MESOSCALE PRECIPITATION DISCUSSION 0583
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
757 AM EDT SAT AUG 20 2016
 
AREAS AFFECTED...NE TX...SE OK...SW AR 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY 
 
VALID 201156Z - 201656Z
 
SUMMARY...SYNOPTICALLY FORCED ASCENT WILL TAKE ADVANTAGE OF RICH
MOISTURE TO PRODUCE FAIRLY WIDESPREAD HEAVY RAIN THIS MORNING.
FLASH FLOODING IS LIKELY...ESPECIALLY IN NORTH TEXAS GIVEN THE
COMBINATION OF WET ANTECEDENT CONDITIONS AND PLACEMENT OF HEAVY
RAIN OVER THE DFW METROPLEX.

DISCUSSION...THERE WAS A GOOD DEAL OF MESOSCALE DETAIL TO BE
CONSIDERED IN THIS REGION GIVEN MULTIPLE OUTFLOWS FROM OVERNIGHT
CONVECTION. THE SYNOPTIC SITUATION...HOWEVER...APPEARS TO GIVE
SUFFICIENT INFORMATION TO MAKE A FORECAST OF CONTINUED CONVECTIVE
GROWTH AND SW-NE TRAINING OF HEAVY RAINFALL. A NORTHERN STREAM
TROUGH WAS AMPLIFYING...AND SIGNALS IN THE RAP AND GFS SUGGEST
INCREASED UPPER DIFLUENCE WASHING OVER THE DISCUSSION AREA AND
LASTING SEVERAL HOURS. WITH PLENTY OF UPSTREAM INSTABILITY IN THE
LOW LEVELS OVER TEXAS AND BROAD MOISTURE TRANSPORT WITHIN AN
AIRMASS CHARACTERIZED BY 2.0 TO 2.25 INCH PRECIPITABLE
WATER...RAINFALL SHOULD BECOME WIDESPREAD AND HEAVY TO LOCALLY
VERY HEAVY. WIND PROFILES FAVOR SW-NE TRAINING...WHICH MAY TURN
2.5 INCH PER HOUR RATES INTO 3 TO 5 INCH TOTALS PER THE HI-RES
GUIDANCE.

APPROACHING 12Z...ACTIVITY WAS MOST HEAVILY FOCUSED WITHIN A BAND
OVER NORTH TX WITHIN LOWER FFG AND APPROACHING THE METROPLEX.
FLASH FLOODING WOULD APPEAR TO BE LIKELY HERE. CONVECTION TOWARD
THE ARKLATEX AND CENTRAL AR MAY BECOME MORE FOCUSED AS SYNOPTIC
ASCENT INCREASES...AND DEVELOPMENT OF A SEPARATE...BROAD
LOW...OVER SOUTH TX...SETS UP A DEFORMATION ZONE THAT SHOULD ALLOW
FOR A WESTWARD EXTENSION OF SHALLOW...YET HEAVY AND SLOW MOVING
RAINFALL IN THE AREA SOUTH OF I-20 TOWARD BROWNWOOD TX.

BURKE

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

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

LAT...LON   35199350 34889157 33779202 32779457 31449879 
            31410068 32210016 32979843 34369579