Alert archive / Pennsylvania / Mesoscale Discussions in 2011

Mesoscale Discussion 600

April 26, 201127 counties in New York; 35 counties in Pennsylvania

The Storm Prediction Center issued this mesoscale discussion at Apr 26, 2011, 6:51 PM EDT for 27 counties in New York; 35 counties in Pennsylvania. It was in force for 54 min.

The area

The outline as issued.

The facts

Issued
Apr 26, 2011, 6:51 PM EDT (22:51 UTC)
Expired
Apr 26, 2011, 7:45 PM EDT
In force
54 min
Issued by
the Storm Prediction Center
All 62 counties

Allegany County, NY, Broome County, NY, Cayuga County, NY, Chemung County, NY, Chenango County, NY, Cortland County, NY, Delaware County, NY, Fulton County, NY, Hamilton County, NY, Herkimer County, NY, Lewis County, NY, Livingston County, NY, Madison County, NY, Montgomery County, NY, Oneida County, NY, Onondaga County, NY, Ontario County, NY, Oswego County, NY, Otsego County, NY, Schuyler County, NY, Seneca County, NY, Steuben County, NY, Tioga County, NY, Tompkins County, NY, Warren County, NY, Wayne County, NY, Yates County, NY, Adams County, PA, Bedford County, PA, Blair County, PA, Bradford County, PA, Cambria County, PA, Cameron County, PA, Centre County, PA, Clearfield County, PA, Clinton County, PA, Columbia County, PA, Cumberland County, PA, Dauphin County, PA, Elk County, PA, Franklin County, PA, Fulton County, PA, Huntingdon County, PA, Indiana County, PA, Jefferson County, PA, Juniata County, PA, Lackawanna County, PA, Luzerne County, PA, Lycoming County, PA, McKean County, PA, Mifflin County, PA, Montour County, PA, Northumberland County, PA, Perry County, PA, Potter County, PA, Snyder County, PA, Somerset County, PA, Sullivan County, PA, Susquehanna County, PA, Tioga County, PA, Union County, PA, Wyoming County, PA

The radar

The State College radar (KCCX), 65 km from the middle of the area, began a volume at 22:52 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, 10.9 hours before the alert went out and 205 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, Buffalo Intl Airport, NY at 12:00Z on 2011-04-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Buffalo Intl Airport, NY at 12:00Z on 2011-04-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 128 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
493 m above ground
0-6 km bulk shear
57 kt
0-1 km storm-relative helicity
128 m²/s²
0-3 km storm-relative helicity
237 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

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
Apr 26, 1:18 PM EDTMesoscale DiscussionSPCAllegany, Broome, Cattaraugus, Cayuga, Chemung, Chenango and 14 more57 min
Apr 26, 1:49 PM EDTSevere Thunderstorm WatchSPCAllegany, Broome, Cattaraugus, Cayuga, Chemung, Chenango and 26 more7 hr
Apr 26, 4:12 PM EDTMesoscale DiscussionSPCAlbany, Broome, Chemung, Chenango, Cortland, Delaware and 22 more63 min

Nearby

Mesoscale Discussions in Pennsylvania, 2011Mesoscale Discussions in New York, 2011Every mesoscale discussion in 2011

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.