Alert archive / Pennsylvania / Mesoscale Discussions in 2013

Mesoscale Discussion 2002

November 1, 20135 states

The Storm Prediction Center issued this mesoscale discussion at Nov 1, 2013, 5:41 AM EDT for 5 states. It was in force for 94 min.

The area

The outline as issued.

The facts

Issued
Nov 1, 2013, 5:41 AM EDT (09:41 UTC)
Expired
Nov 1, 2013, 7:15 AM EDT
In force
94 min
Issued by
the Storm Prediction Center
All 59 counties

Carroll County, MD, Washington County, MD, Hunterdon County, NJ, Morris County, NJ, Somerset County, NJ, Sussex County, NJ, Warren County, NJ, Broome County, NY, Chemung County, NY, Chenango County, NY, Cortland County, NY, Delaware County, NY, Otsego County, NY, Schuyler County, NY, Steuben County, NY, Sullivan County, NY, Tioga County, NY, Tompkins County, NY, Yates County, NY, Adams County, PA, Berks County, PA, Bradford County, PA, Bucks County, PA, Carbon County, PA, Chester County, PA, Clinton County, PA, Columbia County, PA, Cumberland County, PA, Dauphin County, PA, Delaware County, PA, Franklin County, PA, Fulton County, PA, Huntingdon County, PA, Juniata County, PA, Lackawanna County, PA, Lancaster County, PA, Lebanon County, PA, Lehigh County, PA, Luzerne County, PA, Lycoming County, PA, Mifflin County, PA, Monroe County, PA, Montgomery County, PA, Montour County, PA, Northampton County, PA, Northumberland County, PA, Perry County, PA, Philadelphia County, PA, Pike County, PA, Schuylkill County, PA, Snyder County, PA, Sullivan County, PA, Susquehanna County, PA, Tioga County, PA, Union County, PA, Wayne County, PA, Wyoming County, PA, York County, PA, Morgan County, WV

The radar

The Binghamton radar (KBGM), 118 km from the middle of the area, began a volume at 09:41 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

Washington/Dulle, VA (KIAD), launched 00:00Z, 9.7 hours before the alert went out and 262 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, Washington/Dulle, VA at 00:00Z on 2013-11-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 5 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, Washington/Dulle, VA at 00:00Z on 2013-11-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 324 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
5 J/kg
Mixed-layer CIN
-16 J/kg
Mixed-layer LCL
1071 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
324 m²/s²
0-3 km storm-relative helicity
479 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Nov 1, 12:46 AM EDTSevere Thunderstorm WatchSPCGarrett5 hr
Nov 1, 3:37 AM EDTMesoscale DiscussionSPCAllegany, Carroll, Frederick, Garrett, Washington83 min
Nov 1, 4:17 AM EDTSevere Thunderstorm WatchSPCAllegany, Carroll, Frederick, Washington4 hr
Nov 1, 6:25 AM EDTSevere Thunderstorm WatchSPCAtlantic, Burlington, Camden, Cumberland, Gloucester, Hunterdon and 9 more5 hr
Nov 1, 8:34 AM EDTMesoscale DiscussionSPCEssex, Hunterdon, Mercer, Middlesex, Morris, Passaic and 3 more86 min
Nov 1, 10:39 AM EDTMesoscale DiscussionSPCAtlantic, Ocean96 min
Oct 31, 10:09 PM EDTSevere Thunderstorm WatchSPCCrawford, Erie6 hr
Nov 1, 12:39 AM EDTMesoscale DiscussionSPCCrawford96 min

Nearby

Mesoscale Discussions in Pennsylvania, 2013Mesoscale Discussions in New York, 2013Mesoscale Discussions in New Jersey, 2013Every mesoscale discussion in 2013

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.