Flash Flood Watch 5, NWS Midland/Odessa, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIDLAND/ODESSA TX
643 PM CDT THU AUG 21 2008

.DISCUSSION...
SEE AVIATION DISCUSSION BELOW.

&&

.AVIATION...
VFR CONDITIONS ARE EXPECTED THE NEXT 24 HOURS. SOUTH TO SOUTHEAST
WINDS OF 10 KNOTS OR LESS ARE GENERALLY EXPECTED OVERNIGHT. ONE
EXCEPTION IS AT FORT STOCKTON WHERE SOUTH WINDS WILL BRIEFLY
GUST TO 35 MPH THROUGH 01Z...ASSOCIATED WITH THE REMNANTS OF
THUNDERSTORMS. WINDS WILL BE GUSTY AT TIMES FRIDAY...GUSTING TO 20
TO 25 MPH AT SEVERAL OF THE TERMINALS. SOME SCATTERED CIRRUS
CLOUDS EXPECTED OVERNIGHT WITH SOME CUMULUS BY FRIDAY AFTERNOON.

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&&

.PREV DISCUSSION... /ISSUED 255 PM CDT THU AUG 21 2008/

DISCUSSION...

CONVECTION BEGINNING TO DEVELOP ACROSS THE BIG BEND AND WEST TEXAS
MOUNTAINS AREAS THIS AFTERNOON ALL IN RESPONSE TO A SMALL UPPER
LEVEL LOW PRESSURE CENTER LOCATED ACROSS THE RIO GRANDE VALLEY. AM
EXPECTING TRENDS TO CONTINUE THROUGH THE EARLY EVENING IN RESPONSE
TO PEAK HEATING AND AVAILABLE INSTABILITY. ADDITIONAL FOCUS FOR
POTENTIAL DEVELOPMENT FURTHER NORTH ACROSS THE GUADALUPE MOUNTAINS
AND SOUTHEAST NEW MEXICO PLAINS MAY RESIDE WITH A WELL DEFINED
LEE SIDE TROUGH WHICH REMAINS ANCHORED ACROSS THE HIGH PLAINS OF NW
MEXICO. ADDITIONALLY...WRF SOLUTIONS ALSO DEPICTING THE ARRIVAL
OF AN UPPER LEVEL SHORTWAVE TROUGH FROM THE FOUR CORNERS
REGION...ALSO LEADING TO POTENTIAL FURTHER DEVELOPMENT. WITH THESE
FACTORS IN PLACE...DECIDED TO KEEP SLIGHT CHANCE TO CHANCE POPS
GOING FOR AREAS WEST AND SOUTH OF KMAF AREA. NOT OVERLY CONCERNED
WITH SEVERE WEATHER POTENTIAL THIS AFTERNOON AS 0-6KM BULK SHEAR
WILL LIKELY REMAIN LESS THAN 20KTS IN RESPONSE TO RATHER WEAK MID-
LEVEL FLOW.

FORECAST FOR THE NEXT SEVERAL DAYS IS BY NO MEANS AN EASY ONE AS
WEST TEXAS AND THE PLAINS OF SE NEW MEXICO WILL LITERALLY LIE
BETWEEN SEVERAL WEATHER SYSTEMS. OFF TOWARDS THE NORTHEAST...THE
PERSISTENT UPPER LEVEL LOW PRESSURE CENTER RESPONSIBLE FOR THIS
PAST WEEKEND/S RAIN WILL ONLY SLOWLY BEGIN TO ENTER THE MID MISS
RVR VLY. OFF TOWARDS THE NORTHWEST...A BUILDING RIDGE OF HIGH
PRESSURE WILL RESIDE OVER THE SOUTHWEST...BEFORE EXTENDING INTO
THE FOUR CORNERS REGION. TOWARDS THE SOUTHWEST...THE CUT-OFF LOW
RESPONSIBLE FOR THIS AFTERNOON/S CONVECTION IS EXPECTED TO REMAIN
IN PLACE THROUGH PORTIONS OF THE UPCOMING WEEKEND...WHILE THE
REMNANTS OF TS FAY WILL SLOWLY BEGIN MOVING WESTWARD WITH TIME.
WITH THAT BEING SAID...REGION HAS THE POTENTIAL OF BEING IMPACTED
BY SEVERAL WEATHER MAKERS IN THE COMING DAYS.

