FXUS64 KMAF 222317
AFDMAF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIDLAND/ODESSA TX
517 PM CST TUE DEC 22 2009

.DISCUSSION...
LATEST AVIATION DISCUSSION INCLUDED BELOW.

&&

.AVIATION...
VFR CONDITIONS WILL PREVAIL ACROSS SOUTHEAST NEW MEXICO AND WEST 
TEXAS THROUGH THE NEXT 24 HOURS.  MID AND HIGH CLOUDS WILL SCATTER 
OUT AT ALL TAF SITES THIS EVENING...BUT EXPECT LOWER VFR CEILINGS TO 
DEVELOP LATE TONIGHT AND WEDNESDAY MORNING AS A STRONG UPPER LEVEL 
STORM SYSTEM APPROACHES FROM THE WEST.  

WILL INCLUDE TEMPORARY GUSTY WINDS TO 35 TO 45KT BETWEEN 23/18Z AND 
24/00Z AT ALL TAF SITES AS AT LEAST SHOWERS DEVELOP OVER THE AREA 
ALONG WITH FAIRLY STRONG LOW TO MID LEVEL WINDS.  INSTABILITY 
APPEARS TO BE LACKING...ALTHOUGH THUNDER MAY BE ADDED TO PECOS... 
WINK...FORT STOCKTON AND MIDLAND ON LATER ISSUANCES IF FEATURES 
ASSOCIATED WITH THE UPPER SYSTEM ARE DEEMED TO BE COLLOCATED AS IT 
MOVES OVER THE REGION.  SINCE TEMPERATURES WILL COOL THROUGH THE 
ATMOSPHERIC COLUMN AS THE UPPER SYSTEM MOVES OVERHEAD...THERE IS 
ALSO AN OUTSIDE CHANCE SLEET MAY HAVE TO BE ADDED TO THESE TAF SITES 
IF THUNDER IS INCLUDED.  67

&&

.PREV DISCUSSION... /ISSUED 322 PM CST TUE DEC 22 2009/ 

DISCUSSION...
THE LATEST WATER VAPOR SATELLITE LOOP SHOWS A DEEP TROUGH OVER THE
WESTERN U.S. WITH A WEST TO EAST ORIENTED SUBTROPICAL JET LOCATED
ACROSS SOUTHERN AZ/NM AND NORTHERN MEXICO. THE 22/12Z RAOB DATA
SHOWS A SOLID AREA OF 100KT+ WINDS ACROSS THE DESERT SOUTHWEST AT
250MB...WITH THE LATEST GOES DERIVED WINDS SHOWING AROUND 140KT
FROM NORTHERN THE NORTHERN BAJA PENINSULA INTO NORTHERN CHIHUAHUA. 

THESE STRONG WINDS ALOFT WILL CONTINUE TO PUSH EAST INTO THE
REGION TONIGHT. WE EXPECT HIGH WINDS ACROSS THE GUADALUPE AND
DAVIS MOUNTAINS...AND AFTER LOOKING AT THE LATEST OBSERVATIONS
FROM THE BOWL RAWS (W 42G63 MPH) WE WILL START THE HIGH WIND
WARNING AT 21Z TODAY. AS THE LEFT FRONT QUADRANT OF THE UPPER JET
MOVES INTO THE REGION TONIGHT...SOME LIGHT PRECIPITATION IS
EXPECTED TO DEVELOP ACROSS THE GUADALUPE MOUNTAINS THIS EVENING.
PRECIPITATION SHOULD SPREAD EAST INTO THE VAN HORN REGION AND
SOUTHEAST NEW MEXICO PLAINS AFTER MIDNIGHT...WITH RAIN EXPECTED
BELOW 6000 FEET...AND A MIXTURE OF RAIN/SNOW ABOVE 6000 FEET.
ONLY LIGHT AMOUNTS OF PRECIPITATION ARE EXPECTED TONIGHT. THE
UPPER LEVEL JET CONTINUES TO AFFECT THE REGION ON WEDNESDAY AND
PRECIPITATION CHANCES WILL SPREAD EAST ACROSS MOST AREAS DURING
THE DAY. THE LATEST MODEL GUIDANCE HAS INCREASED QPF AMOUNTS AND
WE HAVE ALSO ADJUSTED QPF UP SLIGHTLY IN THE LATEST FORECAST. MOST
AREAS CAN EXPECT RAIN SHOWERS...BUT THE HIGHER ELEVATIONS OF THE
GUADALUPE AND DAVIS MOUNTAINS (GENERALLY ABOVE 6000 FEET) COULD
SEE UP TO AN INCH OF SNOW. THE MAIN UPPER TROUGH AXIS MOVES
THROUGH ON WEDNESDAY...HOWEVER MODELS SUGGEST A SECONDARY VORT MAX
ON THE BACK SIDE OF THE TROUGH COULD AID LIFT WEDNESDAY NIGHT INTO
THURSDAY. WE HAVE INCREASED POPS SLIGHTLY FOR WEDNESDAY NIGHT.
MOST OF THE PRECIPITATION ACROSS THE PLAINS SHOULD REMAIN IN
LIQUID FORM DURING THE EVENING. THE EXCEPTION BEING ACROSS THE
GUADALUPES WHERE SNOW IS EXPECTED...ALONG WITH A MIXTURE OF
RAIN/SNOW ACROSS NORTHERN LEA COUNTY. DURING THE LATE EVENING AND
OVERNIGHT HOURS...THE NORTHERN STREAM COLD FRONT WILL MOVE THROUGH
AND A TRANSITION TO MORE OF A RAIN/SNOW MIX WILL SPREAD ACROSS THE
PERMIAN BASIN. GIVEN EXPECTED QPF AMOUNTS...ANY SNOWFALL AMOUNTS
SHOULD REMAIN VERY LIGHT. MUCH COOLER TEMPERATURES ARE EXPECTED ON
THURSDAY AND WITH THE LATEST GUIDANCE SHOWING SOME LIGHT
PRECIPITATION ACROSS SOUTHEAST NEW MEXICO...WE HAVE ADDED A SLIGHT
CHANCE FOR SNOW SHOWERS FOR NORTHERN LEA COUNTY. 

A DEEP...UPPER LOW IS EXPECTED TO REMAIN ACROSS THE CENTRAL U.S.
THROUGH MOST OF THE UPCOMING WEEKEND. WITH THIS PATTERN...
PERSISTENT SURFACE RIDGING SHOULD SET UP ACROSS THE REGION. THIS
WILL BRING BELOW NORMAL TEMPERATURES TO THE AREA THROUGH THE BULK
OF THE FORECAST. THE LATEST MEDIUM RANGE MODELS ARE SHOWING AN
UPPER LEVEL LOW APPROACHING EARLY NEXT WEEK. ALTHOUGH THERE IS
GOOD AGREEMENT NOW...SUBSEQUENT MODEL RUNS WILL LIKELY DIFFER AND
WILL OPT TO HOLD OFF ON MENTIONING ANY PRECIPITATION NOW.

&&

.MAF WATCHES/WARNINGS/ADVISORIES...
NM...HIGH WIND WARNING UNTIL 5 PM MST WEDNESDAY FOR THE FOLLOWING 
     ZONES... GUADALUPE MOUNTAINS OF EDDY COUNTY.

TX...HIGH WIND WARNING UNTIL 6 PM CST /5 PM MST/ WEDNESDAY FOR THE 
     FOLLOWING ZONES... DAVIS/APACHE MOUNTAINS AREA...GUADALUPE 
     MOUNTAINS.

&&

$$

06/78