Alert archive / Ohio / Mesoscale Discussions in 2012

Mesoscale Discussion 1373

July 3, 201221 counties in Ohio; 10 counties in Pennsylvania; 4 counties in West Virginia

The Storm Prediction Center issued this mesoscale discussion at Jul 3, 2012, 10:20 AM EDT for 21 counties in Ohio; 10 counties in Pennsylvania; 4 counties in West Virginia. It was in force for 85 min.

The area

The outline as issued.

The facts

Issued: Jul 3, 2012, 10:20 AM EDT (14:20 UTC)
Expired: Jul 3, 2012, 11:45 AM EDT
In force: 85 min
Issued by: the Storm Prediction Center
Chance of a watch: 40%

All 35 counties

Ashland County, OH, Belmont County, OH, Carroll County, OH, Columbiana County, OH, Cuyahoga County, OH, Erie County, OH, Geauga County, OH, Harrison County, OH, Holmes County, OH, Huron County, OH, Jefferson County, OH, Lake County, OH, Lorain County, OH, Mahoning County, OH, Medina County, OH, Portage County, OH, Stark County, OH, Summit County, OH, Trumbull County, OH, Tuscarawas County, OH, Wayne County, OH, Allegheny County, PA, Armstrong County, PA, Beaver County, PA, Butler County, PA, Fayette County, PA, Greene County, PA, Lawrence County, PA, Mercer County, PA, Washington County, PA, Westmoreland County, PA, Brooke County, WV, Hancock County, WV, Marshall County, WV, Ohio County, WV

The radar

The Cleveland radar (KCLE), 71 km from the middle of the area, began a volume at 14:23 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 (KPIT), launched 12:00Z, 2.3 hours before the alert went out and 114 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1812 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 48 m²/s²
0-3 km storm-relative helicity: 120 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.

536 
ACUS11 KWNS 031421
SWOMCD
SPC MCD 031420
PAZ000-WVZ000-OHZ000-031545-

MESOSCALE DISCUSSION 1373
NWS STORM PREDICTION CENTER NORMAN OK
0920 AM CDT TUE JUL 03 2012

AREAS AFFECTED...NE OH...NW PA...WV PANHANDLE

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 031420Z - 031545Z

PROBABILITY OF WATCH ISSUANCE...40 PERCENT

SUMMARY...A WIND DAMAGE THREAT WILL MOVE SEWD INTO THE CLEVELAND
AREA AND POSSIBLY ACROSS NE OH LATER THIS MORNING. THE THREAT IS
EXPECTED TO REMAIN TOO ISOLATED TO WARRANT WW ISSUANCE.

DISCUSSION...A SHORT LINE SEGMENT IS CURRENTLY ONGOING AT THE WRN
END OF LAKE ERIE AND IS LOCATED ON THE NRN EDGE OF MODERATE
INSTABILITY. MLCAPE VALUES ARE ESTIMATED TO BE AROUND 1000 J/KG IN
THE VICINITY OF CLEVELAND. IN ADDITION...THE WSR-88D VWP AT
CLEVELAND SHOWS A UNIDIRECTIONAL WIND PROFILE WITH ABOUT 20 KT OF
FLOW AT 1 KM. THIS ALONG WITH STEEPENING LOW-LEVEL LAPSE RATES AS
SFC TEMPS WARM INTO THE MID 80S F ACROSS NE OH WILL LIKELY HELP THE
LINE PRODUCE DAMAGING WIND GUSTS LATE THIS MORNING. THE THREAT IS
EXPECTED TO PERSIST INTO THE EARLY AFTERNOON BUT SHOULD REMAIN
ISOLATED.

..BROYLES/RACY.. 07/03/2012

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

ATTN...WFO...PBZ...CLE...

LAT...LON   41448026 42058174 41978240 41678274 41168275 40588204
            39898086 39627972 40557896 41448026

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 3, 5:58 PM EDT	Mesoscale Discussion	SPC	Athens, Coshocton, Fairfield, Gallia, Guernsey, Hocking and 12 more	3 hr
Jul 3, 7:40 PM EDT	Mesoscale Discussion	SPC	Ashland, Ashtabula, Crawford, Cuyahoga, Erie, Geauga and 14 more	2 hr

Nearby

Mesoscale Discussions in Ohio, 2012 Mesoscale Discussions in Pennsylvania, 2012 Mesoscale Discussions in West Virginia, 2012 Every mesoscale discussion in 2012

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.