FXUS64 KMAF 261728
AFDMAF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIDLAND/ODESSA TX
1128 AM CST SAT DEC 26 2009

.DISCUSSION...
SEE AVIATION DISCUSSION BELOW.

&&

.AVIATION...
LIGHT WINDS AND CLEAR SKIES THROUGH THE TAF PERIOD WILL PROVIDE
EXCELLENT AVIATION CONDITIONS.

HENNIG

&&

.PREV DISCUSSION... /ISSUED 343 AM CST SAT DEC 26 2009/ 

DISCUSSION...
ON WATER VAPOR AN UPPER/MID LEVEL LOW PRESSURE CAN BE SEEN CENTERED 
OVER MID-WESTERN STATES. GOOD MODEL AGREEMENT BETWEEN THE NAM...GFS 
AND ECMFW SHOW THAT THIS LOW WILL DRIFT SLOWLY TOWARDS THE GREAT 
LAKES AND THEN MOVE OFF THE EAST COAST BY MONDAY EVENING. WHILE IT 
REMAINS OVER THE CENTRAL AND NORTHEASTERN U.S. IT WILL KEEP BRINGING 
ARCTIC AIR DOWN THE CENTRAL U.S. AND INTO THE CWA. THE SURFACE 
RIDGING...AND NORTHERLY SURFACE WINDS THAT ARE CURRENTLY OVER WEST 
TEXAS AND SOUTHEASTERN NEW MEXICO ARE EXPECTED TO REMAIN FOR THE 
NEXT SEVERAL DAYS...AS THE UPPER LEVEL PATTERN SHOWS SLOW MOVEMENT.
AS A RESULT THE TEMPERATURES OVER THE CWA WILL BE MUCH COLDER THAN
NORMAL FOR THE NEXT SEVERAL DAYS. BY TUESDAY A SOUTHWEST FLOW
ALOFT WILL PRECEDE THE NEXT APPROACHING UPPER/MID LEVEL TROUGH.
THE LIFT AHEAD OF THIS TROUGH WILL BEGIN TO IMPACT THE WEATHER OF
THE CWA AS EARLY AS MONDAY AFTERNOON. THE NAM BRINGS IN SOME SMALL
QPF AMOUNTS BEFORE 00Z TUESDAY.

MONDAY NIGHT AND TUESDAY DURING THE DAY HAVE THE BEST CHANCE OF 
PRECIPITATION WITH THIS UPPER/MID LEVEL TROUGH. UPPER LEVEL SUPPORT 
IS EVIDENT...THE ECMWF SHOWS A JET MAX OVER THE AREA AND THE GFS 
SHOWS THE JET MAX JUST TO THE SOUTH OF THE AREA. BY TUESDAY MORNING 
THE GFS AND ECMWF SHOW ENOUGH LIFT TO GET PRECIPITATION OVER THE 
CWA. THEY BOTH SHOW ENOUGH 700MB OMEGA AND 500MB VORTICITY OVER THE 
CWA. LOOKING AT MODEL SOUNDINGS AND LOW LEVEL TEMPERATURES THE 
PRECIPITATION IS LIKELY TO START OUT AS A RAIN/SNOW MIX MONDAY 
NIGHT...PROGRESS ON TO JUST SNOW OVERNIGHT AND INTO TUESDAY 
MORNING...AND THEN BACK TO RAIN TUESDAY AFTERNOON. AS FOR WINDS 
THERE ARE NOT ANY INDICATIONS THAT THERE THIS WILL BE A HIGH WIND 
EVENT. THE 700MB WINDS ARE SHOWN TO BE ABOUT 35 KNOTS AND THE HEIGHT 
GRADIENT AT THAT LEVEL IS NOT IMPRESSIVE WITH THE LATEST MODEL RUNS. 

ANOTHER SOMEWHAT WEAKER UPPER/MID LEVEL TROUGH WILL MAKE ITS WAY 
THROUGH THE AREA THURSDAY. MODELS INDICATE ENOUGH LIFT AND MOISTURE 
IN THE NORTHERN PERMIAN BASIN AND SOUTHEASTERN NEW MEXICO FOR THERE 
TO CREATE SOME PRECIPITATION. THE COLD FRONT ASSOCIATED WITH THIS 
TROUGH WILL BRING TEMPERATURES BELOW NORMAL AGAIN...AND CAUSE ANY 
PRECIPITATION THAT FALLS TO BE IN THE FORM OF SNOW.

&&

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

&&

$$

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