MESOSCALE PRECIPITATION DISCUSSION 0215
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
538 AM EDT MON JUN 15 2015
 
AREAS AFFECTED...PORTIONS OF CNTRL/S-CNTRL TEXAS TO THE GULF COAST 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 150935Z - 151500Z
 
SUMMARY...THE COVERAGE OF SCATTERED SHOWERS MOVING INLAND FROM THE
CNTRL TEXAS COAST IS EXPECTED TO INCREASE THROUGH EARLY
MORNING...CONTAINING RAINFALL RATES UP TO 2 IN/HR. THE CONCERN FOR
FLASH FLOODING IS ACROSS LOCATIONS THAT RECEIVED HEAVY RAINFALL
SUNDAY...LOWERING FLASH FLOOD GUIDANCE TO 1-2 IN/HR. 

DISCUSSION...REGIONAL RADAR IMAGERY AS OF 09Z SHOWED WIDELY
SCATTERED SHOWERS STREAMING IN FROM THE CNTRL TEXAS COAST INTO
PORTIONS OF S-CNTRL TEXAS. ANOMALOUS MOISTURE IS ADVECTING INLAND
IN ASSOCIATION WITH A DISORGANIZED AREA OF LOW PRESSURE LOCATED IN
THE W-CNTRL GULF OF MEXICO...BEING TRACKED BY THE NATIONAL
HURRICANE CENTER. GPS PW VALUES ACROSS THE REGION WERE BETWEEN 1.8
AND 2.0 INCHES...INDICATIVE OF A VERY MOIST AIRMASS WITH
TROPICAL-LIKE CHARACTERISTICS. 

PORTIONS OF THE SAN ANTONIO METRO AREA DOWN TOWARD MATAGORDA BAY
RECEIVED 3-6 INCHES OF RAIN YESTERDAY...LOCALLY...WHICH HAS
SIGNIFICANTLY LOWERED FLASH FLOOD GUIDANCE COMPARED TO SURROUNDING
LOCATIONS. AREA VAD WIND PROFILE PLOTS OF 850 MB WINDS SHOWED 10
TO 20 KTS OF SELY FLOW FROM THE CNTRL TEXAS COAST INTO THE TEXAS
HILL COUNTRY WITH WEAK LOW LEVEL CONFLUENCE NOTED IN THE VICINITY
OF THE HILL COUNTRY. WHILE RECENT RUNS OF THE RAP SUPPORT THESE
WINDS WEAKENING WHILE SLOWLY BACKING TOWARD THE EAST BY 15Z...DEEP
TROPOSPHERIC FLOW IS FORECAST TO BE 20 KTS OR LESS WHICH WILL
SUPPORT SLOW MOVEMENT OF STORMS. WHILE ORGANIZATION OF CONVECTION
IS EXPECTED TO BE LACKING...SUNRISE MAY CONTINUE TO BRING ABOUT
ADDITIONAL STORMS AS NOTED IN THE 00Z SPC WRF SIMULATED
REFLECTIVITY. GRANTED MODEL SUPPORT IS NOT GREAT FOR FLASH
FLOODING...BUT IT WAS ALSO LACKING ON SUNDAY...AND TRENDS SEEM TO
BE GOING AGAINST THE MODEL MAJORITY AT THE MOMENT.

OTTO

ATTN...WFO...CRP...EWX...FWD...HGX...SJT...

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

LAT...LON   30829744 30539641 29909559 29379502 28929494 
            28449574 28009664 27689706 27619761 28279895 
            29029973 29509987 30229951 30809847