MESOSCALE PRECIPITATION DISCUSSION 0598
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1211 PM EDT THU OCT 22 2015
AREAS AFFECTED...WEST TEXAS...NORTH CENTRAL TX
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY
VALID 221611Z - 222011Z
SUMMARY...EXPECT CONVECTION TO CONTINUE TO TRAIN SOUTHWEST TO
NORTHEAST ALONG A QUASI-STATIONARY SURFACE BOUNDARY...WITH
ADDITIONAL REDEVELOPMENT FORECAST ALONG THE SOUTHERN FLANK OF THE
BOUNDARY. LOCAL RAINFALL RATES OF 1-2 INCHES/HR ARE LIKELY TO
PRODUCE ADDITIONAL FLASH FLOODING ACROSS PORTIONS OF THE REGION.
DISCUSSION...NOT MUCH CHANGE FROM THE PREVIOUS ISSUANCE. A
QUASI-STATIONARY SURFACE BOUNDARY REMAINS IN PLACE FROM THE
WESTERN RED RIVER BACK INTO THE BIG BEND COUNTRY. THE LATEST
MESOANALYSIS SHOWS THAT 30-40 KT SOUTHEASTERLY TO SOUTHERLY FLOW
CONTINUES TO SUPPORT 1.5+ INCH PWS ALONG AND AHEAD OF MUCH OF THE
BOUNDARY WHILE 1000+ J/KG MUCAPE VALUES CONTINUE TO EXTEND
NORTHEAST FROM THE BIG BEND COUNTRY INTO CENTRAL TX. A
SOUTHWEST-NORTHEAST ORIENTED UPPER JET STREAK POSITIONED TO THE
EAST OF AN UPPER LOW CENTERED OVER THE FOUR-CORNERS REGION
CONTINUES TO ENHANCE THE UPPER DIVERGENCE ACROSS THE REGION.
SPLITTING FLOW UPSTREAM IS EXPECTED TO ALLOW THIS LOW TO REMAIN IN
PLACE...WITH NO SIGNIFICANT CHANGE IN THE UPPER LEVEL PATTERN
ANTICIPATED ACROSS THE REGION FOR AT LEAST THE NEXT FEW HOURS.
BELIEVE THE GREATEST POTENTIAL FOR HEAVY RAINFALL RATES REMAINS
COINCIDENT WITH THE GREATER INSTABILITY ALONG THE SOUTHERN FLANK
OF THE BOUNDARY. HOWEVER...CONVECTION TRAINING TO THE NORTH MAY
EXTEND THE FLASH FLOOD THREAT FURTHER TO NORTHEAST ACROSS
NORTH-CENTRAL TX INTO THE RED RIVER REGION.
THE LATEST OUTLOOK AREA WAS AGAIN BASED LARGELY ON AMOUNTS
PRODUCED BY THE 00Z HRW-NMMB -- WHICH OF THE HI-RES
GUIDANCE...APPEARS TO THE HAVE ONE THE BETTER HANDLES ON THE
CURRENT CONDITIONS. THE 00Z HRW-ARW IS TOO PROGRESSIVE...WHILE
EVEN THE MOST RECENT RUNS OF THE HRRR ARE MUCH TOO DRY ACROSS
CENTRAL TX INTO THE BIG BEND COUNTRY.
PEREIRA
ATTN...WFO...FWD...LUB...MAF...OUN...SJT...
ATTN...RFC...ABRFC...WGRFC...
LAT...LON 34159836 33589806 32619838 31989976 30850088
30240210 30790216 31790142 32600054 33709936