MESOSCALE PRECIPITATION DISCUSSION 0339
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
518 PM EDT SUN JUN 12 2016
 
AREAS AFFECTED...NORTHERN TX 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 122115Z - 130030Z
 
SUMMARY...THUNDERSTORMS WITH VERY HEAVY RAINFALL MAY BECOME A BIT
MORE FOCUSED AND EXPANSIVE IN COVERAGE OVER THE NEXT FEW HOURS.
FLASH FLOODING IS GRADUALLY GOING TO BE A CONCERN TOWARD AND AFTER
00Z. 

DISUSSION...A VERY WELL-DEFINED MCV IS SEEN IN VIS IMAGERY MOVING
SLOWLY EAST ACROSS NORTH-CENTRAL TX TO THE SOUTHWEST OF THE
DALLAS/FORTH-WORTH METROPOLITAN AREA. MEANWHILE...AN OUTFLOW
BOUNDARY ASSOCIATED WITH THE INTENSE MORNING CONVECTION OVER
SOUTHERN OK HAS SHIFTED SOUTH ACROSS THE RED RIVER AND INTO NORTH
TEXAS. THERE IS ALREADY SOME INTERACTION OCCURRING BETWEEN THE MCV
AND THE OUTFLOW BOUNDARY GIVEN THE ERUPTION OF CONVECTION JUST
NORTHWEST OF THE DALLAS AREA. MLCAPE VALUES AROUND THE EASTERN
FLANK OF THE MCV ARE ON THE ORDER OF 2000 TO 3000 J/KG...WITH
PWATS OF CLOSE TO 2 INCHES. ADDITIONAL DIABATIC HEATING SHOULD
ENHANCE THE INSTABILITY A BIT FURTHER...AND THIS COUPLED WITH THE
MCV AND CLASHING MESOSCALE BOUNDARIES FROM EARLIER CONVECTION
SHOULD ALLOW FOR THE EXPANSION OF NEW CONVECTION THROUGH THE
LATE-AFTERNOON HOURS.

THE HIRES GUIDANCE INCLUDING THE HRRR/HRRRP AND 12Z NSSL-WRF TEND
TO HAVE THE BEST HANDLE ON THE CURRENT ACTIVITY OVERALL...BUT
THEIR FORECAST RAINFALL AMOUNTS THROUGH THE REMAINDER OF THE
AFTERNOON APPEAR TO BE A BIT UNDERDONE GIVEN SUCH A MOIST/UNSTABLE
AIRMASS AND THE EXPECTATION OF FAIRLY SLOW CELL MOTION. RAINFALL
RATES OF UP TO 2.5 INCHES/HR ARE LIKELY...AND THE THINKING RIGHT
NOW IS THAT AMOUNTS OF UP TO 4 TO 5 INCHES MAY BE POSSIBLE THROUGH
00Z FOR SOME AREAS AROUND THE NORTHERN AND EASTERN FLANKS OF THE
MCV. THIS SAME REGION WILL NEED TO BE MONITORED AFTER 00Z AS WELL
AS EVENTUALLY THE SAME MCV WILL BE INTERACTING WITH A GRADUALLY
INCREASING SOUTHERLY LOW LEVEL JET. WILL CONTINUE TO MONITOR.

ORRISON

ATTN...WFO...FWD...OUN...

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

LAT...LON   33949801 33839707 33249643 32599624 31919631 
            31439668 31119737 31059800 31339810 31729777 
            32029766 32359767 32599777 32869805 33039853 
            33569851