MESOSCALE PRECIPITATION DISCUSSION 0548
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
627 PM EDT SAT OCT 03 2015
 
AREAS AFFECTED...PORTIONS OF SOUTHEAST NM/WESTERN TX 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 032226Z - 040256Z
 
SUMMARY...THUNDERSTORMS NEAR AND AROUND EL PASO ARE EXPECTED TO
EXPAND IN COVERAGE TO THE EAST/EAST-SOUTHEAST WITH TIME.  HOURLY
RAIN RATES UP TO 1.5" COULD LEAD TO FLASH FLOODING.

DISCUSSION...A GROWING AREA OF SCATTERED THUNDERSTORMS IS
CONGEALING NEAR EL PASO TX IN THE VICINITY OF A THERMAL GRADIENT. 
PRECIPITABLE WATER VALUES OF ~1.25" LIE ACROSS THE REGION, CLOSE
TO 1.5 SIGMAS ABOVE EARLY OCTOBER NORMS.  MUCAPE IN THE REGION IS
1000-2000 J/KG, WHILE INFLOW AT 850 HPA IS ~20 KTS.  CLOUD TOPS
ARE BEGINNING TO COOL IN THIS REGION, INDICATIVE OF THE UPWARD
TREND IN CONVECTIVE GROWTH.  MOISTURE ALOFT IS MOVING IN FROM A
PACIFIC CONVECTIVE DISTURBANCE OFF THE COAST OF WESTERN MEXICO,
WHICH IS HELPING TO SATURATE THE MID- TO UPPER-LEVELS OF THE
TROPOSPHERE.

THE EXPECTATION IS FOR THE LOW-LEVEL INFLOW TO INCREASE ANOTHER 10
KTS OR SO, WHICH WOULD EXCEED THE MEAN 850-400 HPA WINDS BY 5-10
KTS, INCREASING RAINFALL EFFICIENCY.  THIS INCREASE IN INFLOW
SHOULD HELP ELEVATE CONVECTION FROM A PULSE INTO A MORE ORGANIZED
MODE.  PRECIPITABLE WATER VALUES ARE EXPECTED TO BREACH 1.50" AS
WELL.  WHILE FORWARD PROPAGATING CONVECTIVE VECTORS SUGGEST
ORGANIZED CONVECTION SHOULD MOVE EAST-NORTHEAST AT 25-30 KTS, THE
1000-500 HPA THICKNESS PATTERN SUGGESTS ANY ORGANIZED SYSTEM
SHOULD MOVE EAST TO EAST-SOUTHEAST.  THE CAM GUIDANCE ADVERTISES
LOCAL AMOUNTS AROUND 2", WHICH COULD FALL QUICKLY, AS AVAILABLE
MOISTURE SUPPORTS HOURLY RAIN RATES UP TO 1.5".  BELIEVE THE 12Z
SPC WRF HAS CAPTURED THE CONVECTIVE POTENTIAL THE BEST -- MOST OF
THE OTHER CAM GUIDANCE APPEARS TOO FAR NORTH WITH THEIR PLACEMENT.
 FLASH FLOODING IS CONSIDERED POSSIBLE.

ROTH

ATTN...WFO...EPZ...MAF...

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

LAT...LON   32510548 32270328 30960365 30880579 31450728 
            32090706