Alert archive / Vermont / Mesoscale Discussions in 2011

Mesoscale Discussion 1007

May 28, 2011Clinton County, Essex County, New York; 12 counties in Vermont

The Storm Prediction Center issued this mesoscale discussion at May 28, 2011, 5:37 PM EDT for Clinton County, Essex County, New York; 12 counties in Vermont. It was in force for 53 min.

The area

The outline as issued.

The facts

Issued
May 28, 2011, 5:37 PM EDT (21:37 UTC)
Expired
May 28, 2011, 6:30 PM EDT
In force
53 min
Issued by
the Storm Prediction Center

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, Windsor County, VT

The radar

The Burlington radar (KCXX), 22 km from the middle of the area, began a volume at 21:40 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, 9.6 hours before the alert went out and 189 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 2011-05-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 167 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 2011-05-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 124 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
167 J/kg
Mixed-layer CIN
-146 J/kg
Mixed-layer LCL
742 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
124 m²/s²
0-3 km storm-relative helicity
177 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

856 
ACUS11 KWNS 282137
SWOMCD
SPC MCD 282137 
NHZ000-VTZ000-NYZ000-282230-

MESOSCALE DISCUSSION 1007
NWS STORM PREDICTION CENTER NORMAN OK
0437 PM CDT SAT MAY 28 2011

AREAS AFFECTED...PORTIONS OF UPSTATE NEW YORK INTO VT

CONCERNING...SEVERE THUNDERSTORM WATCH 391...

VALID 282137Z - 282230Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 391
CONTINUES.

OCCASIONAL STRONG TO SEVERE STORMS CAPABLE OF DMGG WINDS AND LARGE
HAIL REMAIN POSSIBLE OVER THE WW AREA.

A WEAK MID LEVEL IMPULSE OBSERVED ON WV IMAGERY OVER UPSTATE NY AND
NWRN NEW ENGLAND AS OF 2130Z HAS PROVIDED SUFFICIENT UPPER FORCING
FOR CONVECTION TO DEVELOP ACROSS THE WW AREA. AS THIS WAVE QUICKLY
MOVES THROUGH...IMPLIED SUBSIDENCE IN ITS WAKE IN COMBINATION WITH
DIURNAL COOLING MAY ACT TO WEAKEN ONGOING CONVECTION. IN THE MEAN
TIME...WEAK INSTABILITY AND MODEST MID LEVEL LAPSE RATES /6.5 C/KM
PER RUC ANALYSIS/ JUXTAPOSED WITH EFFECTIVE SHEAR OF 30-40 KTS
SHOULD BE SUPPORTIVE OF LOOSELY ORGANIZED STORMS CAPABLE OF DMGG
WINDS AND LARGE HAIL.

..HURLBUT.. 05/28/2011

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...GYX...BTV...ALY...

LAT...LON   44987391 45027157 44427170 43207249 43357327 43907422
            44667402 44987391

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 28, 1:42 PM EDTMesoscale DiscussionSPCClinton, Essex, Saratoga, Warren, Washington63 min
May 28, 1:45 PM EDTSevere Thunderstorm WatchSPCClinton, Essex5 hr

Nearby

Mesoscale Discussions in Vermont, 2011Mesoscale Discussions in New York, 2011Every mesoscale discussion in 2011

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.