000
ACUS11 KWNS 250054
SWOMCD
SPC MCD 250054 COR
NEZ000-KSZ000-COZ000-250215-

MESOSCALE DISCUSSION 0793
NWS STORM PREDICTION CENTER NORMAN OK
0754 PM CDT FRI MAY 24 2013

AREAS AFFECTED...SW NEB...ERN CO...WRN KS

CONCERNING...SEVERE THUNDERSTORM WATCH 215...

VALID 250054Z - 250215Z

CORRECTED FOR WEB GRAPHIC

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 215
CONTINUES.

SUMMARY...PRIMARY SEVERE STORM RISK OF LARGE HAIL WILL PERSIST FROM
NW KS INTO SW NEB FOR THE NEXT FEW HOURS.  AN ISOLATED TORNADO IS
NOT OUT OF THE QUESTION IN THE SOMEWHAT MOISTER ENVIRONMENT ACROSS
SW NEB.

DISCUSSION...SUPERCELLS ARE ONGOING THIS EVENING FROM EXTREME NW KS
INTO SW NEB ALONG THE I-80 CORRIDOR...IMMEDIATELY E-NE OF A DRYLINE
AND SURFACE LOW IN ERN CO.  THE CONVECTION IS BEING SUPPORTED BY THE
INTERACTION OF SUBTLE SPEED MAXIMA ALOFT WITH MODERATE WARM SECTOR
BUOYANCY /MLCAPE NEAR 2000 J PER KG/...IN AN ENVIRONMENT WITH
EFFECTIVE BULK SHEAR OF 35-45 KT.  GIVEN THE STEEP LAPSE RATE
PROFILES AND SUPERCELL STRUCTURES...LARGE HAIL WILL BE THE PRIMARY
SEVERE STORM THREAT.  ADDITIONALLY...THERE WILL BE SOME RISK FOR A
BRIEF TORNADO ACROSS SW NEB IN THE NEXT HOUR OR TWO...PRIMARILY WITH
THE CLUSTER OF STORMS NEAR I-80 THAT RESIDES IN THE ZONE OF STRONGER
LOW-LEVEL SHEAR AND SOMEWHAT LOWER LCL HEIGHTS.  OTHERWISE...STORM
INTERACTIONS SHOULD LEAD TO SOME UPSCALE GROWTH OF A CONVECTIVE
CLUSTER IN NEB...AND POTENTIALLY SOME EWD EXPANSION OF THE SEVERE
THREAT PER THE RECENT ADDITION OF COUNTIES TO THE WATCH IN THE LBF
AREA.

FARTHER S...SURFACE OBSERVATIONS AND VISIBLE SATELLITE IMAGERY
SUGGEST THAT STORM COVERAGE WILL BE SUBSTANTIALLY MORE LIMITED S OF
I-70 IN KS.  LOW-LEVEL ASCENT IS LESS FOCUSED IN SW KS/SE CO  WHERE
THE PRIMARY DRYLINE IS ONLY WEAKLY CONVERGENT NEAR THE KS/CO
BORDER...AND ALONG A SEPARATE CONFLUENCE LINE FARTHER E NEAR DDC
THAT DENOTES THE TRANSITION TO A COOLER/MOISTER ENVIRONMENT.  THE
00Z DDC SOUNDING REVEALED A RELATIVELY HIGH LFC HEIGHT AND
SUBSTANTIAL CONVECTIVE INHIBITION FOR 00Z...THUS NEW STORM
DEVELOPMENT IN THE SRN PART OF THE WATCH LOOKS QUESTIONABLE.

..THOMPSON/GUYER.. 05/25/2013

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

ATTN...WFO...GID...LBF...DDC...GLD...PUB...BOU...CYS...

LAT...LON   38880002 37750009 37320031 37070097 37040202 37590213
            38820208 39730244 40090340 40890365 41590330 41960259
            41930114 41700058 41400030 39980007 38880002