SPC MD 1753

MD 1753 CONCERNING SEVERE POTENTIAL…WATCH LIKELY FOR PORTIONS OF KANSAS AND SOUTHERN NEBRASKA

MESOSCALE DISCUSSION 1753
NWS STORM PREDICTION CENTER NORMAN OK
0151 PM CDT TUE OCT 04 2016

AREAS AFFECTED...PORTIONS OF KANSAS AND SOUTHERN NEBRASKA

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 

VALID 041851Z - 042015Z

PROBABILITY OF WATCH ISSUANCE...95 PERCENT

SUMMARY...THUNDERSTORMS SHOULD GRADUALLY INCREASE IN COVERAGE ACROSS
CENTRAL KANSAS AND SOUTH-CENTRAL NEBRASKA LATER THIS
AFTERNOON...BEFORE SPREADING EAST THIS EVENING. THE PRIMARY THREATS
WILL LIKELY BE LARGE HAIL AND DAMAGING WINDS...BUT A COUPLE
TORNADOES MAY BE POSSIBLE AS WELL...GENERALLY PRIOR TO SUNSET. WATCH
ISSUANCE IS LIKELY WITHIN THE NEXT HOUR OR SO.

DISCUSSION...WATER-VAPOR IMAGERY CLEARLY DEPICTS A SHORTWAVE TROUGH
PUSHING INTO WESTERN KS THIS AFTERNOON. AS THIS IMPULSE REACHES
CENTRAL KANSAS...SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP
ALONG A SURFACE TROUGH WEST OF THE I-35/135 CORRIDOR...AS WELL AS
FARTHER NORTH INTO SOUTH-CENTRAL NEBRASKA.  

IN COMBINATION WITH IMPROVING BOUNDARY-LAYER MOISTURE...SFC HEATING
BEHIND EARLIER CONVECTION IS SUPPORTING MLCAPE VALUES UPWARDS OF
1000-1500 J/KG...AND POCKETS UPWARDS OF 2000 J/KG MAY MATERIALIZE BY
LATE AFTERNOON. IN ADDITION TO MODEST DIRECTIONAL SHEAR...VIGOROUS
MID-LEVEL SOUTH/SOUTHWESTERLIES AROUND 45-55 KTS ARE SUPPORTING
AMPLE DEEP SHEAR FOR UPDRAFT ORGANIZATION/ROTATION TODAY. AS
SUCH...WHILE INSTABILITY IS NOT PARTICULARLY ROBUST...FAIRLY
EFFICIENT HAIL GROWTH SHOULD LEAD TO SEVERAL LARGE-HAIL REPORTS.
ADDITIONALLY...SUFFICIENT LOW-LEVEL SHEAR AND INITIALLY DISCRETE
SUPERCELLULAR DEVELOPMENT MAY ENCOURAGE A COUPLE OF TORNADOES DURING
THE LATE AFTERNOON AND EARLY EVENING HOURS. THEREAFTER...STORM
SPLITS/DOWNSTREAM ANVIL SEEDING FROM A RELATIVELY UNIDIRECTIONAL
WIND PROFILE WILL LIKELY FAVOR UPSCALE GROWTH...LOWERING THE TORNADO
THREAT AND ENHANCING THE WIND THREAT WITH EASTWARD EXTENT.

REGARDLESS...CONSIDERING THE INCREASING THREAT FOR ALL SEVERE MODES
THIS AFTERNOON...WATCH ISSUANCE IS LIKELY WITHIN THE NEXT HOUR OR
SO.

..PICCA/HART.. 10/04/2016

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

ATTN...WFO...OAX...TOP...ICT...GID...DDC...

LAT...LON   37089886 37949886 40289827 40449821 40569802 40639738
            40569670 40369595 40009571 38949603 38499629 37199698
            37089748 37089766 37089886 

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