FXUS64 KMAF 160527
AFDMAF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIDLAND/ODESSA TX
1127 PM CST TUE DEC 15 2009

.DISCUSSION...
SEE AVIATION DISCUSSION BELOW.

&&

.AVIATION...
POST FRONTAL CONDITIONS WITH MOSTLY CLEAR SKIES AND LIGHT WIND 
TONIGHT.  MAY SEE A HINT OF LOW CLOUDS AT CNM.  WIND SHOULD VEER 
AROUND TO THE SOUTH TOMORROW AS LEESIDE TROUGH DEEPENS. 

&&

.PREV DISCUSSION... /ISSUED 848 PM CST TUE DEC 15 2009/ 

UPDATE...
SEE DISCUSSION BELOW.

DISCUSSION...
WILL UPDATE TO LOWER LOW TEMPERATURES TONIGHT MAINLY ACROSS THE
PERMIAN BASIN AND LEA COUNTY NEW MEXICO BASED ON LATEST
TEMPERATURE AND DEW POINT TRENDS AND INCOMING GUIDANCE. ALSO
TWEAKED SKY AND DEW POINT GRID. 

UPDATED PRODUCTS TO BE SENT SHORTLY.

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PREV DISCUSSION... /ISSUED 148 PM CST TUE DEC 15 2009/

DISCUSSION...
A SHORTWAVE TROUGH WAS TRANSLATING SLOWLY EASTWARD OVER THE FORECAST 
AREA THIS AFTERNOON...WHILE THE SOUTHWESTERN FRINGE OF AN ARCTIC  
AIRMASS NOSED INTO THE REGION.  DESPITE THE PRESENCE OF THE UPPER 
TROUGH...CLOUD COVER WAS PRETTY SPARSE EXCEPT OVER PORTIONS OF THE 
STOCKTON PLATEAU...BIG BEND AND LOWER TRANS PECOS.  A WEAK CUTOFF 
LOW ALONG THE RIO GRANDE/BIG BEND REGION WILL RESULT FROM THE UPPER 
TROUGH TONIGHT.  THIS FEATURE WILL MOVE SLOWLY EASTWARD AND REACH 
CENTRAL TEXAS BY THURSDAY.  NOT EXPECTING ANY PRECIPITATION WITH 
THIS FEATURE...NOR MUCH CLOUD COVER EITHER.  SINCE GOOD RADIATIONAL 
COOLING CONDITIONS WILL EXIST OVER THE AREA...EXCEPT FOR SOME CLOUD 
COVER OVER THE LOWER TRANS PECOS AND BIG BEND...WILL UNDERCUT MOS 
GUIDANCE FOR LOWS TONIGHT.  

THE SURFACE RIDGE WILL CLING TO THE REGION WEDNESDAY...WITH A LEE 
TROUGH DEVELOPING/STAYING NORTH AND WEST OF THE REGION.  HAVE GONE 
CLOSER TO MOS GUIDANCE WEDNESDAY AFTERNOON...SINCE THERE WILL BE 
PLENTY OF SUN AND HOW MUCH INFLUENCE THE SURFACE RIDGE HAS OVER THE 
AREA IS NOT CLEAR.  ANOTHER CHILLY MORNING EXPECTED THURSDAY AS GOOD 
RADIATIONAL COOLING CONDITIONS WILL EXIST MOST AREAS AGAIN.  
TEMPERATURES WILL WARM ABOVE NORMAL THURSDAY AS THE FLOW ALOFT 
INCREASES...A SURFACE TROUGH DEVELOPS OVER THE AREA AND THE HEART OF 
THE ARCTIC AIRMASS OVER THE CENTRAL PLAINS WILL HAVE MOVED TO THE 
EASTERN SEABOARD.  THE SPEED OF THE NEXT SHORTWAVE TROUGH WILL 
DETERMINE HOW MUCH CLOUD COVER ENDS UP OVER THE REGION THURSDAY 
AFTERNOON...WHICH COULD TEMPER THE WARMUP.  SINCE AT LEAST MODEST 
DOWNSLOPE WINDS COULD AFFECT MOST AREAS...WILL TEND MORE TOWARD THE 
RELATIVELY WARM MOS NUMBERS.  

THE FLOW ALOFT WILL BE AMPLIFYING OVER THE U.S. PLAINS LATE THIS 
WEEK...AND WILL BE ACCOMPANIED BY ANOTHER COLD FRONT.  THIS NEXT 
FRONT WILL MOVE THROUGH ALL OF WEST TEXAS FRIDAY NIGHT...SO SOME 
LOCATIONS OVER SOUTHWEST TEXAS MAY WARM INTO THE 70S DURING THE DAY 
FRIDAY.  ALTHOUGH INDICATIONS ARE THE AIRMASS BEHIND THE WILL BE 
INTERMINGLED WITH MORE OF A MARITIME POLAR AIRMASS...LOWER HEIGHTS 
AND THICKNESSES AND CLOUD COVER WILL KEEP TEMPERATURES 5 TO 10 
DEGREES BELOW NORMAL SATURDAY.  THERE APPEARS TO BE A BRIEF WARMUP 
SUNDAY UNDER NORTHWEST FLOW ALOFT BEFORE A STRONGER COLD FRONT MOVES 
INTO THE AREA MONDAY.  IT APPEARS THIS FRONT WILL REALLY BE DRIVEN 
SOUTHWARD WITH THE COLD AIR LASTING OVER THE REGION THROUGH MIDWEEK 
AS A SERIES OF SHORTWAVE TROUGHS WHEEL AROUND A STRONG UPPER LOW 
PROGGED TO TAKE UP TEMPORARY RESIDENCE OVER THE MIDWEST NEXT WEEK.  
THEREFORE...HAVE CONTINUED THE TREND OF UNDERCUTTING GUIDANCE 
TEMPERATURES MOST PERIODS THROUGH THE EXTENDED.  WILL LEAVE THE 
EXTENDED FORECAST DRY SINCE IT APPEARS THERE WILL NOT BE MUCH ROOM 
FOR ANY MOISTURE TO MOVE INTO THE AREA...ASIDE FROM SOME MID AND 
UPPER LEVEL MOISTURE FROM PASSING SHORTWAVE TROUGHS.  

&&

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

&&

$$

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