MESOSCALE PRECIPITATION DISCUSSION 0186
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
930 PM EDT MON JUL 29 2013
 
AREAS AFFECTED...SOUTHERN AND EASTERN KS...NORTHERN
OK...SOUTHWESTERN MO...NORTHWESTERN AR 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY 
 
VALID 300130Z - 300700Z
 
SUMMARY...SIGNIFICANT FLASH FLOODING IS EXPECTED OVERNIGHT AS
NUMEROUS ORGANIZING CONVECTIVE CLUSTERS MERGE INTO A SLOW-MOVING
MESOSCALE CONVECTIVE SYSTEM (MCS).

DISCUSSION...LATEST IR SAT IMAGERY SHOWS VERY COLD-TOPPED
CONVECTIVE CLUSTERS WITH A NUMBER OF OVERSHOOTING TOPS IMPACTING
MUCH OF FAR NORTHERN OK AND ADJACENT AREAS OF E CNTRL AND SERN KS.
CLOUD TOPS HAVE COOLED TO -75 TO -80C  INDICATIVE OF POWERFUL
UPDRAFTS AND SUPPORTIVE OF VERY INTENSE RAINFALL RATES. THE LATEST
RAP ANALYSIS SHOWS A POOL OF 2.1 TO 2.3 INCH PWATS FROM THE RED
RIVER VALLEY NORTHWARD INTO SERN KS...AND COINCIDING WITH SBCAPE
VALUES OF 3000 TO 3500 J/KG. ALL THE WHILE...THERE IS A
WELL-DEFINED SHORTWAVE TROUGH MOVING STEADILY EASTWARD ACROSS
WRN/CNTRL KS ATTM WITH A SWWD ORIENTED TAIL OF VORTICITY EXTENDING
DOWN INTO WRN OK/NRN TX. SFC ANALYSIS CONTINUES TO SHOW A
STATIONARY FRONT IN A WAVY FASHION ORIENTED FROM SWRN MO WEST BACK
INTO S CNTRL KS TO AN AREA OF LOW PRESSURE...WITH A TAILING COLD
FRONT INTO THE OK/TX PANHANDLES.

OVER THE NEXT SEVERAL HOURS...THE ONGOING FLASH FLOOD THREAT WILL
EVOLVE ESEWD THROUGH SERN KS...NRN/NERN OK...AND INTO SWRN MO...AS
ORGANIZING CONVECTIVE CLUSTERS MERGE AND EVOLVE INTO A LARGER
SCALE MCS. THE LATEST MODEL GUIDANCE SUPPORTS AN INCREASING S/SWLY
LOW LEVEL JET OVERNIGHT...INCREASING TO 40 TO 50 KTS...WHICH WILL
SUSTAIN A VERY MOIST/UNSTABLE AIR TRANSPORT REGIME INTO THE MCS.
SUSTAINABLE STRONG CONVECTIVE CORES WITH RAINFALL RATES UPWARDS OF
3 INCHES/HR CAN BE EXPECTED.

LATEST RAP ANALYSIS CONTINUES TO SHOW NEARLY PARALLEL MEAN LYR
FLOW INVOF THE AFOREMENTIONED W/E ORIENTED FRONT AND ONGOING
CONVECTIVE MASS. THIS COUPLED THE LOW LVL JET BEING NEARLY
PERPENDICULAR TO THE BOUNDARY SUGGESTS A HIGH THREAT OF
BACK-BUILDING AND TRAINING CONVECTION. GIVEN THE EXPECTED RAINFALL
RATES...EXTREMELY HVY RAINFALL AMTS WILL BE POSSIBLE.

CONSEQUENTLY...THE POTENTIAL CONTINUES FOR A HIGH-IMPACT FLASH
FLOOD EVENT INTO THE OVERNIGHT HOURS...AND ESPECIALLY WITH LOCALLY
SATURATED SOIL CONDITIONS.

ORRISON

ATTN...WFO...LZK...SGF...EAX...TSA...TOP...ICT...OUN...DDC...
AMA...

ATTN...RFC...ABRFC...LMRFC...MBRFC...

LAT...LON   36959976 37619822 39089613 39199462 38679350 37969270
            37199237 36339248 35709327 35309431 35229596 35559808
            35920009 36510049 36959976