MESOSCALE PRECIPITATION DISCUSSION 0239
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
907 PM EDT WED JUN 17 2015
 
AREAS AFFECTED...SRN OK...CENTRAL OK...ERN OK...NRN TX...WRN AR 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY 
 
VALID 180107Z - 180707Z
 
SUMMARY...A DANGEROUS FLASH FLOOD EVENT WAS UNFOLDING IN THE
ARBUCKLE MOUNTAINS OF SOUTHERN OK. EXCESSIVE RAINFALL WILL ALSO
FALL ON A BROAD PART OF OKLAHOMA AND ADJACENT NORTH TX AND WESTERN
AR TONIGHT.

DISCUSSION...OKLAHOMA MESONET OBSERVATIONS REVEALED INTENSE RAIN
RATES NEAR ARDMORE OK...AS EASTERLY FLOW AROUND THE CENTER OF T.D.
BILL WAS PRODUCING UPSLOPE FORCING INTO THE ARBUCKLE MOUNTAINS. AS
OF 0045Z RATES OF 5 INCHES IN 2 HOURS HAD BEEN MEASURED. TEH
CENTER OF BILL WAS LOCATED ABOUT 40 MILES SOUTH OF THIS AREA...AND
THE RAP MAINTAINS STOUT EASTERLY LOW LEVEL FLOW THROUGH AT LEAST
03Z. THE MESONET STATION AT NEWPORT HAD TOPPED 8 INCHES AND MAY
EXCEED 12 INCHES BEFORE THE EVENT THERE EASES.

A MORE GENERAL RAINFALL OF AT LEAST 4 TO 6 INCHES IS LIKELY...AND
APPEARS IN ALL THE MODEL SOLUTIONS FOR TONIGHT IN PARTS OF
SOUTHERN...CENTRAL...AND EASTERN OK. THE WPC QPF WAS INCREASED AND
REPOSITIONED SLIGHTLY NORTHWEST...PLACING MORE OF THE SOUTHERN AND
EASTERN SIDES OF THE OKLAHOMA CITY METRO AT A HIGH RISK OF
EXCESSIVE RAINFALL. PARTS OF EASTERN OK INCLUDING TULSA WERE ALSO
RECEIVING HEAVY RAIN...WHICH WILL ONLY INTENSIFY AS BILL
APPROACHES. GIVEN THE SIZE OF THE CYCLONE...FEEDER BANDS OVER
WESTERN ARKANSAS MAY CONTINUE THROUGH FORCING DESPITE LOSS OF
HEATING...AND WHILE MOVING MORE QUICKLY...THEY WILL DUMP HEAVY
RAIN LOCALLY IN A SHORT TIME WITHIN HILLY TERRAIN. 

THE ONLY SILVER LINING SEEMS TO BE THE LACK OF INSTABILITY GIVEN
EXTENSIVE CONVECTION IN THE INFLOW REGION OVER TEXAS. STILL...THE
OUTLINED REGION SHOULD BE EXTREMELY SUSCEPTIBLE TO FLASH FLOODING.
OK MESONET DATA INDICATES THE BRIEF DRYING OF SOILS IN EARLY JUNE
HAD ALREADY BEEN REVERSED BY RECENT RAINY DAYS...WITH MOST SITES
MEASURING FRACTIONAL SOIL MOISTURE NEAR 100 PERCENT FOR ALL DEPTHS.

BURKE

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

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

LAT...LON   36629575 36489456 36159342 35529296 34959303 
            34619356 34769400 34609458 33569529 33169602 
            33039687 33229785 34389842 35519766 36319653