Expired
Jul 20, 2015, 2:30 AM EDT
In force
66 min
Issued by
NWS Burlington, VT
Area
Storm-based polygon

Counties Addison County, VT, Chittenden County, VT, Orange County, VT, Washington County, VT

The radar

The Burlington radar (KCXX), 46 km from the middle of the area, began a volume at 05:27 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

Albany, NY (KALY), launched 00:00Z, 5.4 hours before the alert went out and 187 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, Albany, NY at 00:00Z on 2015-07-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 553 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Albany, NY at 00:00Z on 2015-07-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 228 square meters per square second.19395878Sfc1 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
553 J/kg
Mixed-layer CIN
-153 J/kg
Mixed-layer LCL
1152 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
228 m²/s²
0-3 km storm-relative helicity
282 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-0.2

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm 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 severe thunderstorm warning went out at Jul 20, 1:19 AM EDT, 5 minutes earlier.

Area forecast discussion, Jul 20, 1:19 AM EDT, 5 minutes before
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Hazardous weather outlook, Jul 19, 10:43 PM EDT, 2 hours 41 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BURLINGTON VT
1043 PM EDT SUN JUL 19 2015

NYZ026>031-034-035-087-VTZ001>012-016>019-210245-
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-
1043 PM EDT SUN JUL 19 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHERN NEW YORK...CENTRAL
VERMONT...NORTHEAST VERMONT...NORTHWEST VERMONT AND SOUTHERN
VERMONT.

.DAY ONE...TONIGHT.

ISOLATED TO SCATTERED THUNDERSTORMS WILL CONTINUE ACROSS THE AREA
THROUGH THE EARLY MORNING HOURS BEFORE COMING TO AN END. MODERATE
TO HEAVY DOWNPOURS WILL BE POSSIBLE WITH ANY OF THE STORMS.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

In the hours before

Local storm report, Jul 19, 9:45 PM EDT, 3 hours 39 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BURLINGTON VT
945 PM EDT SUN JUL 19 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0915 PM     TSTM WND DMG     BRUNSWICK SPRINGS       44.74N  71.63W
07/19/2015                   ESSEX              VT   PUBLIC

            TREE DOWN ON A HOUSE.

&&

EVENT NUMBER BTV1500962

LOCONTO
Local storm report, Jul 19, 10:28 PM EDT, 2 hours 56 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BURLINGTON VT
1028 PM EDT SUN JUL 19 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1026 PM     FLASH FLOOD      BARRE                   44.20N  72.51W
07/19/2015                   WASHINGTON         VT   AMATEUR RADIO

            CUMMINGS ROAD... MITCHELL AVE... MAPLE AVE AND
            PLAINFIELD BROOK ST IN BARRE ARE CLOSED DUE TO FLASH
            FLOODING.

&&

EVENT NUMBER BTV1500963

LOCONTO
Local storm report, Jul 19, 10:29 PM EDT, 2 hours 55 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BURLINGTON VT
1029 PM EDT SUN JUL 19 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1028 PM     FLASH FLOOD      BARRE                   44.20N  72.51W
07/19/2015                   WASHINGTON         VT   AMATEUR RADIO

            2 TO 3 FEET OF WATER COVERS HARRINGTON AVE IN BARRE.

&&

EVENT NUMBER BTV1500964

LOCONTO
Special weather statement, Jul 19, 10:44 PM EDT, 2 hours 40 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BURLINGTON VT
1044 PM EDT SUN JUL 19 2015

NYZ028-VTZ001>003-016-200345-
EASTERN CLINTON-EASTERN FRANKLIN-ORLEANS-GRAND ISLE-WESTERN FRANKLIN-
1044 PM EDT SUN JUL 19 2015

...A STRONG THUNDERSTORM WILL AFFECT NORTHERN CLINTON COUNTY IN NEW
YORK AND GRAND ISLE...NORTHERN FRANKLIN AND NORTHERN ORLEANS
COUNTIES IN VERMONT...

AT 1039 PM EDT...A STRONG THUNDERSTORM WAS OVER CHAZY...MOVING EAST
AT 50 MPH.

WINDS IN EXCESS OF 40 MPH...PEA SIZE HAIL AND HEAVY DOWNPOURS ARE
POSSIBLE WITH THIS STORM.

