Alert archive / Vermont / Flash Flood Watches in 2009

Flash Flood Watch 3, NWS Burlington, VT

July 29, 200911 counties in Vermont; Clinton County, Essex County, New York

NWS Burlington, VT issued this flash flood watch at Jul 29, 2009, 2:28 PM EDT for 11 counties in Vermont; Clinton County, Essex County, New York. It took effect at Jul 29, 2009, 4:00 PM EDT. It was in force for 13 hr.

The area

The counties it named.

The facts

Issued
Jul 29, 2009, 2:28 PM EDT (18:28 UTC)
In effect from
Jul 29, 2009, 4:00 PM EDT
Expired
Jul 30, 2009, 5:12 AM EDT
In force
13 hr
Issued by
NWS Burlington, VT
Flood severity
None

Counties Clinton County, NY, Essex County, NY, Addison County, VT, Caledonia County, VT, Chittenden County, VT, Essex County, VT, Franklin County, VT, Grand Isle County, VT, Lamoille County, VT, Orange County, VT, Orleans County, VT, Rutland County, VT, Washington County, VT

The radar

The Burlington radar (KCXX), 29 km from the middle of the area, began a volume at 18:31 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 12:00Z, 6.5 hours before the alert went out and 209 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 12:00Z on 2009-07-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 362 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 12:00Z on 2009-07-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 78 square meters per square second.193958Sfc1 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
362 J/kg
Mixed-layer CIN
-58 J/kg
Mixed-layer LCL
826 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
78 m²/s²
0-3 km storm-relative helicity
65 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.2

Open this sounding in Storm Lab

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 29, 2:54 PM EDTSpecial Weather StatementBTVRutland51 min
Jul 29, 3:07 PM EDTSpecial Weather StatementBTVWindsor53 min
Jul 29, 3:42 PM EDTSpecial Weather StatementBTVAddison63 min
Jul 29, 3:53 PM EDTSpecial Weather StatementBTVOrange, Windsor52 min
Jul 29, 4:20 PM EDTSpecial Weather StatementBTVChittenden55 min
Jul 29, 4:50 PM EDTSpecial Weather StatementBTVChittenden, Franklin, Grand Isle55 min
Jul 29, 5:04 PM EDTAreal Flood AdvisoryBTVRutland3 hr
Jul 29, 5:23 PM EDTSpecial Weather StatementBTVGrand Isle52 min
Jul 29, 5:50 PM EDTSpecial Weather StatementBTVOrleans55 min
Jul 29, 5:59 PM EDTSpecial Weather StatementBTVChittenden, Franklin, Grand Isle, Lamoille61 min
Jul 29, 6:25 PM EDTFlash Flood WarningBTVRutland6 hr
Jul 29, 3:17 PM EDTSpecial Weather StatementBTVEssex58 min
Jul 29, 6:32 PM EDTAreal Flood AdvisoryBTVClinton7 hr

Nearby

Flash Flood Watches in Vermont, 2009Flash Flood Watches in New York, 2009Every flash flood watch 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.