FXUS64 KLUB 262323
AFDLUB
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LUBBOCK TX
523 PM CST SAT DEC 26 2009
.AVIATION...
THE POSSIBILITY OF REDUCED VSBYS IN FOG WILL BE PRESENT THIS EVE
OVER THE REMAINING SNOWPACK PRIMARILY AT KLBB. RUC MODEL INDICATES
SURFACE LAYER NEARING SATURATION BY AROUND 03Z WITH LIGHT WINDS. DEWPOINT
DEPRESSIONS THEN WIDEN AFTER 06Z AS SURFACE WINDS VEER NW AND
INCREASE TO NR 10KT. PATCHY BR THREAT SHIFTS SOUTH OF KLBB
TERMINAL WITH VFR CONDITIONS REMAINDER OF THE NIGHT. WILL MAINTAIN
FOG MENTION AT KLBB BUT REDUCE THE LENGTH OF TIME IN TAF.
&&
.PREV DISCUSSION... /ISSUED 308 PM CST SAT DEC 26 2009/
SHORT TERM...
GENERALLY CLEAR SKIES AND LIGHT WINDS WILL BE THE TREND FOR THE NEXT
24 HOURS. TEMPERATURES AND MOISTURE LEVELS WILL CONTINUE TO BE THE
MOST SIGNIFICANT FCST UNCERTAINTIES AS SNOW PACK IS KEEPING TEMPS
DOWN FOR HIGHS. WITH LIGHT WINDS...EXPECT VERY COLD NIGHT TIME LOWS
TO CONTINUE AT LEAST ANOTHER NIGHT. ARGUMENT FOR FREEZING FOG LOOKS
TO BE A BIT BETTER TONIGHT THAN YESTERDAY...HOWEVER...GUIDANCE
CONTINUES TO OVERDO THE MOISTENING OF THE SFC LAYER DUE TO
EVAP/SUBLIMATION. WILL THEREFORE KEEP MENTION OF FZFG IN THE
GRIDS. INTO TOMORROW...A FEW HIGH CLOUDS MAY WORK THEIR WAY IN FROM
THE SOUTHEAST...BUT TEMPS MAY NOT GET TO MUCH ABOVE TODAY/S VALUES
IN AREAS WHERE THE SNOW PACK REMAINS. 26
LONG TERM...
FOCUS IN THE EXTENDED CONTINUES TO BE ON SNOW CHANCES FOR TUE.
SFC RIDGE SETTLES IN ACROSS THE AREA ON MONDAY WHICH SHOULD KEEP
TEMPS FROM RISING MUCH IF AT ALL FROM SUNDAY/S HIGHS. HIGH CLOUDS
SHOULD INCREASE LATE IN THE DAY IN ADVANCE OF STORM SYSTEM TO OUR
SW.
GUIDANCE IS IN BROAD AGREEMENT WITH THE TRACK OF THE INCOMING
WAVE. THE GFS REMAINS THE FASTEST WITH THE EURO AND WRF/NAM LAGGING
BEHIND...SO FOR THIS FCST HAVE TRIED TO ROUGHLY SPLIT THE
DIFFERENCE. LARGE SCALE ASCENT WILL BEGIN TO INCREASE ACROSS THE
AREA MONDAY NIGHT AS H5 DIVERGENCE AND LEFT-EXIT REGION OF ULJ
APPROACH FROM THE SW. GIVEN THE TIMING DIFFERENCES...WILL HOLD ON
TO CURRENT POP GRIDS SHOWING PRECIP CHANCES BEGINNING AFTER MIDN
ACROSS THE WEST...SPREADING EAST ACROSS THE FA DURING THE DAY AND
THEN CONFINED TO THE EASTERN ROLLING PLAINS AFTER 0Z WED. DID
RAISE POPS INTO CHC CATEGORY ACROSS ALL BUT THE NRN TIER...GIVEN
THE FCST TRACK OF THE SYSTEM. GUIDANCE STILL DEPICTS THAT THE TEMP
PROFILE WILL REMAIN BELOW FREEZING ABOVE THE SFC /AND VERY NEAR
FREEZING AT THE SFC/...SUCH THAT THERE IS A HIGH LIKELIHOOD THAT
P-TYPE WILL BE ALL SNOW. HOWEVER...IN THE LOWER ELEVATIONS OF THE
ROLLING PLAINS THE PROFILE IS CLOSE ENOUGH TO MENTION A RAIN/SNOW
MIX FOR NOW. AS FOR PRECIP/SNOW AMOUNT...STILL UNCERTAIN HOW MUCH
MOISTURE WILL BE FED INTO THIS SYSTEM. SNOWFALL AMOUNTS IN THE
1-2 INCH RANGE WOULD APPEAR TO BE QUITE PLAUSIBLE FOR THIS
STORM...BUT WILL WATCH FOR ANY INDICATION OF HEAVIER AMOUNTS
ACROSS A SMALLER AREA AS WE GET CLOSER.
GUIDANCE ALSO NOW IN GOOD AGREEMENT IN BRINGING A TRAILING
SHORTWAVE ACROSS THE AREA WED. SOME CONCERN THAT WE COULD SEE SOME
LIGHT SNOW SHOWERS REDEVELOP AS THIS TROUGH PASSES BY BUT MOISTURE
SHOULD BE SPARSE SO FOR NOW HAVE KEPT POPS UNDER MENTION BUT
RAISED SKY COVER AND KEPT FCST TEMPS UNDER GUIDANCE.
COOL...DRY NW FLOW ALOFT THEN BECOMES ESTABLISHED ACROSS NW TX
THROUGH THE END OF THE WEEK. GFS BRINGS ANOTHER SHTWV THROUGH THE
AREA THU GENERATING SOME LIGHT QPF BUT ECMWF IS WEAKER/DRIER. AT
SOME POINT...PERHAPS FRIDAY...ANOTHER SURGE OF COLD AIR WILL MOVE
INTO THE SOUTH PLAINS AND PERHAPS SET UP THE NEXT CHANCE FOR
LIGHT PRECIP IF ANY SHORTWAVE ENERGY TRAVERSES THE AREA FRI/SAT. WILL
KEEP THE REST OF THE FCST INTO NEXT WEEKEND DRY FOR NOW BUT
MAINTAIN THE BELOW NORM TEMPS WITH LITTLE MODERATION EXPECTED.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 8 39 14 39 20 / 0 0 0 0 20
TULIA 12 40 14 40 23 / 0 0 0 0 10
PLAINVIEW 11 39 13 40 23 / 0 0 0 0 10
LEVELLAND 14 37 14 40 24 / 0 0 0 0 20
LUBBOCK 12 38 14 40 25 / 0 0 0 0 10
DENVER CITY 18 47 19 42 25 / 0 0 0 0 20
BROWNFIELD 17 38 17 41 25 / 0 0 0 0 20
CHILDRESS 21 42 23 43 28 / 0 0 0 0 10
SPUR 17 43 21 43 26 / 0 0 0 0 10
ASPERMONT 19 44 23 44 27 / 0 0 0 0 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
24/06/99
