SPC MD 1561

MD 1561 CONCERNING SEVERE POTENTIAL…WATCH POSSIBLE FOR PORTIONS OF SWRN/S-CNTRL MO…EXTREME SERN KS…FAR NRN AR…FAR NERN OK


MESOSCALE DISCUSSION 1561
NWS STORM PREDICTION CENTER NORMAN OK
0603 PM CDT MON JUL 29 2013

AREAS AFFECTED...PORTIONS OF SWRN/S-CNTRL MO...EXTREME SERN KS...FAR
NRN AR...FAR NERN OK

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 292303Z - 300130Z

PROBABILITY OF WATCH ISSUANCE...40 PERCENT

SUMMARY...THE AREA IS BEING MONITORED FOR AN INCREASING POTENTIAL
FOR SVR STORMS THROUGH THIS EVENING. THE ISSUANCE OF A WW TO THE E
OF ONGOING SVR TSTM WATCH 450 IS POSSIBLE.

DISCUSSION...DEEP FORCING FOR ASCENT WILL GRADUALLY RAMP UP DURING
THE NEXT SEVERAL HOURS...LEADING TO AN INCREASE IN THE POTENTIAL FOR
INTENSE CONVECTION THROUGH THE EVENING. WATER VAPOR DATA INDICATE
THE EXIT REGION OF A MID-LEVEL SPEED MAX APPROACHING THE AREA. IN
ASSOCIATION WITH THIS FEATURE...INCREASING WARM ADVECTION HAS
ALREADY BEEN MANIFESTED BY AN UPTICK IN REFLECTIVITY RETURNS OVER
PARTS OF SWRN MO...AND ADDITIONAL CONVECTION MAY DEVELOP IN THIS
AREA DURING THE NEXT FEW HOURS. AT THE SAME TIME...CLUSTERS OF
INTENSE CONVECTION OVER SRN KS WILL HAVE A TENDENCY TO FORWARD
PROPAGATE TOWARD THE MO OZARKS DURING THE EVENING/OVERNIGHT
HOURS...AS A LLJ STRENGTHENS TO 30-40 KT WITH ITS TERMINUS OVERLYING
THE AREA. WHILE MID-LEVEL LAPSE RATES ARE NOT PARTICULARLY
STEEP...RICH BOUNDARY-LAYER MOISTURE WILL YIELD AT LEAST MODERATE
INSTABILITY NEAR AND S OF A FRONT THAT ARCS FROM SWRN MO INTO
N-CNTRL/NERN AR. THE INCREASING MERIDIONAL FLOW COMPONENT IN THE LOW
LEVELS WILL SERVE IN THE NWD-MOTION OF THIS BOUNDARY AS A WARM
FRONT. THIS COULD ACT TO SUPPORT BOUNDARY-LAYER DESTABILIZATION
FARTHER N IN MO DURING THE EVENING.

DEEP SHEAR WILL BE SUFFICIENT FOR ORGANIZED CONVECTIVE
CLUSTERS...POTENTIALLY WITH DMGG WINDS AND SVR HAIL...AND SOME
TORNADO POTENTIAL MAY EXIST WITH BACKED SFC FLOW NEAR AND JUST N OF
THE FRONT. THERE IS UNCERTAINTY REGARDING THE MAINTENANCE OF SVR
POTENTIAL AS NOCTURNAL COOLING OCCURS THIS EVENING...THOUGH TRENDS
WILL BE MONITORED FOR THE POSSIBLE ISSUANCE OF A WW.

..COHEN/CORFIDI.. 07/29/2013

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

ATTN...WFO...LZK...SGF...EAX...TSA...

LAT...LON   36379398 36669496 37929496 38439361 38129242 37389199
            36519254 36379398

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