SPC MD 2178

MD 2178 CONCERNING BLIZZARD FOR NWRN AND N-CNTRL KS / S-CNTRL NEB


MESOSCALE DISCUSSION 2178
NWS STORM PREDICTION CENTER NORMAN OK
0619 PM CST WED DEC 19 2012

AREAS AFFECTED...NWRN AND N-CNTRL KS / S-CNTRL NEB

CONCERNING...BLIZZARD

VALID 200019Z - 200415Z

SUMMARY...A CESSATION OF THE HEAVIEST SNOWFALL RATES IS EXPECTED TO
OCCUR FIRST OVER NWRN KS AND ADJACENT PARTS OF SWRN NEB DURING THE
00-03 UTC PERIOD WITH SNOWFALL RATES ABATING SUBSTANTIALLY DURING
THE 03-06 UTC PERIOD FARTHER E OVER MAINLY S-CNTRL NEB AND FAR
N-CNTRL KS.  BLIZZARD CONDITIONS SHOULD CONTINUE INTO THE EVENING
HOURS ACROSS THE DISCUSSION AREA...OWING TO REDUCED VISIBILITIES AND
FREQUENT WIND GUSTS AOA 35 MPH.

DISCUSSION...SURFACE MESOANALYSIS PLACES A 996MB LOW ALONG THE OK/KS
BORDER 40 MI SSW ICT.  AS THE UPPER TROUGH AND ASSOCIATED DEEP LAYER
FORCING FOR ASCENT PIVOT EWD FROM NEAR THE CO/KS/OK BORDER TO
E-CNTRL KS BY 06 UTC...THE DEEPENING/DEVELOPMENT OF THE DEEP LAYER
CYCLONE WILL OCCUR FROM NEAR ITS CURRENT POSITION ALONG THE KS/OK
BORDER NEWD TO NWRN MO/NERN KS BY 06 UTC.  AS THIS OCCURS...EXPECT
THE HEAVIEST SNOWFALL RATES TO RESIDE FROM NWRN KS /0.50-LOCALLY 1
INCH PER HR FROM 00-02 UTC/ TO S-CNTRL NEB /1-1.5 INCH PER HR FROM
00-06 UTC/ AND CORRESPONDINGLY ABATING IN A GRADUAL MANNER IN A
GENERAL WSW-ENE DIRECTION.  IN THE MEANTIME...THE HEAVIEST SNOWFALL
RATES WILL LIKELY EXIST DURING THE NEXT FEW HOURS IN THE HSI-LNK
CORRIDOR WHERE A REDUCTION IN STATIC STABILITY IS GREATEST IN
ASSOCIATION WITH A MID-LEVEL DRY SLOT IMPINGING TO THE S IN NERN KS.
 IT IS WITHIN THIS CORRIDOR THAT ISOLD LIGHTNING STRIKES HAVE BEEN
DETECTED...SIGNALING WHERE CONVECTIVE ENHANCEMENT MAY LOCALLY
INCREASE SNOWFALL RATES.  BRISK NLY WIND GUSTS FREQUENTLY AOA 35MPH
AND LOW VISIBILITIES WILL OCCUR THROUGH THE EVENING /ESPECIALLY IN
THE HEAVIEST SNOW BURSTS/.

..SMITH.. 12/20/2012

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

ATTN...WFO...OAX...GID...LBF...GLD...

LAT...LON   39730134 40919927 41299782 41079706 40449686 40149746
            39759912 39140112 39730134

via SPC Forecast Products http://www.spc.noaa.gov/products/md/md2178.html