MESOSCALE PRECIPITATION DISCUSSION 0330
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
457 PM EDT TUE JUN 19 2018

AREAS AFFECTED...FAR SOUTH TEXAS

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

VALID 192056Z - 200200Z

SUMMARY...CELLS ENHANCING ON THE SOUTHEAST SIDE OF THE SOUTH TEXAS
MESO VORT.  SLOW MOVING CELLS WITH CONCENTRATED AREAS OF VERY
HEAVY RAINS WILL CONTINUE THROUGH THE LATE AFTERNOON INTO THIS
EVENING.

DISCUSSION...GOES-16 VISIBLE IMAGERY LATE THIS AFTERNOON CONTINUES
TO SHOW THUNDERSTORM ENHANCEMENT ACROSS FAR SOUTH TEXAS ON THE
SOUTHEAST SIDE OF THE SOUTH TEXAS MESO VORT.  MUCAPE VALUES ARE
THE GREATEST ACROSS FAR SOUTH TEXAS WITH VALUES 1500-2000+ J/KG AS
PER LATEST SPC MESOANALYSIS AND RAP32 MODEL FORECAST---WITH THESE
VALUES FORECAST TO PERSIST INTO THIS EVENING.  THE 1900 UTC HRRR
AND HRRR EXP SEEM TO HAVE THE BETTER HANDLE ON THE CURRENT
ACTIVITY AND SUGGEST CONTINUED HEAVY PRECIPITATION POTENTIAL
ACROSS SOUTH TEXAS AS MOIST SOUTH TO SOUTH SOUTHEAST LOW LEVEL
FLOW CONTINUES INTO THIS AREA. 

PRECIPITABLE WATER VALUES WILL REMAIN VERY ANOMALOUS---3+ STANDARD
DEVIATIONS ABOVE THE MEAN---2.25"+---HELPING TO MAINTAIN THE
HIGHLY EFFICIENT RAINFALL PROCESSES FOR ENHANCED RAINFALL RATES. 
RAINFALL RATES OF 2 TO 3 INCHES PER HOUR POSSIBLE INTO EARLY
EVENING IN REGIONS OF SLOWEST CELL MOTIONS.

ORAVEC

ATTN...WFO...BRO...

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

LAT...LON   27249762 27249759 27179747 27039712 26639677
            25999665 25439689 24839764 25109867 25669935
            26259933 26719896 26919857 26989841