MESOSCALE PRECIPITATION DISCUSSION 0303...CORRECTED
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
336 PM EDT FRI JUN 03 2016
 
CORRECTED FOR GRAPHIC

AREAS AFFECTED...SOUTHERN TX 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 031931Z - 040131Z
 
SUMMARY...THUNDERSTORMS ARE INCREASING IN COVERAGE AND INTENSITY
WITHIN AN UNSTABLE ENVIRONMENT.  HOURLY RAIN RATES UP TO 2" COULD
LEAD TO FLASH FLOODING.

DISCUSSION...THUNDERSTORMS WITH COOLING CLOUD TOPS HAVE BEEN
DEVELOPING IN SOUTHERN TX DURING THE PAST HOUR NEAR A MESOSCALE
WAVE ALONG A THERMAL GRADIENT ACROSS SOUTH-CENTRAL TX AND ALONG A
DEW POINT GRADIENT TO ITS SOUTH IN DEEP SOUTH TX.  PRECIPITABLE
WATER VALUES OF 1.5-1.9" EXIST ACROSS THE REGION PER GPS VALUES. 
MLCAPES ARE UP TO 2500-3000 J/KG PER SPC MESOANALYSES.  LOW-LEVEL
INFLOW IS CONVERGENT OUT OF THE SOUTHWEST AT 15 KTS WHILE 0-6 KM
BULK SHEAR VALUES ARE SUFFICIENT TO ORGANIZE CONVECTION.

THE CAM/MESOSCALE GUIDANCE SHOWS LOCAL AMOUNTS OF 2-4" IN THIS
AREA, WHICH COULD FALL QUICKLY.  THE AVAILABLE MOISTURE AND
INSTABILITY IMPLY RAIN RATES WHICH COULD PEAK NEAR 2".  THESE RAIN
AMOUNTS SHOULD CHALLENGE THE THREE HOURLY FLASH FLOOD GUIDANCE
VALUES, AND COULD CAUSE ISSUES IN URBAN AREAS.  THE 12Z SSEO
NEIGHBORHOOD PROBABILITIES OF EXCEEDING THE THREE HOUR FLASH FLOOD
GUIDANCE IMPLY THE HEAVY RAINFALL WOULD PEAK IN THE 22-01Z TIME
FRAME.

ROTH

ATTN...WFO...BRO...CRP...EWX...HGX...

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

LAT...LON   29369836 29199641 28839571 27949677 27209727 
            25909707 25759748 25949827 26309868 27969844 
            28809892