MESOSCALE PRECIPITATION DISCUSSION 0619
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
410 AM EDT FRI OCT 30 2015
 
AREAS AFFECTED...PORTIONS OF CNTRL TEXAS 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 300809Z - 301400Z
 
SUMMARY...THE BEGINNING OF AN ANTICIPATED HEAVY RAIN EVENT APPEARS
TO BE UNDERWAY WITH POSSIBLE FLASH FLOODING DEVELOPING BY 12Z
ACROSS PORTIONS OF CNTRL TEXAS. RAINFALL RATES OF 2-3 INCHES IN 3
HOURS ARE EXPECTED.

DISCUSSION...RAPID LOW LEVEL MOISTURE RETURN HAS BEEN OBSERVED
OVER SRN AND S-CNTRL TEXAS OVER THE PAST 6-12 HOURS WITH
APPROXIMATELY 0.50 INCH RISES IN PRECIPITABLE WATER SEEN AT
SEVERAL SITES ACROSS SRN AND S-CNTRL TEXAS. SELY NEAR-SURFACE FLOW
AND SLY FLOW AT 850 MB OF 30-40 KTS...AS SEEN ON VAD WIND
PLOTS...IS HELPING TO DEEPEN LOW LEVEL MOISTURE PROFILES ACROSS
THE REGION ALLOWING WEAK INSTABILITY...LESS THAN 1000 J/KG...TO
DEVELOP NWD TOWARD BETWEEN I-10 AND I-20...JUST WEST OF I-35. 

DEEP SLY TO SWLY FLOW IS IN PLACE ACROSS TEXAS AHEAD OF A
DEEPENING/ROBUST UPPER TROUGH OVER THE SOUTHWEST. GIVEN THESE WIND
PROFILES...REGIONAL RADAR SHOWED SW-NE TRAINING RAINFALL ACROSS
SHACKELFORD AND THROCKMORTON COUNTIES WITH RADAR ESTIMATED TOTALS
BETWEEN 1.0 AND 1.5 INCHES IN THE PAST HOUR AS OF 0800Z. THIS NRN
AREA OF RAIN APPEARS TO BE TRANSLATING SLOWLY EAST HOWEVER WHILE
ADDITIONAL CONVECTIVE CELLS WERE EXPANDING IN COVERAGE EAST OF THE
RIO GRANDE...JUST WEST OF SAN ANTONIO...AS LARGE SCALE FORCING FOR
ASCENT INCREASES AHEAD OF THE APPROACHING TROUGH.

PERIODS OF TRAINING ARE EXPECTED TO INCREASE THROUGH 12Z ACROSS
CNTRL TEXAS...WITH FLASH FLOODING CERTAINLY A CONCERN WHERE
ANTECEDENT RAINFALL OVER THE PAST WEEK MAY NOT BE REPRESENTED VERY
WELL IN CURRENT FLASH FLOOD GUIDANCE VALUES OF 2.5 - 3.0 INCHES IN
3 HOURS. THE GREATER FLASH FLOOD CONCERN IS ACROSS THE SRN PORTION
OF THE MPD THREAT AREA WHERE BETTER ACCESS TO INSTABILITY AND
UPSLOPE ENHANCEMENT WILL BE IN PLACE OVER THE NEXT FEW HOURS. A
BROAD CONSENSUS OF MANY THE 00Z CAM GUIDANCE INCLUDES 6 HOUR
RAINFALL TOTALS OF 3-5 INCHES THROUGH 14Z.

OTTO

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

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

LAT...LON   33199748 32549661 30589689 29299772 28359913 
            28280026 29110066 30020029 31159972 32639891