FXUS64 KLUB 260957
AFDLUB
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LUBBOCK TX
357 AM CST SAT DEC 26 2009
.SHORT TERM...
REGIONAL SATELLITE IMAGERY REVEALED A CONFLUENT UPPER FLOW ACROSS
MUCH OF THE REGION THIS MORNING RESULTING IN WIDESPREAD CLEAR
SKIES. NEAREST PRECIPITATION WAS FOUND IN ERN COLORADO WEST OF A
FILLING UPPER LOW...AND IT/S THIS FEATURE THAT WILL DRIVE A
SHEARED OUT TROF AND ASSOCIATED DIFFUSE SURFACE BOUNDARY THROUGH
THE CWA TODAY. NEGLIGIBLE CHANGE IN LOW-LEVEL THICKNESSES AND MORE
IMPORTANTLY A DIMINISHED SNOW COVER SHOULD PUSH MAX TEMPS A FEW
DEGREES OVER YESTERDAY/S READINGS...BUT STILL FALLING WELL SHORT
OF CLIMO. W-NWLY UPPER FLOW THEN RELAXES TONIGHT AS WEAK HEIGHT
RISES FILTER IN AHEAD OF LOW-AMPLITUDE RIDGING. LASTLY...LOW-
LEVELS TONIGHT WILL AGAIN BE HOST TO LIGHT WINDS WITH BORDERLINE
SATURATION...HOWEVER THE ONLY REDUCED VIS THIS MORNING THUS FAR
HAS BEEN OBSERVED AT KPVW...AND THIS PROVED VERY BRIEF. WILL
THEREFORE OMIT PATCHY FZFG MENTION TONIGHT AS SIGNALS ARE NO MORE
COMPELLING THAN THE RECENT OBSERVED TRENDS.
&&
.LONG TERM...
TEMPERATURES APPEAR TO STAY ANYWHERE FROM 5 TO 10 DEGREES BELOW
NORMAL FOR THIS TIME OF YEAR THROUGH THE END OF THE FORECAST.
THROUGH SUNDAY...NORTHWESTERLY FLOW REMAINS IN PLACE WHICH HELPS
TO KEEP THE COLD AIR OVER THE REGION WITH GENERALLY WEAK NORTH TO
NORTHWESTERLY SURFACE FLOW THROUGH THE WEEKEND. BY LATE SUNDAY...
FLOW ALOFT DOES TRANSITION OVER TO MORE OF A ZONAL COMPONENT AS
THE STORM SYSTEM THAT BROUGHT SNOW TO THE REGION FINALLY STARTS TO
SLIDE EAST AWAY FROM THE GREAT LAKES AND A NEW STORM SYSTEM STARTS
TO DEEPEN OFF THE CALIFORNIA COAST.
EVEN THOUGH SURFACE WINDS START TO VEER AHEAD OF THE APPROACHING
TROF...COLD AIR WILL CONTINUE TO BE RECYCLED ACROSS THE REGION AS
THE SURFACE HIGH REMAINS PARKED OVER OKLAHOMA OR NORTH TEXAS. ALSO
HELPING TO KEEP TEMPERATURES DOWN WILL BE INCREASING CLOUD COVER
AS THE FLOW ALOFT BECOMES SOUTHWESTERLY WHICH POTENTIALLY SHOULD
PULL IN A CIRRUS SHIELD. AT THE SAME TIME...SOME WEAK RETURN FLOW
TRIES TO DEVELOP ABOVE THE SURFACE. BOTH THE GFS AND CMC SHOW WEAK
PRECIP AMOUNTS STARTING OVERNIGHT MONDAY THROUGH THE DAY TUESDAY
BEFORE SHIFTING EAST TUESDAY NIGHT. CONTINUED POPS THROUGH THIS
PERIOD AND IT STILL APPEARS THAT PRECIP WILL FALL IN THE FORM OF
SNOW. TEMPERATURE PROFILES AS SHOWN IN AREA SOUNDINGS SHOW THE
COLUMN REMAINING BELOW FREEZING UNTIL LATE IN THE DAY BUT WOULD
NOT BE SURPRISED IF COMBINATION OF PRECIPITATION...CLOUD COVER...
AND WET BULB COOLING FROM THE PRECIP HOLDS TEMPERATURES AT OR A
FEW DEGREES ABOVE FREEZING. WILL HAVE TO EVALUATE AS WE GET CLOSER
TO TUESDAY.
HEADING INTO THE END OF THE FORECAST...ECMWF CONTINUES TO DEVELOP
A SECOND WAVE THAT PUSHES OVER THE AREA WEDNESDAY AND THE GFS HAS
PICKED UP ON THIS FEATURE AS WELL BUT IS ABOUT 12 TO 24 HOURS
BEHIND THE ECMWF. CMC IS ALSO TRYING TO LATCH ONTO THIS FEATURE AS
WELL. THIS IS STILL CAUSING DISCREPANCIES FOR TEMPERATURES AS THE
ECMWF MAINTAINS NORTHERLY SFC FLOW FROM WED THROUGH THE END OF THE
FCST WHILE THE GFS HAS THE FRONT PUSHING IN FOR THUR AND FRI
BEFORE TRYING TO SWING WINDS BACK AROUND TO THE SOUTH BY NEXT
WEEKEND. WAY TOO EARLY TO TRY AND FIGURE OUT IF THIS SECOND WAVE
WILL PROVIDE THE AREA WITH ANOTHER SHOT OF PRECIP OR IF MOISTURE
WILL BE LACKING...BUT DID OPT ONCE AGAIN TO RUN WITH THE COOLER
ENSEMBLE MOS GUIDANCE VALUES FOR TEMPERATURES AND HELD POPS AROUND
10 PERCENT THROUGH THE END OF THE FCST.
JORDAN
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 33 9 38 15 38 / 0 0 0 0 0
TULIA 36 13 38 14 41 / 0 0 0 0 0
PLAINVIEW 36 12 39 11 42 / 0 0 0 0 0
LEVELLAND 39 15 39 12 41 / 0 0 0 0 0
LUBBOCK 40 13 39 12 42 / 0 0 0 0 0
DENVER CITY 42 19 42 20 42 / 0 0 0 0 0
BROWNFIELD 42 18 41 16 42 / 0 0 0 0 0
CHILDRESS 43 22 40 23 43 / 0 0 0 0 0
SPUR 41 18 42 20 45 / 0 0 0 0 0
ASPERMONT 42 20 45 23 47 / 0 0 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
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