Alert archive / Vermont / Severe Thunderstorm Warnings in 2009
Severe Thunderstorm Warning 54, NWS Burlington, VT
NWS Burlington, VT issued this severe thunderstorm warning at Aug 21, 2009, 1:07 PM EDT for Caledonia County, Orange County, Washington County, Vermont. It was in force for 53 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
- Aug 21, 2009, 1:07 PM EDT (17:07 UTC)
- Expired
- Aug 21, 2009, 2:00 PM EDT
- In force
- 53 min
- Issued by
- NWS Burlington, VT
- Area
- Storm-based polygon
Counties Caledonia County, VT, Orange County, VT, Washington County, VT
The radar
The Burlington radar (KCXX), 70 km from the middle of the area, began a volume at 17:10 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 watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Aug 21, 10:47 AM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
The nearest sounding before it
Gray, ME (KGYX), launched 12:00Z, 5.1 hours before the alert went out and 173 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.
- Mixed-layer CAPE
- 519 J/kg
- Mixed-layer CIN
- -28 J/kg
- Mixed-layer LCL
- 454 m above ground
- 0-6 km bulk shear
- 33 kt
- 0-1 km storm-relative helicity
- 79 m²/s²
- 0-3 km storm-relative helicity
- 130 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 1.2
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 Aug 21, 11:25 AM EDT, 1 hour 42 minutes earlier.
Area forecast discussion, Aug 21, 11:25 AM EDT, 1 hour 42 minutes before
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</html>Hazardous weather outlook, Aug 21, 11:28 AM EDT, 1 hour 39 minutes before
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Special weather statement, Aug 21, 10:36 AM EDT, 2 hours 31 minutes before
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</html>Special weather statement, Aug 21, 11:40 AM EDT, 1 hour 27 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE BURLINGTON VT 1140 AM EDT FRI AUG 21 2009 VTZ009>012-018-019-211645- EASTERN ADDISON VT-EASTERN RUTLAND VT-ORANGE VT-WESTERN ADDISON VT- WESTERN RUTLAND VT-WINDSOR VT- 1140 AM EDT FRI AUG 21 2009 ...STRONG THUNDERSTORMS WILL DEVELOP ACROSS ADDISON...ORANGE...RUTLAND AND WINDSOR COUNTIES THROUGH 1 PM... AT 1137 AM EDT...A DEVELOPING CLUSTER OF THUNDERSTORMS WERE LOCATED ACROSS CENTRAL RUTLAND COUNTY...AND MOVE NORTHEAST AT 20 MPH. WIND GUSTS TO 40 MPH AND HAIL UP TO DIME SIZE ARE POSSIBLE WITH THESE STORMS. VERY HEAVY RAIN WILL FALL FROM THESE STORMS...AND WILL CAUSE WATER TO POND ON ROADS AND QUICKLY FILL ROADSIDE DITCHES AND SMALL STREAMS. THESE STORMS WILL BE NEAR PROCTOR AROUND 1145 AM...CHITTENDEN AROUND NOON...GIFFORD WOODS STATE PARK AROUND 1215 PM...PITTSFIELD AROUND 1230 PM AND ROCHESTER AROUND 1245 PM. A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 700 PM FRIDAY EVENING FOR VERMONT. LAT...LON 4410 7301 4383 7238 4347 7305 4363 7326
Special weather statement, Aug 21, 1:03 PM EDT, 4 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BURLINGTON VT
103 PM EDT FRI AUG 21 2009
VTZ007-008-010-012-211800-
CALEDONIA VT-ORANGE VT-WASHINGTON VT-WINDSOR VT-
103 PM EDT FRI AUG 21 2009
...A STRONG THUNDERSTORM WILL AFFECT CALEDONIA...ORANGE...WASHINGTON
AND WINDSOR COUNTIES...
AT 103 PM EDT...A STRONG THUNDERSTORM WAS LOCATED NEAR RANDOLPH
CENTER...MOVING NORTHEAST AT 25 MPH.
WIND GUSTS TO 50 MPH AND PEA-SIZED HAIL ARE POSSIBLE WITH THIS STORM.
THIS STORM WILL BE NEAR EAST BROOKFIELD AROUND 115 PM...WASHINGTON
AROUND 130 PM...WEST TOPSHAM AROUND 145 PM AND GROTON AROUND 200 PM.
A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 700 PM FRIDAY
EVENING FOR VERMONT.
LAT...LON 4427 7205 4423 7204 4418 7205 4416 7204
4386 7258 4399 7275 4443 7218 4430 7202The office that day
Everything else NWS Burlington, VT issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 21, 11:40 AM EDT | Special Weather Statement | BTV | Rutland | 65 min |
| Aug 21, 1:03 PM EDT | Special Weather Statement | BTV | Orange | 57 min |
| Aug 21, 1:28 PM EDT | Special Weather Statement | BTV | Rutland | 47 min |
| Aug 21, 1:42 PM EDT | Areal Flood Advisory | BTV | Addison, Orange, Rutland, Washington, Windsor | 3 hr |
| Aug 21, 2:03 PM EDT | Severe Thunderstorm Warning | BTV | Addison, Rutland, Windsor | 27 min |
| Aug 21, 2:27 PM EDT | Special Weather Statement | BTV | Windsor | 63 min |
| Aug 21, 3:07 PM EDT | Flash Flood Watch | BTV | Addison, Caledonia, Essex, Lamoille, Orange, Orleans and 2 more | 30 hr |
| Aug 21, 3:37 PM EDT | Areal Flood Warning | BTV | Orange, Windsor | 3 hr |
Nearby
Severe Thunderstorm Warnings in Vermont, 2009Every severe thunderstorm warning in 2009
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.