MESOSCALE PRECIPITATION DISCUSSION 0035
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1147 AM EDT FRI MAY 10 2013
 
AREAS AFFECTED...EXTREME SOUTHEAST TX...SOUTHWEST LA 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY 
 
VALID 101546Z - 101946Z
 
SUMMARY..FLASH FLOOD POTENTIAL IS EXPECTED TO INCREASE OVER THE
NEXT FEW HOURS AS AN APPROACHING CONVECTIVE COMPLEX MOVES OVER
SATURATED SOILS.

DISCUSSION...LATEST IR/VIS SATELLITE IMAGERY SHOWS A STRENGTHENING
MCS MOVING INTO EXTREME SOUTHEAST TX AND APPROACHING EXTREME
SOUTHWEST LA. PORTIONS OF THESE AREAS RECEIVED VERY HEAVY RAINFALL
AMOUNTS OVER THE LAST 12 HOURS FROM AN EARLIER MCS...AND THEREFORE
SOILS ARE NEARLY SATURATED. THIS LATEST MCS HAS A FAIRLY
WELL-DEFINED CONVECTIVE VORT WHICH IS SEEN HELPING TO ENHANCE THE
SOUTHERLY LOW LEVEL WARM/MOISTURE TRANSPORT INTO THE REGION. THIS
MOIST/UNSTABLE AIR IS SEEN OVERRUNNING AN OUTFLOW BOUNDARY THAT IS
SITUATED NEAR THE WESTERN GULF COAST AND HAD BEEN LAID DOWN FROM
THE EARLIER AFOREMENTIONED MCS. DYNAMICS ASSOCIATED WITH THE
CURRENT MCS AND INTERACTION WITH THE OUTFLOW BOUNDRY SHOULD FOSTER
AN AXIS OF VERY STRONG CONVECTION...THAT WILL HAVE POTENTIAL TO
TRAIN FOR THE NEXT SEVERAL HOURS INVOF THE UPPER TX COAST AND INTO
EXTREME SOUTHWEST LA. LATEST GOES-SOUNDER PWATS ARE ON THE ORDER
OF 1.7 TO 1.8 INCHES AND THIS WILL FOSTER RAINFALL RATES OF 2 TO 3
INCHES PER HOUR. GIVEN THIS AND POTENTIAL FOR TRAINING CONVECTION
...EXPECT AN ENHANCED THREAT FOR FLASH FLOODING.

ORRISON


ATTN...WFO...LCH...HGX...CRP...EWX...

LAT...LON   29639201 29569257 29669326 29489424 29029499 28689595
            28669635 28899673 29489666 30289543 30579370 30479275
            30139196 29639201 


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