Alert archive / Ohio / Mesoscale Discussions in 2019

Mesoscale Discussion 749

May 23, 20194 counties in New York; 10 counties in Ohio; 10 counties in Pennsylvania

The Storm Prediction Center issued this mesoscale discussion at May 23, 2019, 8:53 AM EDT for 4 counties in New York; 10 counties in Ohio; 10 counties in Pennsylvania. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: May 23, 2019, 8:53 AM EDT (12:53 UTC)
Expired: May 23, 2019, 11:00 AM EDT
In force: 2 hr
Issued by: the Storm Prediction Center
Chance of a watch: 40%

All 24 counties

Cattaraugus County, NY, Chautauqua County, NY, Erie County, NY, Wyoming County, NY, Ashtabula County, OH, Carroll County, OH, Columbiana County, OH, Geauga County, OH, Holmes County, OH, Mahoning County, OH, Portage County, OH, Stark County, OH, Summit County, OH, Trumbull County, OH, Beaver County, PA, Butler County, PA, Clarion County, PA, Crawford County, PA, Erie County, PA, Forest County, PA, Lawrence County, PA, Mercer County, PA, Venango County, PA, Warren County, PA

The radar

The Pittsburgh radar (KPBZ), 131 km from the middle of the area, began a volume at 12:54 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

Severe Thunderstorm Watch 217May 23, 9:40 AM EDT

The nearest sounding before it

Pittsburgh, PA (KAGC), launched 12:00Z, 0.9 hours before the alert went out and 146 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: 539 J/kg
Mixed-layer CIN: -70 J/kg
Mixed-layer LCL: 1211 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 206 m²/s²
0-3 km storm-relative helicity: 129 m²/s²
Significant tornado parameter: 0.4
Supercell composite: 3.7

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
May 23, 9:39 AM EDT	Severe Thunderstorm Watch	SPC	Allegany, Cattaraugus, Cayuga, Chautauqua, Chemung, Cortland and 17 more	3 hr
May 23, 6:47 PM EDT	Mesoscale Discussion	SPC	Cayuga, Hamilton, Herkimer, Lewis, Madison, Monroe and 6 more	118 min
May 23, 7:10 PM EDT	Mesoscale Discussion	SPC	Allegany, Broome, Chemung, Chenango, Cortland, Livingston and 5 more	65 min
May 23, 4:50 AM EDT	Mesoscale Discussion	SPC	Defiance, Paulding, Van Wert, Williams	55 min
May 23, 3:39 PM EDT	Mesoscale Discussion	SPC	Adams, Brown, Butler, Clermont, Clinton, Hamilton and 6 more	96 min
May 23, 5:37 PM EDT	Severe Thunderstorm Watch	SPC	Adams, Athens, Belmont, Brown, Clinton, Fairfield and 21 more	5 hr
May 23, 5:44 PM EDT	Mesoscale Discussion	SPC	Adams, Athens, Belmont, Brown, Clermont, Clinton and 22 more	61 min
May 23, 11:52 AM EDT	Mesoscale Discussion	SPC	Adams, Bedford, Blair, Cambria, Centre, Clinton and 18 more	83 min
May 23, 1:02 PM EDT	Severe Thunderstorm Watch	SPC	Adams, Berks, Chester, Cumberland, Dauphin, Franklin and 6 more	5 hr

Nearby

Mesoscale Discussions in Ohio, 2019 Mesoscale Discussions in Pennsylvania, 2019 Mesoscale Discussions in New York, 2019 Every mesoscale discussion in 2019

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.