MESOSCALE PRECIPITATION DISCUSSION 0864
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
341 PM EDT THU OCT 05 2017

AREAS AFFECTED...CENTRAL NM...WESTERN NORTH TX PANHANDLE...

CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY

VALID 051945Z - 060100Z

SUMMARY...ADDITIONAL BOUT OF THUNDERSTORMS WITH RAIN RATES UP TO
2"/HR AND SLOW CELL MOTIONS FALLING ACROSS COMPROMISED SOIL
CONDITIONS POSE POSSIBLE FLASH FLOODING CONCERNS THIS EVENING.

DISCUSSION...GOES-WV LOOP SHOWS FAIRLY LAMINAR AND DEEP SWLY FLOW
ACROSS THE FOUR CORNERS WITH BROAD CORE (90-100KT) OF 3H JET
ACROSS ACROSS THE CENTRAL CO ROCKIES LEAVING MUCH OF NEW MEXICO
WITHIN A WEAKLY DIFFLUENT AS RIGHT ENTRANCE REGION. VERY SIMILAR
ORIENTATION EXISTS WITH THE DEEP MOISTURE GRADIENT PER CIRA
LAYERED/TOTAL PW ANALYSIS RANGING FROM .75 IN THE NW CORNER TO 1.5
IN THE SE...WITH 1.25" TOTALS ON AVERAGE.  LOW LEVEL INFLOW
CONTINUES TO BE WEAK AT/BELOW 15-20KTS BUT SHOW SOME BACKING
RESPONSE TO WEAK HEIGHT FALLS/DAY TIME HEATING ON THE MOUNTAIN
RANGES.  THIS FLOW BECOMES INCREASINGLY CONFLUENT FURTHER INTO
CENTRAL NM AS WELL AS TURNING WITH ALTITUDE.  THIS SUGGESTS SOLID
MOISTURE CONVERGENCE AS WELL AS A GENERAL TRAINING SW TO NE
PROFILE AS CONVECTION PROPAGATES EASTWARD.

EFFECTIVE BULK SHEAR RANGES FROM 30KTS OVER CENTRAL NM TO 60KTS
ACROSS NW NM...POSING POTENTIAL FOR SUPERCELLULAR STRUCTURES
(REFER TO SPC MESO DISCUSSION 1690 FOR MORE DETAILS).  SUPERCELLS
WILL MAXIMIZE/STRENGTHENING MOISTURE FLUX/CONVERGENCE AS WELL AS
SLOW FORWARD PROGRESS...BOTH SUPPORTING INCREASED RAIN RATES AS
HIGH AS 2"/HR AND WITH 20-25KT FORWARD PROGRESS LEAD TO 1-2"
TOTALS.  THE CONCERN IS FOR FLANKING LINE DEVELOPMENT AND
POTENTIAL FOR ADDITIONAL UPSTREAM CELLS TO REGENERATE/TRACK ACROSS
SIMILAR PATHS SUPPORTING THE THREAT FOR ISOLATED AREAS OF 2-3" AS
SUGGESTED BY RECENT HRRRV3 SOLUTIONS.  

IRRESPECTIVE OF CELL MODE...HRRR/HRRRV3 SOIL TOP CM SATURATION
VALUES ARE WELL OVER 80% ACROSS THE DISCUSSION REGION WITH SOME
100% AREAS ALREADY DUE TO PRIOR TWO DAYS OF HEAVY RAINFALL (MAINLY
OVER GUADELUPE/QUAY/SAN MIGUEL/SE HARDING LEAKING INTO THE WESTERN
TX PANHANDLE OLDHAM/HARTLEY COUNTIES).  OBVIOUSLY THIS IS THE
GREATEST THREAT AREA FOR FLASH FLOODING AND ANY CELLS CAPABLE OF
RATES OF 1.5-2"/HR AND TOTALS OVER 1" ARE LIKELY TO TRIGGER
ADDITIONAL RUNOFF/FLASH FLOODING CONCERNS.  WHILE CURRENT COVERAGE
IS LIMITED...INSTABILITY/MOISTURE/LIFT IS SUFFICIENT ACROSS THIS
AREA THIS EVENING IN LOCALIZED AREAS TO CONSIDERED FLASH FLOODING
LIKELY...THOUGH PLACES THAT HAVE NOT SEEN COMPROMISED SOILS MAINLY
FURTHER WEST...FF RISK IS ONLY POSSIBLE AND EVEN MORE ISOLATED IN
AREAL EXTENT. 

GALLINA

ATTN...WFO...ABQ...AMA...

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

LAT...LON   36250309 36160215 35700215 34830349 34520460
            34380679 34330755 34690807 35280798 35500620
            36230425