MESOSCALE PRECIPITATION DISCUSSION 0666
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
400 AM EDT FRI AUG 11 2017

AREAS AFFECTED...CENTRAL/EASTERN OK

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

VALID 110755Z - 111200Z

SUMMARY...A STRONG MCS MOVING ACROSS CENTRAL OK AT THIS TIME WILL
CONTINUE TO ADVANCE EAST-SOUTHEAST OVER THE NEXT COUPLE OF HOURS.
SOME ADDITIONAL HEAVY RAINFALL IS EXPECTED...WITH A GRADUAL
WEAKENING TREND TOWARD AND AFTER DAWN.

DISCUSSION...AN IMPRESSIVELY COLD-TOPPED MCS IS SEEN MOVING ACROSS
CENTRAL OK CURRENTLY...BRINGING RAINFALL AMOUNTS UP TO OVER 2
INCHES/HR LOCALLY. SOME OF THE HEAVIEST RAINS CURRENTLY ARE OVER
NORTHERN OK AND CURRENTLY APPROACHING THE PONCA CITY AREA.

A CONSENSUS OF THE HIRES GUIDANCE SUPPORTS THE MCS MAINTAINING
ITSELF FOR A COUPLE MORE HOURS AND THEN GRADUALLY WEAKENING AS IT
BEGINS TO OUTRUN THE MOST FAVORABLE SOUTHWEST LOW LEVEL JET ENERGY
LIFTING UP ACROSS THE SOUTHERN PLAINS. THE DOWNSTREAM ENVIRONMENT
OVER EASTERN OK REMAINS FAIRLY UNSTABLE...BUT THERE IS A GROWING
AMOUNT OF LOW LEVEL CIN WHICH WILL EVENTUALLY HELP TO FACILITATE A
WEAKENING TREND TO THE CONVECTION TOWARD DAWN.

NEVERTHELESS...THERE WILL LIKELY BE POCKETS OF 2 TO 4 INCHES
WITHIN JUST A COUPLE OF HOURS IN ASSOCIATION WITH THE MCS AS IT
CONTINUES TO ADVANCE EAST. GIVEN THE INTENSE SHORT-TERM RAIN
RATES...SOME FLASH FLOODING WILL BE POSSIBLE. ALSO...THE RADAR
IMAGERY IS SHOWING SOME ELEVATED CONVECTION REDEVELOPING OVER
PARTS OF THE TX PANHANDLE WHICH IS ADVANCING EAST-SOUTHEAST AND
MAY TRAIN OVER SOME OF THE SAME AREAS IN SOUTHWEST OK THAT HAVE
ALREADY SEEN HEAVY RAIN WITH THE INITIAL MCS ARRIVAL. AN
ADDITIONAL 1 TO 3 INCHES OF RAIN WITH THIS ACTIVITY CANNOT BE
RULED OUT...WHICH MAY ENCOURAGE ADDITIONAL RUNOFF PROBLEMS.

ORRISON

ATTN...WFO...AMA...ICT...OUN...TSA...

ATTN...RFC...ABRFC...

LAT...LON   37079630 36999562 36749484 36119456 35289465
            34469517 34049615 34109770 34319923 34659992
            35060011 35410000 35709952 35779872 36039839
            36369859 36619881 36899868 37059757