Area Forecast Discussion
Issued by NWS

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

Skip product version selection by date and time.   

510
FXUS64 KLUB 211750
AFDLUB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LUBBOCK TX
1150 AM CST FRI NOV 21 2014

.AVIATION...
UPPER LOW LOWER COLORADO VALLEY AT 18Z WILL MOVE TO JUST WEST OF
THE TEXAS BIG BEND BY 18Z SATURDAY. FLOW WILL BACK WITH APPROACH
OF THIS LOW ALLOWING MOISTURE TO INCREASE LATER TODAY AND TONIGHT.
MODEST LIFT AND INSTABILITY WILL BEGIN TO OVERSPREAD KLBB DURING
THE NIGHT...AND KCDS LATE TONIGHT THROUGH SATURDAY MORNING. KLBB
LOOKS LIKE ON BORDERLINE WITH CHANCE OF THUNDER...BETTER CHANCE
TO THE EAST...SO WILL HOLD OFF ON A TEMPO OR PROB MENTION. PERHAPS
A HIGHER CHANCE OF LIGHT SHOWERS OR DRIZZLE THOUGH WHICH WILL NEED
ADDITIONAL ASSESSMENT. RETAINED PREVIOUS TEMPO THUNDER FOR KCDS
LATER TONIGHT INTO SATURDAY MORNING. MUST ALSO BE MENTIONED THAT
THE STORM PREDICTION CENTER HAS INDICATED A MARGINAL SEVERE RISK
FOR KCDS WITH LARGE HAIL THE MAIN CONCERN. BUT THE INITIAL PROBLEM
WILL BE A RISK FOR LIFR CEILINGS BY MID EVENING FOR BOTH SITES...
WHICH HAS BEEN EXPLICITLY MENTIONED. CANNOT RULE OUT GOING DOWN
HARD ON VISIBILITY FROM DENSE FOG AS WELL THOUGH CONFIDENCE NOT AS
HIGH. MENTION OF LIGHT FOG ONLY FOR NOW. STRATUS LAYER CURRENTLY
OVER KCDS APPEARS STARTING NOW TO BE SLOWLY ERODING FROM THE WEST
AND SOUTHWEST AS A HIGH LEVEL IMPULSE AND THICKER CLOUDS ALOFT
CLEAR AWAY. EXPECT IMPROVEMENT AT KCDS WITHIN THE NEXT HOUR OR TWO
BEFORE RETURNING BY MID-EVENING. RMCQUEEN

&&

.PREV DISCUSSION... /ISSUED 931 AM CST FRI NOV 21 2014/

UPDATE...
MID MORNING UPDATE FOR MORE EXTENSIVE CLOUD COVER AND ALSO
PERSISTENT FOG IN PARTS OF ROLLING PLAINS. RMCQUEEN

AVIATION...
KCDS HAS GONE DOWN HARD IN THE PAST HALF HOUR AS STRATUS LAYER HAS
MOVED IN. LATEST HRRR AND RAP SHORT TERM GUIDANCE INDICATE GOOD
CHANCE THIS WILL BE PERSISTENT LATE INTO THE MORNING. STRATUS
LAYER SOUTH OF KLBB...MEANTIME...HAS NOT MADE IT FAR ENOUGH NORTH
AND WE HAVE AMENDED KLBB TO REMOVE MENTION. RMCQUEEN

