MESOSCALE PRECIPITATION DISCUSSION 0389
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
111 PM EDT THU SEP 18 2014
 
AREAS AFFECTED...SRN NM...FAR SW TX 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY 
 
VALID 181710Z - 182210Z
 
SUMMARY...THE RISK OF FLASH FLOODING IS FORECAST TO INCREASE THIS
AFTERNOON. SYNOPTIC FEATURES WILL LIFT A TROPICAL AIR MASS TO FORM
EMBEDDED CONVECTION IN SOUTHERN NM. HEATING ELSEWHERE WILL LEAD TO
INCREASINGLY ROBUST SURFACE-BASED CONVECTION IN SE NM AND SW TX.

DISCUSSION...THE SIGNAL IN THE HIGH RESOLUTION MODEL QPF IS NOT
VERY FOCUSED...BUT THE ENVIRONMENT APPEARS SUPPORTIVE OF AN
INCREASED FLASH FLOOD THREAT THIS AFTERNOON. THE REMNANT
CIRCULATION ASSOCIATED WITH ODILE WILL TRACK TOWARD SOUTHERN
NM...WHERE THE RAP INDICATES MAINTENANCE OF A SHARP 700 MB TROUGH
BENEATH DIFLUENT UPPER LEVEL FLOW. RAP FORECAST SOUNDINGS MAINTAIN
A VERY SATURATED LOW TO MID LEVEL PROFILE THROUGH THE AFTERNOON.
WITH PRECIPITABLE WATER VALUES AT 3 STANDARD DEVIATIONS FROM
CLIMATOLOGY...EMBEDDED LOW-TOPPED CONVECTION WILL PRODUCE
EFFICIENT RAINFALL...SUCH AS NOTED IN A RECENT 1.5"/2 HOUR
OBSERVATION AT CHAPARRAL NM.

MEANWHILE...INSTABILITY WILL INCREASE FARTHER EAST INTO SE NM AND
SW TX. THE MOUNTAINOUS TERRAIN IN TX AND PRESENCE OF DIFFERENTIAL
HEATING BOUNDARIES ARE LIKELY TO SPUR DEVELOPMENT OF
CONVECTION...WHICH MAY TEND TO ORGANIZE OWING TO WIDESPREAD
INSTABILITY AND INCREASING EASTERLY INFLOW BY LATE AFTERNOON.
AGAIN...THE MODEL SIGNAL IS NOT STRONG...BUT THE LATEST NAM
CONEST...WRF ARW...AND 15Z HRRR SUGGEST SMALL SCALE AREAS OF 1-2
INCH RAINS WILL BE COMMON. LOCALLY HIGHER AMOUNTS ARE POSSIBLE IN
SE NM/SW TX BEFORE COLD POOLS BEGIN TO ACCELERATE THE CONVECTION.

BURKE

ATTN...WFO...ABQ...EPZ...LUB...MAF...

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

LAT...LON   33830536 33740369 32920283 31720245 30860243 
            30110298 30310415 31030523 31090705 31180856 
            31990888 32950830 33620677