Alert archive / Vermont / Mesoscale Discussions in 2021

Mesoscale Discussion 1357

July 26, 20214 counties in New York; 10 counties in Vermont

The Storm Prediction Center issued this mesoscale discussion at Jul 26, 2021, 6:03 PM EDT for 4 counties in New York; 10 counties in Vermont. It was in force for 87 min.

The area

The outline as issued.

The facts

Issued
Jul 26, 2021, 6:03 PM EDT (22:03 UTC)
Expired
Jul 26, 2021, 7:30 PM EDT
In force
87 min
Issued by
the Storm Prediction Center
Concerning
Severe potential...watch unlikely
Chance of a watch
5%

Counties Clinton County, NY, Essex County, NY, Franklin County, NY, St. Lawrence 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, Washington County, VT

The radar

The Burlington radar (KCXX), 25 km from the middle of the area, began a volume at 22:07 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, 10.1 hours before the alert went out and 193 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 2021-07-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2021-07-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 69 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1102 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
69 m²/s²
0-3 km storm-relative helicity
88 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

536 
ACUS11 KWNS 262203
SWOMCD
SPC MCD 262203 
NHZ000-VTZ000-NYZ000-262330-

Mesoscale Discussion 1357
NWS Storm Prediction Center Norman OK
0503 PM CDT Mon Jul 26 2021

Areas affected...Northern New York and Vermont

Concerning...Severe potential...Watch unlikely 

Valid 262203Z - 262330Z

Probability of Watch Issuance...5 percent

SUMMARY...Isolated large hail or a damaging wind gust is possible
this evening.

DISCUSSION...Storms have developed in eastern Ontario and St.
Lawrence counties over the past few hours. These storms have stayed
below severe limits thus far and are mostly expected to remain that
way given the somewhat weak shear and MLCAPE only around 500 to 1000
J/kg. If storms congeal/collide, a stronger updraft may be possible
which could pose a threat for isolated damaging winds/large hail.
Overall, expect most of these storms to produce sub-severe
winds/hail over the next few hours.

..Bentley/Grams.. 07/26/2021

...Please see www.spc.noaa.gov for graphic product...

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

LAT...LON   45027491 45057306 45047241 45037177 44907161 44687162
            44337192 44047205 43757235 43717310 43647354 43757472
            43927538 44207574 44417601 45027491

Nearby

Mesoscale Discussions in Vermont, 2021Mesoscale Discussions in New York, 2021Every mesoscale discussion in 2021

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.