MESOSCALE PRECIPITATION DISCUSSION 0361
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
959 AM EDT TUE JUN 26 2018

AREAS AFFECTED...SERN MO...SRN IL AND IN...KY

CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE

VALID 261358Z - 261900Z

SUMMARY...ATMOSPHERIC CONDITIONS APPEAR SUFFICIENT FOR MAINTENANCE
OF A CONVECTIVE COMPLEX MOVING EAST ACROSS THE OUTLINED AREA, WITH
SOME POTENTIAL FOR ADDITIONAL CELL DEVELOPMENT AHEAD OF THE
COMPLEX ALONG A SLOW-MOVING WARM FRONT. FLASH FLOODING IS POSSIBLE
THROUGH EARLY AFTERNOON.

DISCUSSION...A CONVECTIVE COMPLEX WAS ONGOING THIS MORNING FROM
SOUTHEASTERN MO INTO SOUTH CENTRAL IL, AND MOVING EASTWARD. HOURLY
RAINFALL RATES IN THE CONVECTION OF 1-1.5 IN/HR WERE ESTIMATED BY
RADAR. LATEST GOES-16 INFRARED IMAGERY INDICATE A SLIGHT WARMING
OF CLOUD TOPS, INDICATING PERHAPS MODEST WEAKENING OF THE
CONVECTIVE CORES. FARTHER EAST, SCATTERED CONVECTIVE CELLS WERE
PERSISTING IN THE VICINITY OF A SURFACE FRONT, WITH SOME CELL
REDEVELOPMENT/TRAINING OBSERVED, RESULTING IN HOURLY RAIN RATES
EXCEEDING 2 IN/HR FOR SOME AREAS. ATMOSPHERIC CONDITIONS APPEAR
FAVORABLE FOR CONTINUED MAINTENANCE OF THE COMPLEX, WITH
SUFFICIENT SHEAR (0-6 KM BULK SHEAR AROUND 30 KT) AND INSTABILITY
(MUCAPE OF 2000-3000 J/KG), AS WELL AS A MODEST DEGREE OF UPPER
DIFFLUENCE AHEAD OF AN UPPER LOW CROSSING THE MIDWEST.
ADDITIONALLY, THE 12Z RAOB FROM BNA ALONG WITH SPC MESOANALYSIS
SHOW AN AREA OF 700-500 HPA LAPSE RATES OF 7-7.5 DEG C/KM,
INDICATING THE PRESENCE OF AN ELEVATED NEAR-MIXED LAYER IN THE
WEAKLY CAPPED ENVIRONMENT SOUTH OF A STATIONARY SURFACE FRONT.

MOST HI-RES MODELS APPEAR TO HAVE A RELATIVELY POOR GRASP OF THE
SITUATION. THE EXPERIMENTAL HRRR SEEMS TO HAVE THE BEST HANDLE OF
THE ONGOING CONVECTION, AND SHOWS THE COMPLEX CONTINUING TO MOVE
EAST ACROSS THE OUTLINED AREA. ADDITIONALLY, LOCALIZED AREAS OF
TRAINING/REPEAT CELL DEVELOPMENT SHOULD CONTINUE IN THE VICINITY
OF THE SURFACE FRONT AHEAD OF THE COMPLEX. LOCALIZED AREAS OF 2-3
INCH RAINFALL AMOUNTS APPEAR POSSIBLE THROUGH 19Z. FLASH FLOOD
GUIDANCE VARIES ACROSS THE AREAS, BUT IN GENERAL, RAINFALL RATES
OF 1.5 IN/HR COULD POSE A PROBLEM FOR SOME AREAS GIVEN RECENT
LOCALLY HEAVY RAINS. THUS, FLASH FLOODING IS POSSIBLE THROUGH
EARLY AFTERNOON.

RYAN

ATTN...WFO...ILN...ILX...IND...JKL...LMK...OHX...PAH...

ATTN...RFC...LMRFC...NCRFC...OHRFC...

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            37568337 36958441 36698563 36698667 36648729
            36578841 36628959 36939003 37359000 37848959
            38438869 39078783