000
FXUS64 KLUB 300548
AFDLUB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LUBBOCK TX
1148 PM CST THU JAN 29 2015

.AVIATION...
VFR CONDITIONS LOOK TO CONTINUE THROUGH MUCH OF FRIDAY AFTERNOON
WITH LIGHT NORTHEAST WINDS VEERING SOUTHEASTERLY THROUGH THE DAY.
MID TO HIGH CLOUDS WILL WORK DOWN THROUGH THE PERIOD...WITH KLBB
AND KPVW LIKELY SEEING MVFR CEILINGS BY 00-01Z SATURDAY.
CONFIDENCE NOT HIGH ENOUGH IN KCDS SEEING SUB-VFR CEILINGS PRIOR
TO 06Z SATURDAY TO INSERT MENTION AT THIS TIME. -RA WILL ALSO
BEGIN TO IMPACT ALL SITES AFTER 00Z AHEAD OF AN UPPER LEVEL
DISTURBANCE OFF TO OUR SOUTHWEST. ANY FROZEN PRECIPITATION LOOKS
TO REMAIN WEST OF ALL TAF SITES THROUGH THE PERIOD.

&&

PREV DISCUSSION... /ISSUED 254 PM CST THU JAN 29 2015/

SHORT TERM...
A MOISTURE LADEN UPPER LOW OFF BAJA LATE THIS AFTERNOON WILL MOVE
SLOWLY INTO THE MOJAVE DESERT FRIDAY AFTERNOON. AN UPPER LEVEL HIGH
PRESSURE RIDGE AXIS PASSING OVERHEAD TONIGHT WILL EDGE EAST FRIDAY
WITH DEEPENING MOISTURE AND INCREASING UPWARDS FORCING WORKING
THROUGH WESTERN INTO CENTRAL ZONES DURING THE DAY. A NOTABLE DRY
LAYER BELOW 750 MILLIBARS WILL BE IN PLACE WITH A TOP-DOWN
MOISTENING PROCESS EXPECTED TO LEAD TO PRECIPITATION SPREADING WEST
TO EAST ON FRIDAY...THOUGH EXISTENCE OF THIS LAYER ADDS CONSIDERABLE
UNCERTAINTY TO TIMING OF PRECIPITATION ONSET AND PRECIPITATION
AMOUNTS AS WE HAVE SEEN MANY TIMES PREVIOUSLY THIS WINTER. SHOWERS
ALREADY APPROACHING THE RIO GRANDE VALLEY IN FAR WEST TEXAS WILL
MOVE CLOSER OVERNIGHT AND NOT IMPROBABLE THAT LIGHT SHOWERS MAY
SPREAD INTO WESTERN AREAS. A COOL SURFACE HIGH PRESSURE RIDGE WILL
JUT SOUTHWARD THROUGH THE AREA WITH CENTER TO OUR NORTHEAST. LOW
LEVEL FLOW EXPECTED TO GRADUALLY VEER TO THE SOUTHEAST. NOT A VERY
COLD SURFACE RIDGE BY ANY MEANS FOR LATE JANUARY...AND THERMAL
PROFILES FOR CENTRAL AND EASTERN AREAS THROUGH FRIDAY CONTINUE TO
FAVOR LIQUID PRECIPITATION. DYNAMIC COOLING IS EXPECTED TO DRAW THE
THERMAL PROFILE COLD ENOUGH TO FAVOR MAINLY SNOW FRIDAY FOR WESTERN
BORDER...WITH A PHASE TRANSITION LIKELY REMAINING ACROSS WESTERN
COUNTIES THOUGH A BRIEF SLEET OR SNOW SHOWER CENTRAL ZONES ALSO NOT
ENTIRELY OUT OF THE QUESTION. STEADIER PRECIPITATION SHOULD
GRADUALLY TAKE OVER WESTERN AREAS ON FRIDAY AND MAY LEAD TO MOSTLY
UNDER 1 INCH ACCUMULATIONS OF WET SNOW NORTHWEST BORDER WITH OUTSIDE
RISK OF MAYBE ANOTHER INCH. BETTER CHANCES WILL EXPAND THROUGH THE
AREA FRIDAY NIGHT. FEW SIGNIFICANT CHANGES FROM THE PREVIOUS
FORECAST FOR THIS GO-AROUND. RMCQUEEN

LONG TERM...
ONLY MINOR CHANGES WERE MADE TO THE CURRENT FORECAST OF THIS
WEEKENDS PRECIPITATION SYSTEM. A LARGE PLUME OF SUBTROPICAL MOISTURE
WAS OBSERVED ON WATER VAPOR IMAGERY SPREAD OVER THE SOUTHWESTERN US
INTO WEST TEXAS. ALTHOUGH MID AND UPPER LEVELS WILL BE MOIST THROUGH
TOMORROW...LOW LEVELS WILL BE SLOW TO MOISTEN UP OFF THE CAPROCK
WITH SHORT WAVE RIDGING MOVING OVER THE AREA. DEEP MOIST ISENTROPIC
UPGLIDE WILL MANIFEST ITSELF FRIDAY NIGHT INTO SATURDAY MORNING AND
EXPECT THE BULK OF PRECIPITATION TO FALL DURING THIS TIME PERIOD.
DOWNGLIDE WILL BEGIN TO WORK ITS WAY IN FROM THE NORTH AT THE LOWEST
LEVELS AS EARLY AS SATURDAY AFTERNOON. PRECIPITATION WILL BE QUICK
TO END SATURDAY EVENING AS DRY NORTHWEST FLOW AND LARGE SCALE
SUBSIDENCE AS A NORTHERN STREAM TROUGH AXIS MOVES INTO THE REGION.

CONFIDENCE IS INCREASING IN MOSTLY RAIN FOR AREAS OFF THE CAPROCK
AND THE SOUTH PLAINS. LATEST MODEL RUNS HAVE TRENDED WARMER UNDER
VERY STRONG LOW LEVEL WARM AIR ADVECTION FRIDAY NIGHT. THE GREATEST
SNOW THREAT WILL BE ACROSS THE SOUTHWESTERN TEXAS PANHANDLE WHERE
WEAKER WAA WILL BE SEEN. SNOW TOTALS UP TO FOUR INCHES WOULD BE
LIKELY AND MOSTLY ON GRASSY AREAS WITH SURFACE TEMPERATURES AROUND
-2 TO 0C. A STRONG COLD FRONT WILL PLOW THROUGH ON SUNDAY DIPPING
TEMPERATURES BELOW SEASONAL AVERAGES BUT WILL BE SHORT LIVED. LEE
TROUGHING WILL RETURN NEXT WEEK UNDER DRY NORTHWEST FLOW. THERE MAY
BE ANOTHER INTERRUPTION TO THE WARMUP ON WEDNESDAY WITH ANOTHER COLD
FRONT AND AGAIN LATE NEXT WEEK.

&&

.PRELIMINARY POINT TEMPS/POPS...
FRIONA        50  31  35  29 /   0  20  60  80
TULIA         53  32  40  33 /   0  10  50  80
PLAINVIEW     53  34  40  33 /   0  10  50  90
LEVELLAND     56  33  38  33 /   0  20  60  90
LUBBOCK       56  34  40  34 /   0  10  50  90
DENVER CITY   56  35  39  34 /   0  30  60  90
BROWNFIELD    57  34  40  35 /   0  20  50  90
CHILDRESS     59  34  48  38 /   0   0  20  80
SPUR          58  34  45  36 /   0  10  20  80
ASPERMONT     60  35  48  39 /   0   0  20  80

&&

.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

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