MESOSCALE PRECIPITATION DISCUSSION 0341
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
342 AM EDT MON JUN 19 2017

AREAS AFFECTED...NRN TEXAS INTO FAR SERN OK/SWRN AR

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

VALID 190741Z - 191315Z

SUMMARY...SLOW MOVING THUNDERSTORMS WITH BRIEF TRAINING CONTAINING
RAINFALL RATES OF 1-2 IN/HR ARE EXPECTED TO DEVELOP INTO NRN/NERN
TX AND FAR SERN OK/SWRN AR. THESE STORMS MAY CAUSE 3-5 INCH TOTALS
AND LOCALIZED FLASH FLOODING THROUGH 13Z.

DISCUSSION...OVER THE PAST HOUR...EXPERIMENTAL GOES 16 10.3 MICRON
IMAGERY HAS SHOWN A RAPID EXTENSION AND EXPANSION OF COLDER CLOUD
TOPS TO THE WSW OF ONGOING SHOWERS AND THUNDERSTORMS LOCATED IN
SERN OK. BRIEF TRAINING OF SMALL RAINFALL CORES HAS ALREADY BEEN
OBSERVED OVER PORTIONS OF SRN OK. THESE STORMS ARE ELEVATED IN
NATURE AND APPEAR TO BE LOCATED ALONG THE 850 MB REFLECTION OF A
FRONTAL BOUNDARY DRAPED SWWD FROM SRN AR INTO NERN AND CNTRL TX.
THE BOUNDARY HAS BEEN SLOWLY SINKING SOUTH OVER THE PAST FEW HOURS
AND HAS MET WITH AN ENVIRONMENT CHARACTERIZED BY HIGHER CAPE
VALUES THAN WHAT HAS BEEN OBSERVED IN CNTRL OK. THE LATEST SPC
MESOANALYSIS PLACES 1500-3000 J/KG MUCAPE ALONG THE RED RIVER
VERSUS 500-1000 FARTHER NORTH.

INDIVIDUAL CELLS OVER S-CNTRL OK HAVE BEEN AVERAGING 10-15 KT
TOWARD THE SOUTHEAST. RAP ANALYSES AND AREA VAD WIND PLOTS SHOWED
A CORRIDOR OF STRONGER 700 MB FLOW...25-30 KT...LOCATED BETWEEN
FDR/DYS AND EXTENDING EAST TO I-35 IN NORTH TX. THE ONGOING AREA
OF CONVECTION IN S-CNTRL AND SERN OK IS EXPECTED TO CONTINUE
MOVING SOUTH THROUGH 13Z OR 14Z AND FOR STORMS ROOTED CLOSER TO
700 MB...BRIEF TRAINING OF CELLS IS EXPECTED TO BECOME MORE
WIDESPREAD. GIVEN RAINFALL RATES OF 1-2 IN/HR AND THE SLOW
MOVEMENT EXPECTED...3-5 INCHES IN A 2 OR 3 HOUR PERIOD SEEMS
LIKELY WHICH WOULD CAUSE LOCALIZED FLASH FLOODING. THE COVERAGE OF
3-5 INCH RAINFALL SHOULD NOT BE WIDESPREAD WITHIN THE MPD THREAT
AREA AND HIGHER FLASH FLOOD GUIDANCE VALUES OF 3-5 INCHES IN 3
HOURS SHOULD KEEP FLASH FLOODING LIMITED TO JUST A FEW LOCATIONS.

OTTO

ATTN...WFO...FWD...LZK...OUN...SHV...TSA...

ATTN...RFC...ABRFC...LMRFC...WGRFC...

LAT...LON   34559440 34299365 33849359 33249400 32779564
            32739726 33179822 33589856 34089790 34469611