Flash Flood Guidance
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000
AWUS01 KWNH 071226
FFGMPD
TXZ000-OKZ000-071655-

MESOSCALE PRECIPITATION DISCUSSION 0321
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
826 AM EDT TUE JUL 07 2015

AREAS AFFECTED...CENTRAL TO NORTHERN TX/EXTREME SOUTH-CENTRAL
OK...

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

VALID 071225Z - 071655Z

SUMMARY...ALTHOUGH THE AREAL EXTENT OF COLDER TOPS HAVE DIMINISHED
IN RECENT SATELLITE IMAGERY...HOURLY RAINFALL RATES HAVE REMAINED
IN THE 1 TO 2 INCH RANGE. EXPECT A THREAT FOR FLASH FLOODING TO
EXIST...PARTICULARLY IN REGIONS OF REPEAT/SLOW-MOVING CONVECTION.

DISCUSSION...A MESOSCALE CONVECTION COMPLEX WHICH MOVED ACROSS
WEST TX DURING THE OVERNIGHT HOURS HAS GENERALLY REMAINED INTACT
THROUGH 12Z. IR-SATELLITE TOPS INDICATES GENERAL WARMING ALTHOUGH
A SUBTLE REGION OF COOLING IS NOTED ALONG THE LEADING CONVECTIVE
LINE. RATHER BUOYANT AIR CURRENTLY RESIDES DOWNSTREAM IN THE
WARM/MOIST SECTOR WHICH HAS FUELED ADDITIONAL CONVECTION IN THE
SAN ANGELO CWA. THE 11Z RAP ANALYSIS SHOWS MUCAPE VALUES IN THE
1000 TO 2000 J/KG RANGE THUS SUPPORTING THIS DEVELOPING CONVECTION.

THIS SYSTEM DOES HAVE A HISTORY OF PRODUCING VERY HEAVY RAINFALL
WITH HOURLY RATES APPROACHING 2 INCHES. WHILE THIS SHOULD OCCUR ON
A MORE LOCALIZED BASIS...THERE SHOULD STILL BE AN INHERENT RISK
FOR FLASH FLOODING DURING THE MORNING HOURS.

LOOKING AT THE HIGH-RESOLUTION GUIDANCE...IT APPEARS A MAJORITY OF
THEIR SOLUTIONS ARE TOO FAR NORTH WHICH SEEMS TO BE DUE TO THE
POSITION OF THE MID/UPPER VORTICITY MAXIMA. WHILE THE PLACEMENT
LOOKS OFF...THE AMOUNTS SEEM REASONABLE WITH THE ACTIVITY RAMPING
UP AS DAYTIME HEATING COMMENCES. FOR FURTHER INFORMATION ON THIS
SYSTEM...PLEASE CHECK OUT THE SPE ISSUED FROM NESDIS.


RUBIN-OSTER

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

ATTN...WFO...FWD...LUB...MAF...OUN...SJT...

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

LAT...LON   34839875 34509758 33409705 31469814 30659935
            30590109 31420175 32380062 34259963


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