MESOSCALE PRECIPITATION DISCUSSION 0633
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
836 PM EDT SAT AUG 05 2017
AREAS AFFECTED...SOUTHERN/EASTERN KS...NORTHERN
OK...WESTERN/SOUTHERN MO
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY
VALID 060030Z - 060630Z
SUMMARY...MULTIPLE BANDS/CLUSTERS OF SHOWERS AND THUNDERSTORMS
WITH HEAVY RAINFALL ARE EXPECTED INTO THE OVERNIGHT HOURS. FLASH
FLOODING IS LIKELY AND COULD BE LOCALLY SIGNIFICANT GIVEN THE WET
ANTECEDENT CONDITIONS.
DISCUSSION...RADAR IMAGERY CONTINUES TO SHOW A BAND OF ELEVATED
CONVECTION FROM NEAR THE KANSAS CITY METROPOLITAN AREA SOUTHEAST
DOWN ACROSS MUCH OF CENTRAL MO AT THIS TIME. THE ACTIVITY
CONTINUES TO BE FACILITATED BY THE PRESENCE OF A MODERATELY STRONG
SOUTHWEST LOW LEVEL JET WHICH IS TRANSPORTING PLENTY OF
MOIST/UNSTABLE AIR OVER TOP A SURFACE COLD POOL GENERATED FROM
EARLY DAY CONVECTION. THE RESULTING WARM ADVECTION/ISENTROPIC LIFT
REGIME COUPLED WITH SOME RIGHT-ENTRANCE REGION UPPER JET SUPPORT
HAS BEEN FACILITATING REPEATING CELLS OVER THE SAME AREA AND THIS
IS CONTINUING TO MOISTEN AND SATURATE THE SOIL CONDITIONS.
MEANWHILE...LATE-DAY NON-OPERATIONAL GOES-16 IR/VIS IMAGERY SHOWS
PLENTY OF HEAVY SHOWER AND THUNDERSTORM ACTIVITY ERUPTING OVER
SOUTHERN KS AND ADJACENT AREAS OF FAR NORTHERN OK. THIS IS
OCCURRING WITHIN A NOTABLY MOIST AND UNSTABLE WARM-SECTOR AIRMASS
CHARACTERIZED BY 1.6 TO 1.8 INCH PWATS AND UPWARDS OF 2000 J/KG OF
MLCAPE WHICH IS ALSO BUMPING UP AGAINST AND NOW OVERRUNNING A
WELL-DEFINED OUTFLOW BOUNDARY WHICH DELINEATES THE LEADING EDGE OF
THE AFOREMENTIONED COLD POOL OVER SOUTH-CENTRAL AND SOUTHEAST KS.
THE CONVECTIVE THREAT IS EXPECTED TO INCREASE MARKEDLY OVERNIGHT
ACROSS AREAS OF NORTHEAST KS DOWN INTO CENTRAL MO...INCLUDING THE
KANSAS CITY METROPOLITAN AREA. A SEPARATE AREA OF CONCERN WILL
ALSO EXIST ACROSS PARTS OF SOUTHEAST KS WHERE ALREADY UPWARDS OF 6
INCHES OF RAIN HAS FALLEN SINCE EARLY THIS MORNING.
THE ENHANCED CONVECTIVE THREAT WILL BE FACILITATED BY FURTHER
STRENGTHENING OF THE SOUTHWEST LOW LEVEL JET ASSOCIATED WITH AN
APPROACHING SHORTWAVE TROUGH AND ASSOCIATED AREA OF SURFACE LOW
PRESSURE. THE LOW LEVEL JET IS FORECAST TO INCREASE TO 40 TO 50
KTS TOWARD 06Z...AND THIS WILL DRIVE STRONGER MOISTURE/INSTABILITY
TRANSPORT IN AN ELEVATED FASHION OVER THE AFOREMENTIONED COLD POOL
AND WITH INTERACTION INVOLVING THE 925/850 MB WARM FRONT FOCUSED
FROM NORTHEAST KS DOWN ACROSS CENTRAL MO.
THE AFOREMENTIONED OUTFLOW BOUNDARY SHOULD TEND TO RETREAT
NORTHEASTWARD WITH TIME...BUT VERY HEAVY RAINS WILL BE FOCUSING
ALONG AND NORTH OF THIS BOUNDARY OVER PARTS OF SOUTHERN/SOUTHEAST
KS AND POSSIBLY NORTHERN OK. MEANWHILE...FARTHER NORTH THE
ELEVATED WARM FRONT WILL TEND TO BE A SEPARATE FOCUS WHERE THE LOW
LEVEL JET INTERACTING WITH THIS BOUNDARY COUPLED WITH SOME
STRENGTHENING OF RIGHT-ENTRANCE REGION JET DYNAMICS WILL ALLOW FOR
A FOCUSED AXIS OF STRONG AND POSSIBLY TRAINING THUNDERSTORMS WITH
VERY HEAVY RAINFALL RATES.
AS SUGGESTED BY THE LATEST HRRR GUIDANCE...EXPECT RAINFALL RATES
OF AS MUCH AS 2.5 INCHES/HR...AND ADDITIONAL RAINFALL TOTALS OF 3
TO 6+ INCHES FROM NORTHEAST KS TO CENTRAL MO THROUGH 06Z.
MEANWHILE...EXPECT SIMILAR AMOUNTS TO BE POSSIBLE OVER PARTS OF
SOUTHERN/SOUTHEAST KS AND FAR NORTHERN OK. FLASH FLOODING IS
LIKELY...AND SOME OF IT COULD BE SIGNIFICANT GIVEN EARLIER
RAINFALL AND POTENTIALLY ENHANCED URBANIZED RUNOFF CONCERNS.
ORRISON
ATTN...WFO...DDC...EAX...ICT...LSX...OUN...PAH...SGF...TOP...
TSA...
ATTN...RFC...ABRFC...LMRFC...MBRFC...NCRFC...
LAT...LON 39829477 39549329 39149225 38669148 38109082
37309046 36909057 36729104 36919207 37049356
36929455 36479573 36029697 35849815 35839938
36019982 36279988 36879938 37759852 38199793
38649756 39129728 39569671 39789597
Last Updated: 836 PM EDT SAT AUG 05 2017