HAMweather.com Area Forecast Discussion for County Warning Area MAF

Thu, 16 Feb 2012 09:05:16 GMT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIDLAND/ODESSA TX
1053 PM CST WED FEB 15 2012

.DISCUSSION...

SEE 06Z AVIATION DISCUSSION BELOW.

.AVIATION...

LATEST SFC OBS/ANALYSIS SHOW COLD FRONT MAKING PROGRESS THRU THE
FA...AHEAD OF AN UPPER TROUGH OVER SRN NV AS PER WV IMAGERY.
EXPECT SFC WINDS TO KEEP VEERING TO THE EAST THURSDAY...AND
INCREASE IN RESPONSE TO A SFC TROUGH PROGGED TO STRENGTHEN IN OLD
MEXICO AS AHEAD OF THE UPPER TROUGH...PROGGED TO DIG SOUTH INTO
THE GULF OF CALIFORNIA BY 06Z FRIDAY. GIVEN THE EXPECTED AMT OF
HIGH CLOUD THURSDAY...AND EASTERLY FLOW...HAVE LEFT GUSTS OUT OF
THE TAFS ATTM. FOR THURSDAY NIGHT...BOTH THE NAM AND GFS USHER IN
LOW CLOUDS BUT...AS USUAL...DIFFER IN CLOUD HEIGHTS. FORECAST NAM
SOUNDINGS BRING IN CIGS AFTER 00Z AS LOW AS IFR AT THE NRN
TERMINALS...TO MVFR IN THE SOUTH...WHEREAS THE GFS STAYS VFR.
SINCE THIS IS FCST TO OCCUR AT THE END OF THE FCST PD...WE/LL
STRIKE A COMPROMISE...KEEPING ALL TERMINALS AT MINIMAL VFR. 

.PREV DISCUSSION... /ISSUED 503 PM CST WED FEB 15 2012/ 

DISCUSSION...

SEE AVIATION DISCUSSION BELOW.

AVIATION...

VFR CONDITIONS ARE EXPECTED NEXT 24 HRS.  LATEST SFC ANALYSIS
SHOWS DECENT PRESSURE RISES UP IN THE PANHANDLE AS A COLD FRONT
MOVES SOUTH INTO THE AREA.  EXPECT GUSTY WEST WINDS TO DECOUPLE
WITH SUNDOWN...AND THEN VEER TO THE NORTH OVERNIGHT W/FROPA...AND
THEN TO THE EAST THURSDAY AS THE SFC RIDGE DRIFTS SE.  ONLY
MID/HIGH CLOUD EXPECTED.

PREV DISCUSSION... /ISSUED 303 PM CST WED FEB 15 2012/ 

DISCUSSION...
ON WATER VAPOR IMAGERY THERE IS AN UPPER LEVEL TROUGH OVER THE TEXAS 
PANHANDLE AND AN UPPER LEVEL LOW OVER SOUTHERN NEVADA. THE HEIGHT 
GRADIENT OVER THE AREA IN THE MID LEVEL IS PRETTY TIGHT WERE PRETTY 
TIGHT THIS MORNING JUST WEST OF THE GUADALUPE MOUNTAINS. WINDS 
ACROSS THE GUADALUPE MOUNTAINS WERE AROUND 50 MPH FOR MOST OF THE 
DAY. AS THE AFTERNOON PROGRESSES...THE UPPER LEVEL TROUGH MOVES 
FURTHER AWAY FROM THE AREA AND THE GRADIENT LOOSENS THE WINDS WILL 
DIE DOWN. THEREFORE...THE HIGH WIND WARNING HAS BEEN ALLOWED TO 
EXPIRE. A WEAK COLD FRONT WILL MAKE ITS WAY INTO THE AREA 
TONIGHT...WHICH WILL BRING LOW TEMPERATURES FOR THURSDAY MORNING 
DOWN ABOUT 10 DEGREES FROM WHAT THEY WERE THIS MORNING. LOW TEMPS 
WILL RANGE FROM THE UPPER 20S TO THE UPPER 30S ACROSS THE AREA.

