Area Forecast Discussion
Issued by NWS

Skip options and go directly to product.
Home | Oldest Version | Previous Version | Current Version | All | Text Only | Save Text | Print | Product List | Glossary Off

Skip product version selection by date and time.   

018
FXUS64 KLUB 181720
AFDLUB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LUBBOCK TX
1120 AM CST THU DEC 18 2014

.AVIATION...
IFR OR LOWER END OF MVFR CATEGORY BEHIND A WEAK COLD FRONT WILL
RETREAT SLOWLY NEWD...ENOUGH TO CLEAR KPVW THIS AFTN BUT NOT AT
KCDS. A SURGE OF NORTHEAST TO EAST WINDS AHEAD OF AN UPPER LEVEL
DISTURBANCE WILL DRAW THIS STRATUS BACK TO THE WEST THIS WEEK AND
IFR CIGS LIKELY AT KPVW AND KLBB. 12Z MODEL SUITE CONTINUES TO
ADVERTISE SCATTERED...GENERALLY LIGHT RAIN SHOWERS SPREADING FROM
WEST TO EAST LATE TONIGHT THROUGH FRIDAY MORNING. BEST CHANCES
SOUTH OF A KPVW TO KCDS LINE. WILL KEEP MENTION OUT OF THOSE
TERMINALS ATTM BUT INSERT A MENTION OF -SHRA AT KLBB.

&&

.PREV DISCUSSION... /ISSUED 530 AM CST THU DEC 18 2014/

AVIATION...
VFR CONDITIONS IN PLACE AT KLBB AND KPVW WHILE LIFR CONDITIONS ARE
HANGING ON AT KCDS. EXPECT TO SEE KCDS IMPROVE BACK INTO MVFR
RANGE AROUND SUNRISE AND REMAIN IN THE MVFR TO VFR RANGE THROUGH
THE DAY. KLBB SHOULD REMAIN VFR THROUGH MUCH OF THE DAY. KPVW IS
PROBLEMATIC BECAUSE OF A WEAK COLD FRONT PUSHING SOUTH TOWARDS
THIS TERMINAL. COMPUTER FORECASTS HAVE LIFR TO VLIFR CONDITIONS
POSSIBLY IMPACTING KPVW THIS MORNING AND AWOS/ASOS SITES BEHIND
THE FRONT ARE ALL LIFR TO VLIFR. GOOD NEWS IS THAT IT APPEARS THAT
LIFR SHOULD STAY NORTH OF KLBB TERMINAL AND HAVE WRITTEN TAFS
ACCORDINGLY. EXPECT CONDITIONS TO GO MVFR AGAIN TONIGHT AND THEN
IFR TO LIFR EARLY FRIDAY MORNING AS A STORM SYSTEM APPROACHES THE
REGION. CONFIDENCE IS HIGH THAT THERE WILL BE PRECIPITATION WITH
THIS SYSTEM BUT LOW IN THE TIMING. OPTED TO LEAVE MENTION OF
PRECIP OUT OF THE TAFS FOR NOW UNTIL TIMING CAN BE FIRMED UP
THROUGH THE DAY...BUT MOST FAVORED TIME WILL BE 06Z - 12Z FRIDAY
MORNING AT KLBB AND KPVW...12Z-18Z KCDS.

JORDAN

PREV DISCUSSION... /ISSUED 400 AM CST THU DEC 18 2014/

SHORT TERM...
LOW CLOUDS AND FOG BLANKETED THE ROLLING PLAINS THIS MORNING WHILE
IT HAS BEEN FLIRTING WITH THE EASTERN PORTIONS OF THE CAPROCK
THROUGH THE EARLY MORNING HOURS.  SURFACE WIND ACROSS THE CAPROCK
HAS STARTED TO VEER TO THE WEST WHICH IS HELPING TO PULL IN SOME
DRIER AIR AS WELL AS KEEP MIXING UP TO PREVENT FORMATION OF FOG.
LIGHT AND VARIABLE TO WEAK SOUTHEASTERLY WIND ACROSS THE ROLLING
PLAINS IS HOLDING MOISTURE IN PLACE AND WILL LIKELY DO SO THROUGH
MUCH OF THE DAY.  ALOFT...THE FORECAST AREA REMAINS BETWEEN TWO
STORM SYSTEMS THAT ARE PROGRESSIVELY MOVING EAST ACROSS THE UNITED
STATES.  NEXT ONE TO IMPACT US WAS LOCATED OVER SOUTHERN CALIFORNIA
AND WILL MAKE FAST PROGRESS TO THE EAST THROUGH THE DAY.

