SPC MD 1365

MD 1365 CONCERNING SEVERE THUNDERSTORM WATCH 405… FOR PORTIONS KS…SRN NEB…WRN/NRN MO.


MESOSCALE DISCUSSION 1365
NWS STORM PREDICTION CENTER NORMAN OK
1026 PM CDT TUE JUL 09 2013

AREAS AFFECTED...PORTIONS KS...SRN NEB...WRN/NRN MO.

CONCERNING...SEVERE THUNDERSTORM WATCH 405...

VALID 100326Z - 100530Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 405
CONTINUES.

SUMMARY...PRIMARY AREA OF STG-SVR TSTMS OVER CENTRAL/E-CENTRAL KS
MAY CONTINUE TO POSE RISK OF SVR WIND/HAIL AS IT MOVES ACROSS ERN KS
AND PERHAPS INTO PORTIONS NRN MO...WHICH MAY REQUIRE WW.  CONVECTION
HAS DIMINISHED CONSIDERABLY OVER NEB AND NWRN KS...WITH BOUNDARY
LAYER STABILIZED BY COMBINATION OF OUTFLOW AND DIABATIC COOLING.  AS
SUCH...SOME OF THESE AREAS MAY BE CLEARED FROM WW IF NO OTHER
SUBSTANTIAL CONVECTION DEVELOPS.

DISCUSSION...SFC COLD FRONT WAS DRAWN FROM SWRN WI SWWD ACROSS SWRN
IA TO KS/NEB BORDER BETWEEN MCK-HLC.  FRONT HAS BECOME DIFFUSED
SOMEWHAT BY OUTFLOW FROM EARLIER CONVECTION OVER S-CENTRAL NEB AND
N-CENTRAL KS.  WEAK/PREFRONTAL BOUNDARY IS EVIDENT IN SFC DATA AND
REFLECTIVITY ANIMATIONS FROM CNK AREA ESEWD ACROSS NRN PORTIONS MKC
METRO...WHERE IT HAS BEEN SUBTLY REINFORCED BY OUTFLOW FROM
EARLIER/TRANSIENT TSTM THAT DEVELOPED THEREON.  THIS BOUNDARY IS
MOVING SWD ABOUT 10 KT IN PRECONVECTIVE AIR MASS...AND APPEARS TO BE
FOCUSING ADDITIONAL DEVELOPMENT NEAR MHK AND BETWEEN MHK-TOP.

MODIFIED TOP RAOB AND MODEL SOUNDINGS SUGGEST I-70 CORRIDOR LIES
ALONG SRN RIM OF MOST FAVORABLE DEEP SHEAR AND BUOYANCY...WITH
EFFECTIVE SHEAR MAGNITUDES 40-50 KT N OF ABOUT A CNK-STJ-UIN LINE.
THAT AREA SWD TO I-70 ALSO IS IN SRN GRADIENT OF ENHANCED BUOYANCY
LOCATED OVER NERN KS AND NRN MO...WITH MLCAPE 2500-3000 J/KG FOR
TSTMS THAT CAN ACCESS SFC-BASED EFFECTIVE INFLOW PARCELS.
HOWEVER...CINH WILL INCREASING ACROSS THIS AREA GRADUALLY...GIVEN
RICH LOW-LEVEL MOISTURE WITH SFC DEW POINTS COMMONLY 70S F.
INCREASING/SWLY/30-35 KT LLJ WILL BE MAINTAINED OVER ERN KS AND
CENTRAL/NRN MO FOR SEVERAL MORE HOURS...HELPING TO MAINTAIN HIGH
THETAE ABOVE SFC.  SVR POTENTIAL DOWNSHEAR WILL BE DEPENDENT ON
BETTER-ORGANIZED COLD POOL THAN IS EVIDENT AT PRESENT...TO MAXIMIZE
FORCED ASCENT AND SUSTAINABLE FORWARD PROPAGATION.  AS
SUCH...CONVECTIVE TRENDS WILL BE MONITORED FOR POSSIBILITY OF WW
FARTHER E OVER MO.

..EDWARDS.. 07/10/2013

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

ATTN...WFO...LSX...SGF...EAX...OAX...TOP...ICT...GID...DDC...
GLD...

LAT...LON   39510006 40359993 40989852 40569598 40379346 39789226
            39299222 38539270 38089355 37909457 37919622 37999780
            38569916 38859954 39510006

via SPC Forecast Products http://www.spc.noaa.gov/products/md/md1365.html