Alert archive / New York / Mesoscale Discussions in 2020

Mesoscale Discussion 1244

July 16, 20209 counties in New York; 9 counties in Pennsylvania

The Storm Prediction Center issued this mesoscale discussion at Jul 16, 2020, 7:51 PM EDT for 9 counties in New York; 9 counties in Pennsylvania. It was in force for 54 min.

The area

The outline as issued.

The facts

Issued: Jul 16, 2020, 7:51 PM EDT (23:51 UTC)
Expired: Jul 16, 2020, 8:45 PM EDT
In force: 54 min
Issued by: the Storm Prediction Center
Concerning: Severe thunderstorm watch 378

Counties Allegany County, NY, Cattaraugus County, NY, Erie County, NY, Genesee County, NY, Livingston County, NY, Monroe County, NY, Ontario County, NY, Wayne County, NY, Wyoming County, NY, Cameron County, PA, Clarion County, PA, Clearfield County, PA, Elk County, PA, Forest County, PA, Jefferson County, PA, McKean County, PA, Potter County, PA, Warren County, PA

The radar

The State College radar (KCCX), 109 km from the middle of the area, began a volume at 23:53 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

Buffalo Intl Airport, NY (KBUF), launched 12:00Z, 11.9 hours before the alert went out and 139 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: 12 J/kg
Mixed-layer CIN: -260 J/kg
Mixed-layer LCL: 1469 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: 171 m²/s²
0-3 km storm-relative helicity: 161 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
Jul 16, 12:18 PM EDT	Mesoscale Discussion	SPC	Allegany, Cattaraugus, Chautauqua, Erie, Genesee, Livingston and 1 more	117 min
Jul 16, 1:20 PM EDT	Severe Thunderstorm Watch	SPC	Allegany, Cattaraugus, Chautauqua, Erie, Genesee, Livingston and 6 more	8 hr
Jul 16, 3:51 PM EDT	Mesoscale Discussion	SPC	Allegany, Cattaraugus, Chautauqua, Erie, Genesee, Livingston and 5 more	84 min

Nearby

Mesoscale Discussions in New York, 2020 Mesoscale Discussions in Pennsylvania, 2020 Every mesoscale discussion in 2020

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.