WILL SEE A SIMILAR TEMPERATURE GRADIENT ACROSS THE FORECAST AREA
TODAY THAT WE SAW YESTERDAY WITH COOL UPPER 40S TO NEAR 50 ACROSS
THE ROLLING PLAINS TO NEAR 60 ACROSS THE SOUTHWESTERN SOUTH PLAINS.
AS THE STORM SYSTEM OVER SOUTHERN CALIFORNIA APPROACHES THE REGION
LATE TONIGHT INTO TOMORROW...SURFACE WIND WILL START TO SWING BACK
TO THE EAST ACROSS THE REGION WHICH WILL BRING MOIST UPSLOPE AND
RETURN FLOW.  MODELS INDICATE THAT WE SHOULD SEE ANOTHER ROUND OF
LOW CLOUDS AND FOG SPREAD FROM EAST TO WEST ACROSS THE AREA AROUND
MIDNIGHT AND PERSISTING THROUGH MUCH OF OVERNIGHT HOURS.  AT THE
SAME TIME...SYNOPTIC-SCALE LIFT WILL START TO INCREASE WITH THE
APPROACH OF THE STORM SYSTEM.  BEST TIME FRAME FOR PRECIPITATION
LOOKS TO BE IN THE 06Z TO 12Z TIME FRAME FRIDAY MORNING STARTING
ACROSS THE SOUTHWESTERN SOUTH PLAINS AND SPREADING ACROSS THE
SOUTHERN HALF OF THE FORECAST AREA. MODELS ARE PRETTY AGGRESSIVE
ON PRECIPITATION AMOUNTS WITH THE NAM THE BIG WINNER WITH SOME
HALF-INCH TOTALS WHILE THE OTHER MODELS ARE MUCH LOWER IN LIQUID
AMOUNTS.

BIGGEST QUESTION...OTHER THAN WHERE THE GREATEST AMOUNTS OF
PRECIPITATION WILL BE...IS WHETHER WE WILL SEE A MIX OF RAIN AND
SNOW ACROSS THE NORTHWESTERN QUARTER TO THIRD OF THE AREA.
TEMPERATURES WILL BE CLOSE ENOUGH TO FREEZING AT THE SURFACE THAT
LOCATIONS NORTH AND WEST OF A LEVELLAND TO SILVERTON LINE MAY SEE A
MIX OF WINTRY PRECIPITATION IN THE MORNING. ANY ACCUMULATIONS
WILL BE VERY LIGHT AND WILL PROBABLY BE NOTICEABLE ONLY ON GRASSY
OR ELEVATED SURFACES BUT WILL REMAIN CLOSE TO A TENTH OR TWO. REST
OF THE AREA WILL REMAIN LIQUID. TEMPERATURES WERE TRICKY AS MODEL
BLENDS AND CONSENSUS DROPS AREAS NORTH AND WEST OF THE
AFOREMENTIONED LINE TO AROUND 30 DEGREES BY FRIDAY MORNING.
HOWEVER...INFLUX OF LOW-LEVEL MOISTURE AND INCREASED CLOUD COVER
SHOULD KEEP TEMPERATURES WARMER THAN WHAT GUIDANCE HAS AND OPTED
TO GO 33-34 DEGREES AS OPPOSED TO 30-32 IN THIS REGION.
TEMPERATURES OUTSIDE OF THIS AREA OF CONCERN WILL BE IN THE UPPER
30S TO LOWER 40S WHICH WILL RESULT IN ALL LIQUID PRECIPITATION.

JORDAN

LONG TERM...
THE STORM SYSTEM DISCUSSED IN THE SHORT TERM SECTION WILL BE
TRANSLATING OVER THE REGION ON FRIDAY. THE LATEST NWP TRENDS ARE A
BIT SHARPER WITH THE UPPER TROUGH AND THUS WITH THE LARGE SCALE
FORCING AS THE WAVE PASSES. IN TURN...MOST GUIDANCE GENERATES AT
LEAST SCATTERED LIGHT QPF ACROSS THE SOUTH PLAINS FRIDAY
MORNING...WITH SOME HINTS AT POSSIBLE BANDING THAT COULD LOCALLY
ENHANCE PRECIPITATION RATES. THESE BANDED FEATURES ARE SUPPORTED BY
TIME-HEIGHT CROSS-SECTIONS SHOWING NARROW LAYERS OF EPV NEAR OR
SLIGHTLY BELOW ZERO WITH EVEN MINIMAL ELEVATED CAPE AVAILABLE IN A
FEW POCKETS. GIVEN THIS...WE CAN NOT DISCOUNT THE POSSIBILITY OF A
FEW BANDED CONVECTIVE FEATURES...PERHAPS EVEN A RUMBLE OF
THUNDER...THOUGH THE UPRIGHT INSTABILITY IS PROGGED TO BE RATHER
MEAGER AND WE HAVE LEFT THE THUNDER MENTION OUT OF THE GRIDS.
HOWEVER...GIVEN THE EXPECTED GREATER LIFT /VERSUS WHAT WAS PROGGED
24 HOURS AGO/ AND POTENTIAL FOR A FEW BANDED ELEMENTS...WE HAVE GONE
AHEAD AND RAISED POPS BACK INTO THE CHANCE CATEGORY FOR A GOOD CHUNK
OF THE CENTRAL AND EASTERN ZONES FRIDAY MORNING WHILE MAINTAINING A
MINIMAL MENTION ACROSS THE WEST. IT APPEARS A CHILLY RAIN WILL BE
THE PREDOMINATE PRECIPITATION MODE. THE LATEST PROGGED SOUNDINGS
EVEN SUGGEST THE NORTHWEST ZONES MAY STAY JUST WARM ENOUGH TO KEEP
THE P-TYPE LIQUID...BUT WITH THE THREAT FOR A FEW HEAVIER
BANDS...WOULD NOT BE SURPRISED TO SEE THE ADDED DYNAMIC COOLING PULL
THE TEMPERATURE PROFILE DOWN ENOUGH FOR A LITTLE SNOW TO MIX
IN...AS ALLUDED TO IN THE SHORT TERM SECTION. HENCE...A RAIN/SNOW
MIX WAS MAINTAINED OVER THE SOUTHWEST TEXAS PANHANDLE AND NORTHERN
SOUTH PLAINS FRIDAY MORNING. THE PRECIPITATION WILL SHIFT EASTWARD
THROUGH THE DAY...THOUGH IT COULD LINGER INTO THE AFTERNOON HOURS
OFF THE CAPROCK...BEFORE MOVING EAST OF THE CWA BY EVENING.
LINGERING CLOUD COVER /PARTICULARLY ACROSS THE EASTERN ZONES/ WILL
RESULT IN A COOL DAY...WITH TEMPERATURES LIKELY NOT MAKING IT
ABOVE THE MIDDLE 40S IN THE ROLLING PLAINS...THOUGH LOCATIONS NEAR
THE TX/NM LINE MAY ECLIPSE THE 50 DEGREE MARK.

