Alert archive / Pennsylvania / Mesoscale Discussions in 2018

Mesoscale Discussion 1514

October 2, 20185 states

The Storm Prediction Center issued this mesoscale discussion at Oct 2, 2018, 4:43 PM EDT for 5 states. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Oct 2, 2018, 4:43 PM EDT (20:43 UTC)
Expired
Oct 2, 2018, 6:45 PM EDT
In force
2 hr
Issued by
the Storm Prediction Center
All 63 counties

Warren County, NJ, Sullivan County, NY, Ashtabula County, OH, Columbiana County, OH, Jefferson County, OH, Mahoning County, OH, Trumbull County, OH, Allegheny County, PA, Armstrong County, PA, Beaver County, PA, Berks County, PA, Blair County, PA, Bradford County, PA, Butler County, PA, Cambria County, PA, Cameron County, PA, Carbon County, PA, Centre County, PA, Clarion County, PA, Clearfield County, PA, Clinton County, PA, Columbia County, PA, Crawford County, PA, Cumberland County, PA, Dauphin County, PA, Elk County, PA, Erie County, PA, Forest County, PA, Huntingdon County, PA, Indiana County, PA, Jefferson County, PA, Juniata County, PA, Lackawanna County, PA, Lawrence County, PA, Lebanon County, PA, Lehigh County, PA, Luzerne County, PA, Lycoming County, PA, McKean County, PA, Mercer County, PA, Mifflin County, PA, Monroe County, PA, Montour County, PA, Northampton County, PA, Northumberland County, PA, Perry County, PA, Pike County, PA, Potter County, PA, Schuylkill County, PA, Snyder County, PA, Sullivan County, PA, Susquehanna County, PA, Tioga County, PA, Union County, PA, Venango County, PA, Warren County, PA, Washington County, PA, Wayne County, PA, Westmoreland County, PA, Wyoming County, PA, Brooke County, WV, Hancock County, WV, Ohio County, WV

The radar

The State College radar (KCCX), 24 km from the middle of the area, began a volume at 20:44 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.

The nearest sounding before it

Pittsburgh, PA (KAGC), launched 12:00Z, 8.7 hours before the alert went out and 165 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, Pittsburgh, PA at 12:00Z on 2018-10-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 779 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, Pittsburgh, PA at 12:00Z on 2018-10-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 120 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
779 J/kg
Mixed-layer CIN
-35 J/kg
Mixed-layer LCL
821 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
120 m²/s²
0-3 km storm-relative helicity
133 m²/s²
Significant tornado parameter
0.4
Supercell composite
2.7

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.

IssuedProductOfficeCountiesLasted
Oct 2, 3:10 PM EDTMesoscale DiscussionSPCBergen, Essex, Hudson, Hunterdon, Middlesex, Morris and 5 more2 hr
Oct 2, 4:57 PM EDTTornado WatchSPCBergen, Essex, Morris, Passaic, Sussex, Warren7 hr
Oct 2, 7:24 PM EDTMesoscale DiscussionSPCBergen, Passaic, Sussex81 min
Oct 2, 2:55 PM EDTTornado WatchSPCSullivan8 hr
Oct 2, 4:05 PM EDTMesoscale DiscussionSPCAllegany, Cattaraugus, Chautauqua, Erie, Livingston, Ontario and 5 more115 min
Oct 2, 2:26 PM EDTMesoscale DiscussionSPCBelmont, Carroll, Columbiana, Harrison, Jefferson, Mahoning and 5 more2 hr
Oct 2, 2:55 PM EDTMesoscale DiscussionSPCAshland, Auglaize, Champaign, Clark, Clinton, Coshocton and 33 more2 hr
Oct 2, 3:29 PM EDTSevere Thunderstorm WatchSPCAshland, Athens, Belmont, Carroll, Champaign, Clark and 35 more6 hr
Oct 2, 4:49 PM EDTMesoscale DiscussionSPCAshland, Athens, Belmont, Carroll, Champaign, Clark and 51 more116 min
Oct 2, 7:34 PM EDTMesoscale DiscussionSPCAthens, Belmont, Carroll, Coshocton, Fairfield, Franklin and 14 more86 min

Nearby

Mesoscale Discussions in Pennsylvania, 2018Mesoscale Discussions in Ohio, 2018Mesoscale Discussions in West Virginia, 2018Every 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.