PREV DISCUSSION... /ISSUED 525 AM CST FRI NOV 21 2014/

AVIATION...
MVFR FOG AND IFR CLOUD DECKS WERE NOTED EAST OF KCDS EARLY THIS
MORNING...AND SLOWLY NEARING THE TAF SITE. SOME COMPUTER MODELS
ARE PESSIMISTIC IN THIS ACTIVITY MAKING IT TO KCDS GIVE A
NORTHWEST WIND HAS BECOME ESTABLISHED. HOWEVER...CURRENT TRENDS MAY
SEE OTHERWISE. HAVE THEREFORE INSERTED A SCT BELOW 1000 FT AGL DECK
AND MVFR FOG UNTIL LATE MORNING. LOW CLOUDS WELL SOUTH OF KLBB
GRADUALLY MOVING NORTHEAST VALIDATES AN INSERTION OF A FEW IFR DECK.
WILL OF COURSE AMEND AS NECESSARY. OTHERWISE...LIGHT AND VARIABLE
NORTH WINDS WILL VEER TO THE SOUTHEAST THIS AFTN. INCREASING VFR
DECKS WILL PASS OVERHEAD TOWARDS THE EVENING HOURS WHILE AN
APPROACHING UPPER LEVEL DISTURBANCE AIDS IN THE DEVELOPMENT OF
-TSRA. ONCE AGAIN...KCDS IS MOST FAVORED FOR STORM CHANCES AND HAVE
INSERTED A TEMPO COMMENCING LATE TONIGHT/EARLY TOMORROW MORNING.
COMPUTER MODELS HINT AT MVFR CLOUD DECKS MAKING A RETURN TOMORROW
EVENING.

PREV DISCUSSION... /ISSUED 245 AM CST FRI NOV 21 2014/

SHORT TERM...
A WEAK EMBEDDED DISTURBANCE IN THE NEAR ZONAL FLOW ALOFT...PASSED
ACROSS THE SOUTHERN PLAINS YESTERDAY AFTN/EVENING...THUS RESULTING
IN A NRLY WIND SHIFT WHICH PREVAILED EARLY THIS MORNING. AN AREA OF
STRATUS AND FOGGY CONDITIONS WERE NOTED ACROSS ERN TEXAS THIS
MORNING...AND COULD APPROACH THE FAR ROLLING PLAINS AOA SUNRISE AS
HINTED AT BY MODEL SOLUTIONS. HOWEVER IT MAY BE HARD-PRESSED TO
AFFECT THE SAID AREA GIVEN PROGGED SFC WINDS BACKING TO THE NW WHICH
IS NOT A FAVORABLE WIND COMPONENT THAT ENCOURAGES THE INCREASE OF
LOW LEVEL MOISTURE. NONETHELESS...WOULD NOT BE SURPRISED IF A FEW
LOCALES ACROSS THE FAR ROLLING PLAINS EXPERIENCE FOG AND/OR LOW
CLOUDS BEFORE IT SCOURS OUT BY MID-LATE MORNING. WILL THEREFORE
MAINTAIN A FOG MENTION ACROSS THE ROLLING PLAINS WITH THIS FORECAST
PACKAGE.

ATTENTION QUICKLY TURNS TO AN UA LOW THAT IS TRANSLATING ESE ACROSS
CNTRL/SRN CALI PER 08Z WATER VAPOR IMAGERY. FORECAST SOLUTIONS TRACK
THE DISTURBANCE ACROSS THE NRN BAJA THIS AFN...TO NWRN OLD MEXICO
BY THE END OF THE SHORT TERM PERIOD. MEANWHILE...THE WEAK SFC
BOUNDARY WILL HAVE WASHED OUT AND SFC WINDS WILL VEER TO THE S-SE
THUS AIDING IN TRANSPORTING GULF MOISTURE ACROSS THE REGION. IT IS
NO WONDER THAT PROGGED PWATS INCREASE TO 0.5 INCH-1.20 INCHES BY
TONIGHT...WITH HIGHEST PWATS OCCURRING OFF THE CAPROCK. AS THE
SYSTEM DRAWS NEAR TONIGHT...UL SUPPORT WILL BE ON THE INCREASE
ESPECIALLY OFF THE CAPROCK...AND THE LLJ WILL CRANK UP TO 25-35
KTS ACROSS THE SAID AREA. AN APPROACHING DISTURBANCE COUPLED WITH
A MOISTENING ATMOSPHERE AND AN INCREASING LLJ WILL RESULT IN
THUNDERSTORM CHANCES COMMENCING LATE THIS EVENING INTO
TONIGHT...WITH HIGHEST POPS OFF THE CAPROCK. AS PWATS RISE ABOVE
1.00 INCH...WILL NEED TO BE ON THE LOOK OUT FOR PERIODS OF
MODERATE-HEAVY RAINFALL. FURTHERMORE...CAN NOT OVERLOOK PROGGED
MID-LEVEL CAPE VALUES OF 1.0-1.5 KJ/KG...0-6 KM BULK SHEAR VALUES
AOA 40 KTS AND VEERING WIND PROFILES NOTED FOR AREAS OFF THE
CAPROCK...THUS SUGGESTING STORMS HAVING THE CAPABILITY OF
APPROACHING STRONG LEVELS WITH HAIL BEING THE PRIMARY THREAT.