FRIDAY APPEARS TO BE THE WARMEST DAY ON TAP FOR THE REGION AS LOW
CLOUDS AND PRECIP CHANCES WILL REMAIN CONFINED TO MAINLY THE
MOUNTAINOUS REGIONS OF WEST TEXAS. ALL SHORT TERM PROGS ARE IN
RATHER GOOD AGREEMENT WITH BROAD SOUTHERLY TO SOUTHEASTERLY FLOW
BY TOMORROW AFTERNOON...HELPING TO KEEP TEMPS IN THE NORMAL TO
SLIGHTLY ABOVE NORMAL CATEGORY. VERY UNCLEAR ON THE AMOUNT OF
MOISTURE AVAILABLE FOR PREVIOUSLY DISCUSSED UPPER LOW ACROSS THE
RIO GRANDE VALLEY...HOWEVER FEEL CONFIDENT THAT WITH THIS FEATURE
IN PLACE...POTENTIAL STEEPENING OF LOW AND MID LEVEL LAPSE RATES
WILL LIKELY RESULT IN CONVECTION OVER THE MOUNTAINS ONCE AGAIN.
BASED ON ABOVE REASONING...DECIDED TO KEEP SLIGHT CHANCE POPS
GOING FOR AREAS WEST OF THE TRANS PECOS AREA THROUGH THE DAY
TOMORROW.

RATHER NOTICEABLE COOLING POSSIBLE ONCE AGAIN THIS WEEKEND AS
PRECIP CHANCES AND LOW LEVEL CLOUDINESS APPEAR ON THE HORIZON FROM
THE SOUTHEAST. GFS SOLUTIONS BEGINNING TO HINT AT POTENTIAL SFC
CYCLOGENESIS ACROSS THE LOWER RIO GRANDE VALLEY BY SAT...WHICH
WOULD RESULT IN INCREASED MOISTURE ADVOCATION INTO OUR AREA. ECMWF
SOLUTIONS ALSO BEGINNING TO HINT TOWARDS THIS SCENARIO AS
WELL...WHICH HELPS LEAD A BIT MORE CONFIDENCE TO GOING FORECAST.
BASED ON THIS AND THE POTENTIAL FOR SCATTERED SHOWERS/STORMS
ACROSS THE REGION THROUGH THE WEEKEND...DECIDED TO TRIM TEMPS A
BIT WHILE AT THE SAME TIME INCREASING POPS ACROSS THE SOUTH AND
EAST. OBVIOUSLY A HIGH BUST POTENTIAL FOR HIGH TEMPS BUT
CONFIDENCE IS INCREASING BASED ON MODEL AGREEMENT THROUGH THE
PERIOD. ADDI TONALLY...A WELL DEFINED SHEAR AXIS (DEFORMATION
AXIS) WILL LIKELY RESIDE SOMEWHERE CLOSE TO THE REGION AS THE AREA
WILL REMAIN ANCHORED BETWEEN SEVERAL DIFFERENT SYSTEMS. WITH THIS
IN PLACE...ADDITIONAL FOCUS WILL BE PRESENT FOR POTENTIAL PRECIP
ACROSS THE REGION. IT CURRENTLY APPEARS THAT THE BEST CHANCES WILL
RESIDE FROM THE BIG BEND AREA...NORTHEASTWARD THROUGH PORTIONS OF
THE PERMIAN BASIN. AS THE EVENT DRAWS NEAR...HOPEFULLY THE FINER
DETAILS CAN BE ESTABLISHED AND THE APPROPRIATE CHANCES BE MADE.

PRECIP CHANCES LIKELY EXTENDING INTO EARLY PORTIONS OF NEXT WEEK
BEFORE UPPER LEVEL RIDGE FINALLY SENDS LOW ON ITS WAY BY MIDWEEK.
TEMPS THROUGH THE BEGINNING OF THE WORK WEEK WILL LIKELY REMAIN
BELOW AVERAGE AS A RESULT WITH GRADUAL WARMING EXPECTED MY MID
AND LATE NEXT WEEK.

&&

.MAF WATCHES/WARNINGS/ADVISORIES...
NM...NONE.
TX...NONE.

&&

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