Alert archive / Vermont / Mesoscale Discussions in 2018

Mesoscale Discussion 1502

September 26, 20184 states

The Storm Prediction Center issued this mesoscale discussion at Sep 26, 2018, 2:43 PM EDT for 4 states. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Sep 26, 2018, 2:43 PM EDT (18:43 UTC)
Expired: Sep 26, 2018, 4:45 PM EDT
In force: 2 hr
Issued by: the Storm Prediction Center
Chance of a watch: 60%

All 31 counties

Franklin County, ME, Oxford County, ME, Belknap County, NH, Carroll County, NH, Coos County, NH, Grafton County, NH, Merrimack County, NH, Sullivan County, NH, Clinton County, NY, Essex County, NY, Franklin County, NY, Fulton County, NY, Hamilton County, NY, Herkimer County, NY, Montgomery County, NY, Saratoga County, NY, Warren County, NY, Washington County, NY, Addison County, VT, Bennington 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), 34 km from the middle of the area, began a volume at 18:43 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, 6.7 hours before the alert went out and 185 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 11 J/kg
Mixed-layer CIN: -202 J/kg
Mixed-layer LCL: 598 m above ground
0-6 km bulk shear: 48 kt
0-1 km storm-relative helicity: 261 m²/s²
0-3 km storm-relative helicity: 345 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Sep 26, 2:48 PM EDT	Mesoscale Discussion	SPC	Albany, Broome, Chemung, Chenango, Columbia, Cortland and 8 more	2 hr

Nearby

Mesoscale Discussions in Vermont, 2018 Mesoscale Discussions in New York, 2018 Mesoscale Discussions in New Hampshire, 2018 Every mesoscale discussion in 2018

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.