Alert archive / West Virginia / Mesoscale Discussions in 2012

Mesoscale Discussion 283

March 19, 201213 counties in Ohio; 4 counties in Virginia; 32 counties in West Virginia

The Storm Prediction Center issued this mesoscale discussion at Mar 19, 2012, 3:42 AM EDT for 13 counties in Ohio; 4 counties in Virginia; 32 counties in West Virginia. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued: Mar 19, 2012, 3:42 AM EDT (07:42 UTC)
Expired: Mar 19, 2012, 5:15 AM EDT
In force: 93 min
Issued by: the Storm Prediction Center

All 49 counties

Athens County, OH, Gallia County, OH, Guernsey County, OH, Hocking County, OH, Jackson County, OH, Meigs County, OH, Monroe County, OH, Morgan County, OH, Muskingum County, OH, Noble County, OH, Perry County, OH, Vinton County, OH, Washington County, OH, Alleghany County, VA, Bath County, VA, City of Covington, VA, Highland County, VA, Barbour County, WV, Boone County, WV, Braxton County, WV, Cabell County, WV, Calhoun County, WV, Clay County, WV, Doddridge County, WV, Fayette County, WV, Gilmer County, WV, Greenbrier County, WV, Harrison County, WV, Jackson County, WV, Kanawha County, WV, Lewis County, WV, Lincoln County, WV, Mason County, WV, Monroe County, WV, Nicholas County, WV, Pleasants County, WV, Pocahontas County, WV, Putnam County, WV, Raleigh County, WV, Randolph County, WV, Ritchie County, WV, Roane County, WV, Summers County, WV, Tyler County, WV, Upshur County, WV, Webster County, WV, Wetzel County, WV, Wirt County, WV, Wood County, WV

The radar

The Charleston,WV radar (KRLX), 73 km from the middle of the area, began a volume at 07:42 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 00:00Z, 7.7 hours before the alert went out and 199 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: 89 J/kg
Mixed-layer CIN: -38 J/kg
Mixed-layer LCL: 1241 m above ground
0-6 km bulk shear: 17 kt
0-1 km storm-relative helicity: 68 m²/s²
0-3 km storm-relative helicity: 63 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.

671 
ACUS11 KWNS 190743
SWOMCD
SPC MCD 190742
VAZ000-WVZ000-OHZ000-190915-

MESOSCALE DISCUSSION 0283
NWS STORM PREDICTION CENTER NORMAN OK
0242 AM CDT MON MAR 19 2012

AREAS AFFECTED...PARTS OF SE OH INTO W WV

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY

VALID 190742Z - 190915Z

WHILE A WEAK UPPER TROUGH CONTINUES TO SLOWLY DIG SOUTHEASTWARD INTO
THE NORTH CENTRAL APPALACHIANS...LOWER/MID TROPOSPHERIC WARM
ADVECTION IN ITS WAKE HAS BEEN CONTRIBUTING TO SCATTERED VIGOROUS
THUNDERSTORM ACTIVITY ACROSS SOUTHEASTERN OHIO INTO WEST VIRGINIA
DURING THE PAST FEW HOURS.  THIS IS ON THE BROAD EASTERN FRINGE OF
WARM ELEVATED MIXED LAYER AIR WHICH HAS SHIFTED EAST OF THE
PLAINS...AND IS CONTRIBUTING FAVORABLE THERMODYNAMIC PROFILES FOR
HAIL APPROACHING OR BRIEFLY EXCEEDING SEVERE LIMITS IN STRONGER
UPDRAFT PULSES.  SHEAR BENEATH MODEST NORTHWESTERLY MID-LEVEL FLOW
IS NOT PARTICULARLY STRONG...AND FORCING IS NOT EXPECTED TO SUPPORT
FURTHER UPSCALE CONVECTIVE GROWTH BEFORE IT BEGINS TO WEAKEN IN THE
10-12Z TIME FRAME.  IT IS NOT ENTIRELY OUT OF THE QUESTION THAT SOME
THUNDERSTORM ACTIVITY COULD CONTINUE ACROSS PARTS OF THE UPPER OHIO
VALLEY INTO THE NORTH CENTRAL APPALACHIANS BEYOND DAYBREAK...BUT
CONVECTION ATTEMPTING TO CROSS TO THE LEE OF THE HIGHER TERRAIN IS
EXPECTED TO WEAKEN.

..KERR.. 03/19/2012

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

ATTN...WFO...LWX...RNK...PBZ...RLX...ILN...

LAT...LON   40028250 40148149 39688056 38807944 38187932 37508009
            37468075 37818174 38638251 39158286 40028250

Nearby

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