LOCATIONS TO BE IMPACTED INCLUDE...
FRANKLIN...CHAZY...RICHFORD...SHELDON...BERKSHIRE...TROY...ENOSBURG
FALLS...MONTGOMERY...NORTH HERO...WESTFIELD...JAY...ISLE LA MOTTE...
LAKE CARMI STATE PARK...ALBURGH...ALBURGH DUNES STATE
PARK...HIGHGATE FALLS...MONTGOMERY CENTER...SOUTH ALBURGH AND
NEWPORT CENTER.

BOATERS ON THE NORTHERN END OF LAKE CHAMPLAIN SHOULD SEEK SAFE
HARBOR IMMEDIATELY.

FREQUENT LIGHTNING IS OCCURRING WITH THIS STORM. LIGHTNING CAN
STRIKE 15 MILES AWAY FROM A THUNDERSTORM. SEEK A SAFE SHELTER INSIDE
A BUILDING OR VEHICLE.

LAT...LON 4500 7231 4485 7228 4478 7348 4496 7352
      4501 7313
TIME...MOT...LOC 0239Z 261DEG 42KT 4489 7341

LOCONTO
Local storm report, Jul 19, 10:55 PM EDT, 2 hours 29 minutes before
PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE BURLINGTON VT
1055 PM EDT SUN JUL 19 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0400 PM     HAIL             WASHINGTON              44.11N  72.43W
07/19/2015  E0.25 INCH       ORANGE             VT   PUBLIC

0415 PM     HAIL             ST. ALBANS              44.81N  73.08W
07/19/2015  E0.25 INCH       FRANKLIN           VT   PUBLIC

0423 PM     HAIL             ST. ALBANS              44.81N  73.08W
07/19/2015  E0.75 INCH       FRANKLIN           VT   PUBLIC

0442 PM     HAIL             2 N CHELSEA             44.02N  72.45W
07/19/2015  M1.00 INCH       ORANGE             VT   PUBLIC

            HAIL REPORTED TO BROADCAST MEDIA

0542 PM     TSTM WND DMG     WOLCOTT                 44.55N  72.46W
07/19/2015                   LAMOILLE           VT   PUBLIC

            REPORT OF A TREE DOWN IN WOLCOTT FROM THE STORMS
            EARLIER THIS AFTERNOON. TIME ESTIMATED BY RADAR.

0615 PM     HAIL             3 S LYNDONVILLE         44.49N  72.00W
07/19/2015  E1.00 INCH       CALEDONIA          VT   PUBLIC

            QUARTER-SIZED HAIL ACCOMPANIED HEAVY DOWNPOUR. TIME
            ESTIMATED BY RADAR.

0805 PM     FLASH FLOOD      HARDWICK                44.50N  72.37W
07/19/2015                   CALEDONIA          VT   PUBLIC

            REPORT OF WATER 6-8 INCHES DEEP ALONG ROUTE 14 AND 15
            NEAR THE FIRE DEPARTMENT IN DOWNTOWN HARDWICK

0850 PM     FLASH FLOOD      EAST MONTPELIER         44.27N  72.49W
07/19/2015                   WASHINGTON         VT   PUBLIC

            WATER COVERING PARTS OF ROUTE 14 IN EAST MONTPELIER.

0850 PM     HAIL             NEWARK                  44.70N  71.93W
07/19/2015  E1.00 INCH       CALEDONIA          VT   PUBLIC

            ALSO SEVERAL LIMBS DOWN

0900 PM     FLASH FLOOD      BARRE                   44.20N  72.51W
07/19/2015                   WASHINGTON         VT   LAW ENFORCEMENT

            MAIN STREET IN BARRE CLOSED TO FLASH FLOODING

0909 PM     FLASH FLOOD      PLAINFIELD              44.28N  72.43W
07/19/2015                   WASHINGTON         VT   PUBLIC

            WATER COVERING GREAT BROOK ROAD IN PLAINFIELD. AND
            BRIDGE WASHOUT

0915 PM     TSTM WND DMG     BRUNSWICK SPRINGS       44.74N  71.63W
07/19/2015                   ESSEX              VT   PUBLIC

            TREE DOWN ON A HOUSE.

