MESOSCALE PRECIPITATION DISCUSSION 0051
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
536 AM EST TUE MAR 08 2016
 
AREAS AFFECTED...CENTRAL AND NORTHERN TX...SOUTHERN OK 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 081025Z - 081500Z
 
SUMMARY...RAPIDLY EXPANDING CONVECTION OVER THE TX HILL COUNTRY
WILL FOSTER SOME CONCERNS FOR RUNOFF PROBLEMS AND POSSIBLE FLASH
FLOODING THIS MORNING.

DISCUSSION...COOLING CONVECTIVE TOPS ARE EXPANDING IN COVERAGE
THIS MORNING ACROSS THE TX HILL COUNTRY AS SHORTWAVE ENERGY AND
STRONGLY DIVERGENT FLOW ALOFT EJECTS OUT ACROSS WEST TEXAS AND
INTERACTS WITH A FAVORABLY MOIST AND UNSTABLE AIRMASS THAT HAS
POOLED NORTHWARD WITH THE HELP OF A SOUTHERLY LOW LEVEL JET OF 40
TO 45 KTS AS PER AREA VWP DATA.

PWATS AS PER GPS DATA AS RUNNING BETWEEN 1 AND 1.3 INCHES FROM THE
TX HILL COUNTRY NORTHEAST TO THE RED RIVER VALLEY. MEANWHILE...RAP
DATA INDICATES A POOL OF MODERATE INSTABILITY OVER WEST-CENTRAL
TX...WITH MUCAPE REACHING OVER 2000 J/KG...AND OWING IN PART TO
STEEP 500/700 MB LAPSE RATES OF NEARLY 8 DEG C/KM.

OVER THE NEXT SEVERAL HOURS...STRONGER DEEP LAYER ASCENT WILL
CONTINUE TO TAKE ADVANTAGE OF A STRONGER THERMODYNAMIC ENVIRONMENT
TO SUSTAIN THE CURRENT LEVEL OF CONVECTIVE ORGANIZATION WITH
PERHAPS SOME ADDITIONAL EXPANSION IN COVERAGE AS THE ACTIVITY
LIFTS NORTHEAST GRADUALLY TOWARD THE RED RIVER VALLEY. MULTIPLE
RUNS OF THE HRRR AND ALSO THE 00Z ARW/00Z NMMB GUIDANCE SUGGEST
THE CONVECTIVE ORIENTATION POSSIBLY BECOMING MORE ALIGNED WITH THE
DEEPER LAYER MEAN FLOW IN A SW/NE FASHION AFTER 12Z...AND THIS
WILL SUPPORT SOME INCREASING RISK OF TRAINING CONVECTION.

SOME AREAS IN THE PATH OF THE CONVECTION ALREADY SAW HEAVY RAINS
LAST EVENING AND THUS FFG VALUES ARE MUCH LOWER ACROSS THESE
AREAS. THE WET ANTECEDENT CONDITIONS COUPLED WITH HEAVY RAINFALL
RATES OF 1.5 INCHES/HR WITH THE NEXT BATCH OF CONVECTION WILL
ENHANCE THE THREAT FOR ADDITIONAL FLASH FLOODING AND RUNOFF
PROBLEMS THIS MORNING. WILL CONTINUE TO MONITOR.

ORRISON

ATTN...WFO...EWX...FWD...OUN...SJT...

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

LAT...LON   34699727 34669646 34289614 33909608 33299636 
            32609697 31489817 30729907 30359966 30180026 
            30330064 30590064 31250003 31859979 32359977 
            33029945 33939847