THE NEXT FEATURE THAT WILL IMPACT THE WEATHER OF THE AREA WILL BE 
THE UPPER LEVEL LOW THAT IS CURRENTLY OVER SOUTHERN NEVADA. THERE IS 
FAIRLY DECENT AGREEMENT FOR THE TRACK THAT THIS SYSTEM WILL 
TAKE...BUT THAT IS WHERE THE AGREEMENT ENDS. THIS FEATURE WILL DIG 
SOUTH EAST AND ACROSS THE NORTHERN PORTIONS OF MEXICO. THE LAST 2 
RUNS OF THE GFS HAVE MIGRATED ACROSS NORTHERN MEXICO AND FILLED THE 
CUT OFF LOW INTO A TROUGH...AND MOVED IT EAST THE FASTEST. THE 
LATEST NAM HAS KEPT IT A CUT OFF LOW BUT MOVED THE TRACK SLIGHTLY 
SOUTH FROM THE TRACK THAT THE PREVIOUS MODEL RUN SHOWED...WHICH 
LOOKS MORE LIKE THE TRACK THE GFS SHOWS. THE TRACK THAT THE ECMWF 
SHOW IS A SLIGHTLY FURTHER NORTH...DIRECTLY THROUGH THE CWA. THE NAM 
SHOWS A STRONGEST IMPACT ON THE AREA. IT HAS THE HIGHEST QPF VALUES 
AND MOVES IT THROUGH THE AREA THE SLOWEST INCREASING THE DURATION OF 
IMPACTS. SINCE THE NAM HAS HANDLED THE LAST FEW UPPER LEVEL STORM 
SYSTEMS THE BEST HAVE TRENDED THE FORECAST IN THAT DIRECTION. AS 
WITH THE LAST SEVERAL SIGNIFICANT UPPER LEVEL LOWS THAT PASSED 
THROUGH THE AREA WHAT FORM OF PRECIPITATION WILL BE THE BIGGEST 
CHALLENGE. LOOKING AT MODEL SOUNDINGS AND THE WARM 850MB TEMPS THE 
PRECIP WILL START OUT AS RAIN. THE WESTERN PORTIONS OF THE CWA MAY 
SEE PRECIPITATION AS EARLY AS THURSDAY NIGHT/FRIDAY MORNING. THERE 
IS NOT MUCH IN THE WAY OF INSTABILITY WITH THIS SYSTEM...SO THUNDER 
WAS LEFT OUT AT THIS TIME. AS THE CORE OF THE SYSTEM GETS CLOSER TO 
THE AREA IT WILL BRING COLDER AIR IN THE UPPER LEVELS WITH IT...SO A 
SNOW AND RAIN MIX HAS BEEN FORECASTED FRIDAY NIGHT. HAVE BUMPED UP 
POPS SLIGHTLY FRIDAY NIGHT AS WELL. BY SATURDAY AFTERNOON THE UPPER 
LEVEL SYSTEM WILL HAVE MIGRATED INTO CENTRAL TEXAS.

FIRE WEATHER...
A RANGELAND FIRE DANGER STATEMENT FOR LOCATIONS ALONG AND EAST OF A 
CARLSBAD TO ALPINE LINE WILL REMAIN INTACT THROUGH THIS AFTERNOON. 
ELEVATED FIRE WEATHER CONDITIONS CAN BE EXPECTED AS MINIMUM RH/S 
FALL TO NEAR 15% AND WESTERLY WINDS REMAIN GUSTY. WINDS WILL BE ON 
THE DECREASE BY LATE AFTERNOON AS RH/S FALL TO NEAR 15%. WINDS WILL 
CONTINUE TO DECREASE THIS EVENING AS RH/S SLOWLY CLIMB. 

A COLD FRONT WILL THEN MOVE SOUTH THROUGH THE PLAINS AFTER 
MIDNIGHT... BRINGING A NORTHEASTERLY WIND SHIFT AND INCREASING RH/S 
TO AREAS GENERALLY EAST OF THE PECOS RIVER. ON THURSDAY...THE COLD 
FRONT WILL CONTINUE TO PUSH INTO THE HIGHER TERRAIN OF THE TRANS 
PECOS REGION...RESULTING IN EASTERLY WINDS AND COOLER TEMPERATURES.

AN UPPER LEVEL STORM SYSTEM WILL APPROACH FROM THE WEST THURSDAY 
NIGHT...BRINGING BELOW NORMAL TEMPERATURES AND A CHANCE OF 
PRECIPITATION TO MOST AREAS THROUGH SATURDAY MORNING.

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