Alert archive / Pennsylvania / Mesoscale Discussions in 2016

Mesoscale Discussion 875

June 11, 20165 states

The Storm Prediction Center issued this mesoscale discussion at Jun 11, 2016, 2:32 PM EDT for 5 states. It was in force for 58 min.

The area

The outline as issued.

The facts

Issued
Jun 11, 2016, 2:32 PM EDT (18:32 UTC)
Expired
Jun 11, 2016, 3:30 PM EDT
In force
58 min
Issued by
the Storm Prediction Center
Chance of a watch
60%
All 82 counties

Bergen County, NJ, Essex County, NJ, Hunterdon County, NJ, Mercer County, NJ, Morris County, NJ, Passaic County, NJ, Somerset County, NJ, Sussex County, NJ, Union County, NJ, Warren County, NJ, Columbia County, NY, Delaware County, NY, Dutchess County, NY, Greene County, NY, Orange County, NY, Putnam County, NY, Rockland County, NY, Schoharie County, NY, Sullivan County, NY, Ulster County, NY, Belmont County, OH, Carroll County, OH, Columbiana County, OH, Harrison County, OH, Holmes County, OH, Jefferson County, OH, Mahoning County, OH, Stark County, OH, Summit County, OH, Tuscarawas County, OH, Wayne County, OH, Adams County, PA, Allegheny County, PA, Armstrong County, PA, Beaver County, PA, Bedford County, PA, Berks County, PA, Blair County, PA, Bucks County, PA, Butler County, PA, Cambria County, PA, Carbon County, PA, Centre County, PA, Chester County, PA, Clearfield County, PA, Columbia County, PA, Cumberland County, PA, Dauphin County, PA, Delaware County, PA, Fayette County, PA, Franklin County, PA, Fulton County, PA, Greene County, PA, Huntingdon County, PA, Indiana County, PA, Juniata County, PA, Lackawanna County, PA, Lancaster County, PA, Lawrence County, PA, Lebanon County, PA, Lehigh County, PA, Luzerne 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, Somerset County, PA, Union County, PA, Washington County, PA, Wayne County, PA, Westmoreland County, PA, York County, PA, Brooke County, WV, Hancock County, WV, Ohio County, WV

The radar

The State College radar (KCCX), 32 km from the middle of the area, began a volume at 18:32 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

Pittsburgh, PA (KAGC), launched 12:00Z, 6.5 hours before the alert went out and 218 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 2016-06-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 32 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 2016-06-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 257 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
32 J/kg
Mixed-layer CIN
-155 J/kg
Mixed-layer LCL
1321 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
257 m²/s²
0-3 km storm-relative helicity
268 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

279 
ACUS11 KWNS 111832
SWOMCD
SPC MCD 111832 
CTZ000-MAZ000-NYZ000-NJZ000-PAZ000-MDZ000-WVZ000-OHZ000-111930-

MESOSCALE DISCUSSION 0875
NWS STORM PREDICTION CENTER NORMAN OK
0132 PM CDT SAT JUN 11 2016

AREAS AFFECTED...PA...NJ...SE NY

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 111832Z - 111930Z

PROBABILITY OF WATCH ISSUANCE...60 PERCENT

SUMMARY...A POTENTIAL FOR WIND DAMAGE AND HAIL IS EXPECTED TO
DEVELOP THIS AFTERNOON FROM ERN OH ACROSS SRN AND CNTRL PA INTO NRN
NJ AND SE NY. WW ISSUANCE MAY BE NEEDED OVER THE NEXT HOUR OR TWO AS
STORMS INITIATE AND CONVECTIVE COVERAGE INCREASES WITH THE MOST
LIKELY LOCATION OF THE WATCH ACROSS ERN OH INTO SRN PA.

DISCUSSION...LATEST SFC ANALYSIS SHOWS A SFC TROUGH EXTENDING SEWD
ACROSS CNTRL NY INTO NRN NJ WITH A MOIST AIRMASS TO THE WEST OF THE
SFC TROUGH. SFC WINDS ARE WESTERLY ACROSS MUCH OF PA INTO ERN OH
WITH SFC DEWPOINTS IN THE LOWER TO MID 60S F. AS SFC TEMPS CONTINUE
TO WARM INTO THE UPPER 80S AND LOWER 90S F...A CORRIDOR OF MODERATE
INSTABILITY IS EXPECTED TO DEVELOP. ON THE NRN EDGE OF
INSTABILITY...VISIBLE SATELLITE IMAGERY SHOWS A FIELD OF CUMULUS
PRESENT NEAR AND TO THE WEST OF STATE COLLEGE EXTENDING INTO NE OH
WITH RADAR SHOWING SEVERAL NEW ECHOES OVER CNTRL PA AND NRN OH. THE
LATEST ESRL HRRR TAKES THIS CONVECTION AND DEVELOPS SEVERAL
THUNDERSTORMS OVER THE NEXT HOUR OR TWO WITH THIS ACTIVITY MOVING
SEWD ACROSS ERN OH AND SRN PA BY LATE THIS AFTERNOON. OTHER STORMS
MAY DEVELOP IN SE NY ALONG THE AXIS OF STRONGEST LOW-LEVEL FLOW. THE
LATEST WSR-88D VWPS ALONG THE MCD CORRIDOR INCLUDING THE PITTSBURGH
18Z SOUNDING SHOW UNIDIRECTIONAL WLY LOW TO MID-LEVEL FLOW WITH
SUBSTANTIAL SPEED SHEAR IN THE LOWEST 3 KM. THIS ALONG WITH
STEEPENING LOW-LEVEL LAPSE RATES SHOULD SUPPORT A WIND DAMAGE THREAT
WITH THE BETTER ORGANIZED MULTICELLS. HAIL COULD ALSO OCCUR WITH THE
STRONGER UPDRAFTS.

..BROYLES/WEISS.. 06/11/2016

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...OKX...ALY...PHI...BGM...CTP...LWX...PBZ...CLE...

LAT...LON   39778007 39948122 40438211 40968207 41148163 41058031
            41037866 41057633 42317526 42617478 42687444 42517378
            42117342 41367370 40057478 39707620 39727871 39778007

Nearby

Mesoscale Discussions in Pennsylvania, 2016Mesoscale Discussions in Ohio, 2016Mesoscale Discussions in New Jersey, 2016Every mesoscale discussion in 2016

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.