Alert archive / West Virginia / Mesoscale Discussions in 2012

Mesoscale Discussion 372

March 28, 20125 states

The Storm Prediction Center issued this mesoscale discussion at Mar 28, 2012, 12:43 PM EDT for 5 states. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Mar 28, 2012, 12:43 PM EDT (16:43 UTC)
Expired
Mar 28, 2012, 2:45 PM EDT
In force
2 hr
Issued by
the Storm Prediction Center
All 77 counties

Bath County, KY, Boyd County, KY, Breathitt County, KY, Carter County, KY, Elliott County, KY, Fleming County, KY, Floyd County, KY, Greenup County, KY, Johnson County, KY, Knott County, KY, Lawrence County, KY, Lee County, KY, Lewis County, KY, Magoffin County, KY, Martin County, KY, Mason County, KY, Menifee County, KY, Morgan County, KY, Pike County, KY, Powell County, KY, Rowan County, KY, Wolfe County, KY, Allegany County, MD, Garrett County, MD, Gallia County, OH, Jackson County, OH, Lawrence County, OH, Meigs County, OH, Scioto County, OH, Bath County, VA, Frederick County, VA, Highland County, VA, Shenandoah 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, Grant County, WV, Greenbrier County, WV, Hampshire County, WV, Hardy County, WV, Harrison County, WV, Jackson County, WV, Kanawha County, WV, Lewis County, WV, Lincoln County, WV, Logan County, WV, Marion County, WV, Mason County, WV, Mineral County, WV, Mingo County, WV, Monongalia County, WV, Nicholas County, WV, Pendleton County, WV, Pleasants County, WV, Pocahontas County, WV, Preston County, WV, Putnam County, WV, Raleigh County, WV, Randolph County, WV, Ritchie County, WV, Roane County, WV, Taylor County, WV, Tucker County, WV, Tyler County, WV, Upshur County, WV, Wayne County, WV, Webster County, WV, Wetzel County, WV, Wirt County, WV, Wood County, WV, Wyoming County, WV

The radar

The Charleston,WV radar (KRLX), 93 km from the middle of the area, began a volume at 16:45 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

Roanoke, VA (KRNK), launched 12:00Z, 4.7 hours before the alert went out and 198 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, Roanoke, VA at 12:00Z on 2012-03-28Temperature 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, Roanoke, VA at 12:00Z on 2012-03-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 296 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
1288 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
296 m²/s²
0-3 km storm-relative helicity
269 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.

564 
ACUS11 KWNS 281643
SWOMCD
SPC MCD 281643 
VAZ000-WVZ000-MDZ000-PAZ000-OHZ000-KYZ000-281845-

MESOSCALE DISCUSSION 0372
NWS STORM PREDICTION CENTER NORMAN OK
1143 AM CDT WED MAR 28 2012

AREAS AFFECTED...FAR SOUTHERN OH/EASTERN KY AND MUCH OF WV AND
ADJACENT VA/MD

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 

VALID 281643Z - 281845Z

A SEVERE THREAT IS EXPECTED TO STEADILY INCREASE THROUGH EARLY/MID
AFTERNOON ACROSS PORTIONS OF FAR SOUTHERN OH AND ESPECIALLY INTO
EASTERN KY/MUCH OF WV AND ADJACENT PARTS OF VA/MD. A WATCH WILL
LIKELY BE NECESSARY FOR MUCH OF THIS REGION THIS AFTERNOON.

ELEVATED STRONG/SOME MARGINALLY SEVERE TSTMS WITH HAIL CONTINUE TO
OCCUR NEAR THE OH/WV/PA BORDER REGION EARLY THIS AFTERNOON...AND
THESE STORMS MAY BECOME MORE SURFACE BASED OVER THE NEXT COUPLE OF
HOURS AS THE BOUNDARY LAYER CONTINUES TO WARM. FARTHER
SOUTHWEST...ADDITIONAL SURFACE BASED DEVELOPMENT SHOULD OCCUR ACROSS
PORTIONS OF FAR SOUTHERN OH INTO EASTERN KY/MUCH OF WV THIS
AFTERNOON. IN THIS CORRIDOR...CINH CONTINUES TO QUICKLY ERODE
THROUGH MIXING...WITH MOIST ADVECTION ALSO OCCURRING VIA THE
EASTWARD ADVECTION OF A RELATIVELY HIGHER MOIST PLUME ALONG THE
LOWER OH RIVER PER GPS/SATELLITE DERIVED PW. ACCORDINGLY...RECENT
VISIBLE SATELLITE IMAGERY IS INDICATIVE OF AN INCREASE IN BOUNDARY
LAYER CUMULUS ACROSS EASTERN KY TO CENTRAL WV TO THE SOUTHEAST OF
THE COLD FRONT/ZONE OF CONFLUENCE.

GIVEN THIS SCENARIO...RELATIVELY HIGH CONFIDENCE EXISTS IN AN
AFTERNOON UPSWING OF SURFACE BASED TSTM COVERAGE AND INTENSITY. EVEN
WITH MODEST BOUNDARY LAYER MOISTURE /GENERALLY 50S F SFC
DEWPOINTS/...ADDITIONAL HEATING/MOIST ADVECTION OVER THE NEXT FEW
HOURS WILL ALLOW FOR MLCAPES TO REACH 1000+ J/KG ESPECIALLY
ALONG/WEST OF THE APPALACHIANS SPINE. WITH THE REGION ON THE
SOUTHERN PERIPHERY OF STRONG WESTERLY FLOW ALOFT...STRONG/NEARLY
UNIDIRECTIONAL LOW/MID TROPOSPHERIC FLOW WILL ALLOW FOR SOME
SPLITTING SUPERCELLS WITH EAST-SOUTHEASTWARD MOVING LINE SEGMENTS
OTHERWISE MORE COMMON. DAMAGING WINDS/SEVERE HAIL WILL BE THE
PRIMARY HAZARDS.

..GUYER.. 03/28/2012

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

ATTN...WFO...CTP...LWX...RNK...PBZ...RLX...JKL...ILN...LMK...

LAT...LON   39027827 37987972 37278273 37608387 38598384 39248237
            39857960 39537823 39027827

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 28, 2:06 PM EDTSevere Thunderstorm WatchSPCAnderson, Bath, Bourbon, Boyd, Boyle, Bracken and 64 more7 hr
Mar 28, 4:37 PM EDTMesoscale DiscussionSPCAdair, Anderson, Bath, Bourbon, Boyd, Boyle and 53 more113 min
Mar 28, 10:23 AM EDTMesoscale DiscussionSPCAllegany, Frederick, Garrett, Montgomery, Washington2 hr

Nearby

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