SPC MD 2179

MD 2179 CONCERNING SEVERE POTENTIAL…TORNADO WATCH LIKELY FOR EASTERN OK/NORTHEAST TX/WESTERN AR/FAR SOUTHEAST KS/SOUTHWEST MO


MESOSCALE DISCUSSION 2179
NWS STORM PREDICTION CENTER NORMAN OK
0707 PM CST WED DEC 19 2012

AREAS AFFECTED...EASTERN OK/NORTHEAST TX/WESTERN AR/FAR SOUTHEAST
KS/SOUTHWEST MO

CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY

VALID 200107Z - 200200Z

PROBABILITY OF WATCH ISSUANCE...95 PERCENT

SUMMARY...SEVERE TSTM POTENTIAL IS LIKELY TO QUICKLY INCREASE THIS
EVENING ACROSS PORTIONS OF EASTERN OK/NORTHEAST TX INTO WESTERN AR
ALONG WITH ADJACENT PARTS OF EXTREME SOUTHEAST KS/SOUTHWEST MO. A
TORNADO WATCH WILL LIKELY BE NECESSARY FOR AT LEAST PORTIONS OF THIS
REGION WITHIN THE HOUR /LIKELY BY 02Z/.

DISCUSSION...00Z SURFACE ANALYSIS IS INDICATIVE OF A 996 MB SURFACE
LOW NEAR THE I-35 CORRIDOR OF NORTH-CENTRAL OK/SOUTH-CENTRAL
KS...WITH A STATIONARY FRONT OR SLOW-MOVING MOVING WARM FRONT
EXTENDING EASTWARD ACROSS FAR SOUTHEAST MO...IN ADDITION TO A
SOUTHEASTWARD-MOVING COLD FRONT AND A PRECEDING DRY LINE ACROSS
OK/NORTH-CENTRAL TX. THE ARRIVAL OF CONSEQUENTIAL DPVA/MASS RESPONSE
ASSOCIATED WITH A PLAINS UPPER TROUGH WILL LIKELY CONTRIBUTE TO
INCREASING CONVECTIVE DEVELOPMENT BY THE MID/LATE EVENING
HOURS...ALTHOUGH A RECENT CONVECTIVE INCREASE HAS ALREADY BEEN NOTED
IN LATIMER COUNTY OK PER RADAR IMAGERY AS OF 0115Z...AND MORE
ROBUSTLY IN VICINITY OF A PRE-FRONTAL TROUGH/DRYLINE NEAR THE RED
RIVER OF SOUTH-CENTRAL OK/NORTH-CENTRAL TX.

THE 00Z FORT WORTH OBSERVED SOUNDING WAS INDICATIVE OF RELATIVELY
LITTLE CINH...WITH A RELATIVELY STEEP LAPSE RATES PROFILE AND MLCAPE
AROUND 300 J/KG. SPC OBJECTIVE ANALYSIS OTHERWISE SUGGESTS THAT
LOW-LEVEL CINH EROSION CONTINUES TO OCCUR WITHIN THE WARM SECTOR
WHERE UPPER 50S/LOWER 60S F SURFACE DEWPOINTS ARE INCREASINGLY
PREVALENT.

WITH A PROBABLE INCREASE /QUICK AT THAT/ IN STORM COVERAGE AND
INTENSITY BY MID-EVENING...VERY STRONG DEEP LAYER SOUTHWESTERLY
WINDS ABOVE THE SURFACE AND RESULTANT 70+ KT 0-6 KM SHEAR WILL
SUPPORT A MIXED-MODE OF SUPERCELLS AND THE EVOLUTION OF
SMALL/FAST-NORTHEASTWARD MOVING LINEAR SEGMENTS TONIGHT...WHICH IS
GENERALLY CONSISTENT BY VARIOUS HIGH-RES CONVECTION-ALLOWING
GUIDANCE. WHILE SEVERE HAIL WILL BE POSSIBLE WITHIN THE FIRST FEW
HOURS OF CONVECTIVE INITIATION...DAMAGING WINDS AND THE POSSIBILITY
OF A FEW TORNADOES SHOULD BE THE MORE PREVALENT RISKS.

..GUYER/WEISS.. 12/20/2012

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

ATTN...WFO...LZK...SGF...SHV...TSA...ICT...FWD...OUN...

LAT...LON   36699630 37519556 37699444 37839262 37319172 36009193
            33109389 32179713 33699677 36699630

via SPC Forecast Products http://www.spc.noaa.gov/products/md/md2179.html