Alert archive / West Virginia / Mesoscale Discussions in 2012

Mesoscale Discussion 2230

December 26, 2012Athens County, Washington County, Ohio; 15 counties in West Virginia

The Storm Prediction Center issued this mesoscale discussion at Dec 26, 2012, 6:46 AM EST for Athens County, Washington County, Ohio; 15 counties in West Virginia. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued: Dec 26, 2012, 6:46 AM EST (11:46 UTC)
Expired: Dec 26, 2012, 10:45 AM EST
In force: 4 hr
Issued by: the Storm Prediction Center

Counties Athens County, OH, Washington County, OH, Barbour County, WV, Doddridge County, WV, Fayette County, WV, Greenbrier County, WV, Harrison County, WV, Nicholas County, WV, Pleasants County, WV, Pocahontas County, WV, Randolph County, WV, Summers County, WV, Taylor County, WV, Tyler County, WV, Upshur County, WV, Webster County, WV, Wetzel County, WV

The radar

The Charleston,WV radar (KRLX), 90 km from the middle of the area, began a volume at 11:46 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, 11.8 hours before the alert went out and 190 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: 793 m above ground
0-6 km bulk shear: 36 kt
0-1 km storm-relative helicity: -28 m²/s²
0-3 km storm-relative helicity: 95 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.

137 
ACUS11 KWNS 261146
SWOMCD
SPC MCD 261146 
WVZ000-OHZ000-261545-

MESOSCALE DISCUSSION 2230
NWS STORM PREDICTION CENTER NORMAN OK
0546 AM CST WED DEC 26 2012

AREAS AFFECTED...PORTIONS OF  CNTRL/WRN WV AND SE OH

CONCERNING...FREEZING RAIN 

VALID 261146Z - 261545Z

SUMMARY...RAIN CHANGING TO FREEZING RAIN IS EXPECTED BY 13Z.
FREEZING RAIN WITH RATES OF 0.05-0.10 INCHES ARE POSSIBLE THROUGH
MIDDAY...ESPECIALLY OVER HIGHER ELEVATIONS IN EASTERN PORTIONS OF
THE MCD AREA.

DISCUSSION...11Z OBSERVATIONS INDICATED SFC TEMPERATURES FALLING TO
NEAR FREEZING WITH LIGHT RAIN. OVER THE NEXT HOUR OR TWO...A
TRANSITION TO MORE WIDESPREAD FREEZING RAIN IS EXPECTED.
WARM...MOIST AIR WRAPPING AROUND APPROACHING SFC LOW /LOCATED OVER
NE TN AT 11Z/ WILL OVERSPREAD THE SHALLOW NEAR-SURFACE COLD LAYER.
PVA AHEAD OF UPPER SHORTWAVE TROUGH AND BAND OF 850-700 MB
FRONTOGENESIS WILL PROVIDE FORCING FOR ASCENT THROUGH DEEP SATURATED
MIDLEVELS. THIS WILL LEAD TO PERIOD OF LIGHT TO MODERATE FREEZING
RAIN. RATES OF 0.05-0.10 INCH PER HOUR WILL BE POSSIBLE AT TIMES
THROUGH MIDDAY.

..LEITMAN.. 12/26/2012

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

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

LAT...LON   37588084 37658115 37808128 38058118 38388076 38568053
            38828034 38928040 39098054 39378101 39358141 39188186
            39188230 39348234 39528214 39628174 39678116 39608062
            39528029 39417999 39087968 38817948 37718029 37588084

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Dec 26, 3:25 AM EST	Mesoscale Discussion	SPC	Auglaize, Butler, Champaign, Clark, Darke, Greene and 9 more	6 hr
Dec 26, 9:57 AM EST	Mesoscale Discussion	SPC	Coshocton, Delaware, Fairfield, Fayette, Franklin, Guernsey and 8 more	5 hr
Dec 26, 10:39 AM EST	Mesoscale Discussion	SPC	Allen, Auglaize, Champaign, Crawford, Darke, Defiance and 21 more	6 hr
Dec 26, 11:40 AM EST	Mesoscale Discussion	SPC	Ashland, Carroll, Columbiana, Geauga, Holmes, Mahoning and 8 more	6 hr
Dec 26, 12:48 PM EST	Mesoscale Discussion	SPC	Berkeley, Grant, Hampshire, Hardy, Jefferson, Mineral and 5 more	6 hr

Nearby

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