Flash Flood Guidance
Issued by NWS

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000
AWUS01 KWNH 061742
FFGMPD
TXZ000-OKZ000-NMZ000-062341-

MESOSCALE PRECIPITATION DISCUSSION 0313
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
141 PM EDT MON JUL 06 2015

AREAS AFFECTED...NORTHEAST NM & THE TX PANHANDLE

CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE

VALID 061741Z - 062341Z

SUMMARY...FORMING THUNDERSTORMS WITH HEAVY RAINFALL ARE EXPECTED
TO ORGANIZE AND DEVELOP FURTHER THIS AFTERNOON.  HOURLY RAIN RATES
UP TO 1.5" COULD LEAD TO FLASH FLOODING.

DISCUSSION...A COLD FRONT HAS BEEN SLIDING THROUGH THE SOUTHERN
HIGH PLAINS THIS MORNING, WITH UPSLOPE FLOW INTO NORTHEAST NM SEEN
IN ITS WAKE.  PRECIPITABLE WATER VALUES IN THE REGION ARE
1.25-1.5" PER GPS INFORMATION, OVER TWO SIGMAS ABOVE THE NORM FOR
EARLY JULY.  MLCAPES ACROSS NORTHERN TX ARE IN THE 1000-3000 J/KG
RANGE, WITH 500-1000 MLCAPE BUILDING ACROSS NORTHEAST NM.  CIN
CONTINUES TO FADE PER TRENDS FROM THE SPC MESOANALYSIS PAGE.

THE EXPECTATION (PER RECENT RAP RUNS) IS FOR INSTABILITY TO CLIMB
ACROSS NORTHEAST NM, EXCEEDING 1000 J/KG BY 19Z AS UPSLOPE FLOW
INCREASES TO 20-25 KTS FROM THE NORTHEAST.  PRECIPITABLE WATER
VALUES ARE PROGGED TO INCREASE INTO THE 1.5-1.75" RANGE ACROSS
NORTHEAST NM, THREE SIGMAS ABOVE THE EARLY JULY MEAN, BY 00Z.  A
SHORTWAVE MOVING ACROSS WESTERN AND CENTRAL NM IS EXPECTED TO LEAD
TO A 3-5C 700 HPA TEMPERATURE FALL, WHICH SHOULD ELIMINATE ANY
REMNANT CAPPING.  CONVECTION SHOULD INITIALLY MOVE GENERALLY EAST
AT 5-10 KTS PER THE MEAN 850-400 HPA WIND, WHICH TOGETHER WITH THE
LOW-LEVEL INFLOW MAGNITUDE/DIRECTION SHOULD LEAD TO CONVECTIVE
ORGANIZATION/25-35 KTS OF CLOUD BASE INFLOW.

ORGANIZED STORMS ARE EXPECTED TO MOVE EAST-NORTHEAST AT 15-20 KTS
PER FORWARD PROPAGATING CORFIDI VECTORS DUE TO THE DIRECTIONAL
WIND SHEAR PRESENT AND SOME DRY AIR INITIALLY IN LOW LEVELS.  THIS
MOTION WOULD LEAD TO BOTH CELL TRAINING NEAR AND BEHIND THE FRONT
AND FURTHER ORGANIZE CONVECTIVE CELLS.  THE EXPECTED MOISTURE
SHOULD LEAD TO HOURLY RAIN RATES UP TO 1.5", ROUGHLY EQUIVALENT TO
THE THREE HOUR FLASH FLOOD GUIDANCE VALUES.  THE MESOSCALE
GUIDANCE ADVERTISES LOCAL AMOUNTS OF 2-3" ACROSS THE AREA WHICH
COULD FALL QUICKLY.  THE 06Z SSEO NEIGHBORHOOD PROBABILITIES
EXCEED 50% BY 19Z, AND PEAK AT 90%+ ACROSS NORTHEAST NM BY 23Z,
WITH 50%+ PROBABILITIES EXTENDING ACROSS THE TX PANHANDLE BY 00Z.
THE REGION HAS EXPERIENCED 3-6" OF RAIN OVER THE PAST 30 DAYS,
ABOVE NORMAL FOR JUNE/JULY.  FLASH FLOODING IS CONSIDERED POSSIBLE.

ROTH

...PLEASE SEE WWW.WPC.NCEP.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...ABQ...AMA...LUB...OUN...

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

LAT...LON   36879934 35789920 34610009 34150141 34050349
            34150458 34330548 34620644 35380650 35990632
            36070449 36210147


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