THE APPROACHING UA LOW WILL CAUSE LOWERING 500 MB HEIGHT FIELDS AND
HENCE SLIGHTLY COOLER DAYTIME TEMPS...THOUGH STILL NEAR SEASONAL
NORMS /LOWER TO MIDDLE 60S/. OVERNIGHT LOWS WILL RANGE FROM THE
UPPER 30S ACROSS THE FAR SW TX PANHANDLE TO THE LOWER 50S ACROSS THE
LOW ROLLING PLAINS.

LONG TERM...
SHOWERS AND THUNDERSTORMS LIKELY ONGOING AT THE BEGINNING OF
SATURDAY PER THE DISCUSSION ABOVE. MAJORITY OF THE MODEL SOLUTIONS
KEEP AN OPEN AND PROGRESSIVE WAVE MOVING ACROSS WEST TEXAS WHICH
WILL CONTINUE TO FAVOR THE ROLLING PLAINS FOR PRECIPITATION
SATURDAY MORNING AND A POSSIBILITY OF SHOWERS LINGERING INTO THE
AFTN HOURS THERE. PREVIOUS FCST HANDLES WELL WITH ONLY SOME MINOR
MODIFICATION TO THE PRECIP RELATED FIELDS.

HEIGHT GRADIENT PROGGED TO TIGHTEN BEHIND THE DEPARTING UPPER
TROUGH AND AHEAD OF A LOW-AMPLITUDE TROUGH MOVING SEWD ACROSS THE
ROCKIES SATURDAY NIGHT. AS THAT WAVE MOVES CLOSER TO THE AREA
SUNDAY...PROGGED 700MB HEIGHTS AND WIND SPEEDS SUGGEST A PERIOD OF
WINDY CONDITIONS DURING THE MORNING AND POSSIBLY INTO THE
AFTERNOON HOURS FAVORING THE SWRN THIRD OF THE FCST AREA.
INCREASING MID LEVEL CLOUD COVER AHEAD OF THE WAVE AND A FRONT
MOVING INTO THE FCST AREA ARE EXPECTED TO LIMIT WIND SPEEDS BELOW
ADVISORY LEVELS.

REMAINDER OF THE FCST PERIOD LOOKS FAIRLY QUIET WITH THE SRN HIGH
PLAINS UNDERNEATH NWLY FLOW ALOFT AS A RIDGE WILL BE ANCHORED
ACROSS THE WRN CONUS AND A TROUGH TO THE EAST. MODELS SEEM TO BE
CONVERGING ON A SOLUTION OF THE RIDGE BEGINNING TO SHIFT EAST
TOWARD THE PLAINS AND COLD AIR SPILLING INTO MUCH OF THE ERN CONUS
WITH THE POSSIBILITY OF SOME OF THAT COLD AIR BACKING INTO THE
AREA BRIEFLY AROUND THURSDAY. THIS IS TRENDING AWAY FROM A MORE
PRONOUNCED COLD AIR MASS MOVING INTO THE AREA PER SOME PREVIOUS
RUNS...MOST NOTABLY THE ECMWF.

&&

.PRELIMINARY POINT TEMPS/POPS...
FRIONA        64  38  66  36  54 /   0  10  10   0  10
TULIA         63  41  66  38  57 /   0  20  20  10  10
PLAINVIEW     63  43  66  39  59 /   0  20  20  10   0
LEVELLAND     64  43  66  40  61 /   0  30  20  10   0
LUBBOCK       65  45  66  41  62 /   0  30  30  10   0
DENVER CITY   67  45  66  43  65 /   0  30  20  10   0
BROWNFIELD    65  45  66  42  63 /   0  30  30  10   0
CHILDRESS     60  46  64  43  64 /   0  60  60  10   0
SPUR          64  46  66  43  65 /   0  60  60  10   0
ASPERMONT     64  50  67  47  69 /  10  80  80  10   0

&&

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

$$

99/99/05

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