Alert archive / Ohio / Mesoscale Discussions in 2012

Mesoscale Discussion 1352

July 1, 20124 counties in Kentucky; 41 counties in Ohio; 15 counties in West Virginia

The Storm Prediction Center issued this mesoscale discussion at Jul 1, 2012, 8:21 PM EDT for 4 counties in Kentucky; 41 counties in Ohio; 15 counties in West Virginia. It was in force for 54 min.

The area

The outline as issued.

The facts

Issued
Jul 1, 2012, 8:21 PM EDT (00:21 UTC)
Expired
Jul 1, 2012, 9:15 PM EDT
In force
54 min
Issued by
the Storm Prediction Center
All 60 counties

Boyd County, KY, Carter County, KY, Greenup County, KY, Lawrence County, KY, Ashland County, OH, Athens County, OH, Belmont County, OH, Carroll County, OH, Columbiana County, OH, Coshocton County, OH, Cuyahoga County, OH, Delaware County, OH, Fairfield County, OH, Franklin County, OH, Gallia County, OH, Geauga County, OH, Guernsey County, OH, Harrison County, OH, Hocking County, OH, Holmes County, OH, Jackson County, OH, Jefferson County, OH, Knox County, OH, Lawrence County, OH, Licking County, OH, Medina County, OH, Meigs County, OH, Monroe County, OH, Morgan County, OH, Morrow County, OH, Muskingum County, OH, Noble County, OH, Perry County, OH, Pickaway County, OH, Pike County, OH, Portage County, OH, Richland County, OH, Ross County, OH, Scioto County, OH, Stark County, OH, Summit County, OH, Tuscarawas County, OH, Vinton County, OH, Washington County, OH, Wayne County, OH, Boone County, WV, Cabell County, WV, Calhoun County, WV, Jackson County, WV, Kanawha County, WV, Lincoln County, WV, Mason County, WV, Pleasants County, WV, Putnam County, WV, Ritchie County, WV, Roane County, WV, Tyler County, WV, Wayne County, WV, Wirt County, WV, Wood County, WV

The radar

The Pittsburgh radar (KPBZ), 149 km from the middle of the area, began a volume at 00:21 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 (KPIT), launched 00:00Z, 0.4 hours before the alert went out and 154 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 00:00Z on 2012-07-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 334 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 00:00Z on 2012-07-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 12 square meters per square second.1939587897Sfc1 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
334 J/kg
Mixed-layer CIN
-71 J/kg
Mixed-layer LCL
2439 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
12 m²/s²
0-3 km storm-relative helicity
139 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.1

Open this sounding in Storm Lab

The text

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

473 
ACUS11 KWNS 020021
SWOMCD
SPC MCD 020021 
WVZ000-OHZ000-KYZ000-020115-

MESOSCALE DISCUSSION 1352
NWS STORM PREDICTION CENTER NORMAN OK
0721 PM CDT SUN JUL 01 2012

AREAS AFFECTED...CNTRL/ERN OH...CNTRL/WRN WV...NERN KY

CONCERNING...SEVERE THUNDERSTORM WATCH 446...447...

VALID 020021Z - 020115Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH
446...447...CONTINUES.

SUMMARY...THE THREAT FOR SVR WINDS WILL CROSS ERN/SRN OH INTO
CNTRL/WRN WV AND NERN KY DURING THE NEXT FEW HOURS. THE GREATEST
COVERAGE OF DMGG WINDS IS EXPECTED ACROSS SERN OH INTO WRN/CNTRL WV
AS STORMS CROSS THE OHIO RIVER SHORTLY.

DISCUSSION...CONVECTION CONTINUES TO INTENSIFY ALONG THE LEADING
EDGE OF A STRONG COLD POOL FEATURING 2-HRLY PRESSURE RISES OF AROUND
2-3.5 MB WITHIN THE WILMINGTON-COLUMBUS-MANSFIELD-CLEVELAND
CORRIDOR. AN ORGANIZING LEADING-LINE/TRAILING-STRATIFORM QUASILINEAR
CONVECTIVE SYSTEM /QLCS/ APPEARS TO BE DEVELOPING...EXTENDING FROM
NEAR CLEVELAND TO ZANESVILLE ARCING SWWD TOWARD PORTSMOUTH.

THE SEGMENT OF THIS QLCS SOUTH OF INTERSTATE 70 WILL POSE THE
GREATEST THREAT FOR WIDESPREAD DMGG WIND GUSTS AS IT CROSSES THE
OHIO RIVER...APPROACHING THE CHARLESTON AREA WITHIN THE 0200-0300Z
TIME FRAME. AN ABUNDANCE OF SVR WIND REPORTS...INCLUDED MEASURED SVR
GUSTS...HAVE OCCURRED ACROSS CNTRL OH WITH THIS LINE OF STORMS.
AND...AS IT ENCOUNTERS A ZONE OF 2000-3500 J/KG MLCAPE DOWNSTREAM
AMIDST 30-40 KT OF EFFECTIVE BULK SHEAR...FORWARD PROPAGATION WILL
CONTINUE.

FARTHER NORTH...INSTABILITY IS SOMEWHAT LOWER NORTH OF A DIFFUSE
STATIONARY FRONT...WHICH MAY MITIGATE THE COVERAGE OF SVR WIND GUSTS
TO SOME DEGREE. REGARDLESS...COLD POOL/SHEAR INTERACTIONS WILL
SUPPORT CONTINUED SVR POTENTIAL.

WW/S 446 AND 447 HAVE BEEN EXPANDED EWD UPON COORDINATION WITH
AFFECTED WEATHER FORECAST OFFICES. COUNTIES MAY BE CLEARED FROM THE
WW/S FOLLOWING PASSAGE OF THE CONVECTIVE LINE.

..COHEN.. 07/02/2012

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

ATTN...WFO...PBZ...RLX...CLE...JKL...ILN...

LAT...LON   41718107 40728069 39228078 37868147 37928277 38968355
            40598312 41508204 41718107

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 1, 8:32 PM EDTMesoscale DiscussionSPCFloyd, Knott, Leslie, Letcher, Magoffin, Perry and 1 more88 min
Jul 1, 9:02 PM EDTMesoscale DiscussionSPCAnderson, Boone, Bourbon, Boyle, Bracken, Breckinridge and 33 more58 min
Jul 1, 9:06 PM EDTSevere Thunderstorm WatchSPCBreathitt, Estill, Floyd, Harlan, Knott, Lee and 5 more5 hr
Jul 1, 10:26 PM EDTMesoscale DiscussionSPCAdair, Anderson, Bath, Bourbon, Boyd, Boyle and 46 more94 min
Jul 2, 6:16 PM EDTMesoscale DiscussionSPCAdair, Allen, Ballard, Barren, Breckinridge, Bullitt and 40 more2 hr
Jul 2, 12:39 AM EDTMesoscale DiscussionSPCJefferson96 min

Nearby

Mesoscale Discussions in Ohio, 2012Mesoscale Discussions in West Virginia, 2012Mesoscale Discussions in Kentucky, 2012Every 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.