1026 PM     FLASH FLOOD      BARRE                   44.20N  72.51W
07/19/2015                   WASHINGTON         VT   AMATEUR RADIO

            CUMMINGS ROAD... MITCHELL AVE... MAPLE AVE AND
            PLAINFIELD BROOK ST IN BARRE ARE CLOSED DUE TO FLASH
            FLOODING.

1028 PM     FLASH FLOOD      BARRE                   44.20N  72.51W
07/19/2015                   WASHINGTON         VT   AMATEUR RADIO

            2 TO 3 FEET OF WATER COVERS HARRINGTON AVE IN BARRE.

&&

EVENT NUMBER BTV1500950 BTV1500952 BTV1500953 BTV1500954 BTV1500957
BTV1500955 BTV1500956 BTV1500958 BTV1500960 BTV1500961 BTV1500959
BTV1500962 BTV1500963 BTV1500964

LOCONTO
Special weather statement, Jul 20, 12:21 AM EDT, 1 hour 3 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BURLINGTON VT
1221 AM EDT MON JUL 20 2015

NYZ028-030-031-034-035-VTZ001-002-005-009-011-016>018-200515-
WESTERN CLINTON-WESTERN ESSEX-SOUTHERN FRANKLIN-EASTERN
CLINTON-EASTERN ESSEX-EASTERN FRANKLIN-EASTERN ADDISON-WESTERN
ADDISON-WESTERN CHITTENDEN-EASTERN CHITTENDEN-GRAND ISLE-WESTERN
RUTLAND-WESTERN FRANKLIN-
1221 AM EDT MON JUL 20 2015

...A LINE OF STRONG THUNDERSTORMS WILL AFFECT THE NORTHERN CHAMPLAIN
VALLEY...

AT 1216 AM EDT...A DEVELOPING LINE OF STRONG THUNDERSTORMS EXTENDED
FROM NEAR ADIRONDACK REGIONAL AIRPORT TO NEAR BLUE MOUNTAIN LAKE TO
10 MILES SOUTHWEST OF LAKE PLEASANT...AND MOVING EAST AT 50 MPH.

WINDS IN EXCESS OF 40 MPH...FREQUENT LIGHTNING AND HEAVY RAIN ARE
POSSIBLE WITH THESE STORMS.

LOCATIONS TO BE IMPACTED INCLUDE...
SOUTH BURLINGTON...COLCHESTER...ESSEX JUNCTION...BRISTOL...BURLINGTON
INTERNATIONAL AIRPORT...ADIRONDACK REGIONAL AIRPORT...ESSEX...
ADDISON...WILLISTON...WINOOSKI...SHELBURNE...PERU...JERICHO...
HINESBURG...FAIRFAX...CHARLOTTE...FERRISBURGH...WESTFORD...WILLSBORO
AND CROWN POINT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

BOATERS ON LAKE CHAMPLAIN SHOULD SEEK SAFE HARBOR. THUNDERSTORMS CAN
PRODUCE SUDDEN WAVES.

LAT...LON 4473 7290 4355 7325 4358 7330 4363 7331
      4363 7337 4357 7340 4359 7343 4362 7342
      4364 7343 4377 7335 4381 7338 4374 7406
      4380 7405 4381 7412 4383 7415 4381 7422
      4393 7434 4397 7426 4412 7429 4442 7420
TIME...MOT...LOC 0416Z 255DEG 45KT 4434 7428 4392 7440 4336 7455

LOCONTO

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 19, 8:26 PM EDTFlash Flood WarningBTVCaledonia, Lamoille, Orleans, Washington8 hr
Jul 19, 8:48 PM EDTSevere Thunderstorm WarningBTVCaledonia, Essex, Orleans57 min
Jul 19, 10:44 PM EDTSpecial Weather StatementBTVFranklin, Grand Isle61 min
Jul 20, 12:21 AM EDTSpecial Weather StatementBTVAddison, Chittenden54 min
Jul 20, 1:57 AM EDTSpecial Weather StatementBTVChittenden, Washington63 min
Jul 20, 2:22 AM EDTSpecial Weather StatementBTVOrange38 min
Jul 20, 4:09 AM EDTAreal Flood WarningBTVCaledonia, Orange6 hr

Nearby

Severe Thunderstorm Warnings in Vermont, 2015Every severe thunderstorm warning in 2015

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.