BRIEF AND LOW-AMPLITUDE SHORTWAVE RIDGING WILL FOLLOW FRIDAY/S STORM
SYSTEM BEFORE THE NEXT UPPER TROUGH RACES PAST LATE SATURDAY INTO
SUNDAY. THIS WAVE WILL BE DEVOID OF DEEP MOISTURE AND THUS SHOULD BE
A DRY PASSAGE. A MORE SIGNIFICANT UPPER LOW IS THEN FORECAST TO FORM
ACROSS THE MIDWEST EARLY NEXT WEEK AND THEN EDGE EASTWARD INTO THE
GREAT LAKES BY THE MIDDLE OF THE WEEK. THIS WILL PUT WEST TEXAS
UNDER NORTHWEST FLOW ALOFT. A FEW EMBEDDED DISTURBANCES MAY TRAVERSE
THE REGION WITHIN THIS NORTHWEST FLOW...BUT THEY WILL HAVE LITTLE
MOISTURE TO WORK ON...SO OCCASIONAL INCREASES IN CLOUD COVER APPEAR
THE MOST LIKELY BET...THOUGH AN ISOLATED LIGHT SHOWER IS NOT OUT OF
THE QUESTION. REGARDLESS...THE PROSPECT OF ANY MEANINGFUL
PRECIPITATION IS TOO LOW TO INCLUDE IN THE FORECAST AT THIS POINT.

TEMPERATURES SHOULD RECOVER TO NEAR OR SLIGHTLY ABOVE AVERAGE THIS
WEEKEND AS SOUTHERLY TO WESTERLY SURFACE FLOW DEVELOPS. MONDAY COULD
BE EVEN WARMER...THOUGH THIS IS IN QUESTION NOW WITH THE LATEST
ECMWF BRINGING A DECENT COLD FRONT /ASSOCIATED WITH THE
DEVELOPING UPPER LOW WELL TO THE NORTH/ THROUGH DURING THE
DAY...INSTEAD OF DELAYING IT UNTIL MONDAY EVENING. IN EITHER
CASE...TEMPERATURES WILL DROP BACK TOWARD AVERAGE BEHIND THIS
FRONT INTO THE MIDDLE OF NEXT WEEK. ALTHOUGH BEYOND THE SCOPE OF
THIS FORECAST...IT IS INTERESTING TO NOTE THAT THE MEDIUM RANGE
GUIDANCE DOES CONTINUE TO ADVERTISE A MUCH STRONGER COLD FRONT
MOVING THROUGH WEST TEXAS TOWARD THE END OF NEXT WEEK. IT WILL BE
SOMETHING TO KEEP AN EYE ON MOVING INTO THE THE HOLIDAY WEEKEND.

&&

.PRELIMINARY POINT TEMPS/POPS...
FRIONA        49  33  48  23  53 /   0  30  10   0   0
TULIA         48  34  46  26  54 /   0  30  30   0   0
PLAINVIEW     51  35  46  28  54 /   0  30  30   0   0
LEVELLAND     56  34  49  26  55 /   0  30  20   0   0
LUBBOCK       55  36  47  29  55 /   0  30  30   0   0
DENVER CITY   59  37  52  27  56 /   0  40  20   0   0
BROWNFIELD    58  36  49  28  55 /   0  40  20   0   0
CHILDRESS     49  37  45  31  54 /   0  30  30  10   0
SPUR          57  35  45  30  55 /   0  30  30  10   0
ASPERMONT     59  39  47  32  56 /   0  40  40  10  10

&&

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

$$

07

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.