FXUS64 KLZK 081132
AFDLZK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LITTLE ROCK AR
532 AM CST TUE DEC 8 2009
.AVIATION...
LIFR CONDITIONS WERE PRESENT ACROSS ALL TAF SITES THIS MORNING.
SCATTERED SHOWERS ARE EXPECTED TO CONTINUE ACROSS THE STATE
TODAY...WITH ISOLATED THUNDERSTORMS DEVELOPING ACROSS THE
SOUTHEAST CORNER OF THE STATE. RAIN WILL COME TO AN END TUESDAY
EVENING...WITH WINDS PICKING UP ACROSS THE AREA. WIND SPEEDS WILL
BE 10 TO 15 KTS WITH GUST FROM 20 TO 25 KTS.
&&
.PREV DISCUSSION... /ISSUED 333 AM CST TUE DEC 8 2009/
SHORT TERM...TUESDAY THROUGH FRIDAY
WESTERN CONUS SHORTWAVE TROF ALREADY CLEARLY VISIBLE ON MOISTURE
CHANNEL IMAGERY THIS MORNING. SURFACE CYCLOGENESIS ALSO UNDERWAY AND
SYSTEM FORECAST TO EVOLVE INTO A MAJOR EARLY SEASON EVENT FOR THE
CENTRAL PLAINS AND UPPER MIDWEST. GFS/ECMWF/NAM REMAIN IN DECENT
AGREEMENT WITH THE EVOLUTION OF THIS SYSTEM AND ALL CONTINUE TO
ADVERTISE A RAINFALL EVENT FOR THE FORECAST AREA. NAM JUST A TAD
FASTER LIFTING THE SURFACE LOW OUT AND FEEL THE BEST COURSE OF
ACTION THIS MORNING IS TO GO WITH A GFS/ECMWF COMPROMISE.
LATEST SURFACE ANALYSIS PLACES WARM FRONTAL BOUNDARY ALONG THE GULF
COAST WITH FEATURE EXPECTED TO MOVE NORTHWARD THROUGH THE DAY.
MODELS INDICATE THE BOUNDARY GETS AS FAR NORTH AS THE EXTREME
SOUTHEAST CORNER OF THE FORECAST AREA. ITS IN THIS AREA WHERE THE
BEST CHANCES OF THUNDERSTORMS WILL EXIST BUT CHANCES OF SEVERE
WEATHER LOOK LOW ALTHOUGH ISOLATED STRONG STORMS CAN BE RULED OUT.
WARM AIR ADVECTION ALREADY UNDERWAY AND TEMPERATURES EXPECTED TO
REMAIN STEADY OR POSSIBLY RISE A DEGREE OR TWO THROUGH THE REMAINDER
OF THE NIGHT. LIGHT PRECIPITATION ALREADY BREAKING OUT IN THE WARM
AIR ADVECTION AND PRECIPITATION EXPECTED TO BECOME WIDESPREAD AS THE
DAY PROGRESSES.
MODELS CONSISTENT IN MOVING AFOREMENTIONED SHORTWAVE TROF EASTWARD
TO THE CENTRAL PLAINS BY EARLY THIS EVENING AS IT BECOMES NEGATIVELY
TILTED. SYSTEM RACES OFF TO THE NORTH BY WEDNESDAY MORNING WHERE IT
UNDERGOES RAPID DEEPENING. SURFACE LOW ALSO INTENSIFIES RAPIDLY AS
IT MOVES THROUGH THE CENTRAL PLAINS AND EVENTUALLY INTO THE GREAT
LAKES BY EARLY WEDNESDAY.
MODELS HAVE ALL BUT RULED OUT ANY WINTER PRECIPITATION ALTHOUGH
BUFKIT DATA/MODEL SOUNDINGS CONTINUE TO INDICATE SOME SNOW POSSIBLE
ON THE BACK SIDE. WILL NOT INCLUDE ANY WINTER PRECIPITATION IN THE
FORECAST RIGHT NOW AS COLD AIR ARRIVES AFTER MOISTURE HAS EXITED BUT
A FEW STRAY FLURRIES CAN NOT BE RULED OUT.
MAIN BULK OF THE PRECIPITATION WILL FALL THROUGH EARLY AFTERNOON AS
MODELS SHOW SOME DRY SLOTTING LATER IN THE DAY. PRECIPITATION WILL
NOT TOTALLY END UNTIL STRONG COLD FRONT MOVES THROUGH WEDNESDAY
NIGHT. FRONTAL SYSTEM WILL BE FOLLOWED BY STRONG COLD AIR ADVECTION
AS ARCTIC HIGH PRESSURE WILL BEGIN TO MOVE INTO THE REGION. STRONG
PRESSURE GRADIENT DEVELOPS BETWEEN THE DEPARTING LOW AND ADVANCING
HIGH. TOSS IN SOME JET DYNAMICS AND A LAKE WIND ADVISORY WILL BE
HOISTED FOR TONIGHT THROUGH WEDNESDAY AFTERNOON.
HIGH PRESSURE WILL DOMINATE WEDNESDAY AND THURSDAY BEFORE SLIDING
OFF TO THE EAST BY FRIDAY MORNING. UPPER FLOW WILL BRING A WEAK
SHORTWAVE TO THE AREA LATE FRIDAY BUT DISTURBANCE FURTHER SOUTH THAN
PREVIOUS RUNS. WILL HOLD OFF ON PRECIPITATION CHANCES UNTIL LATER IN
THE DAY AFTER TEMPERATURES HAVE WARMED ABOVE FREEZING ACROSS MOST OF
THE AREA WITH SOUTHERLY FLOW RETURNING. WILL REWORK WEATHER GRIDS
HERE TO KEEP PRECIPITATION ALL LIQUID EXCEPT POSSIBLY OVER THE FAR
NORTH.
MODELS INDICATING TEMPERATURES WILL CONTINUE TO RUN BELOW NORMAL
THROUGH THE PERIOD. MAV/MEX NUMBERS LOOK REASONABLE AND ARE
GENERALLY ACCEPTED.
LONG TERM...FRIDAY NIGHT THROUGH MONDAY
SOUTHWEST FLOW WILL BE OVER THE AREA TO START THE LONG TERM. MUCH
DISAGREEMENT EXISTS IN THE SOLUTIONS FOR THE EXTENDED PERIOD. THE
GFS HAS A SYSTEM OVER THE STATE AT THE BEGINNING OF THE
PERIOD...WITH THE ECMWF HOLDING THE SYSTEM OFF UNTIL SATURDAY.
LEANED MORE TOWARDS THE GFS...WITH PRECIPITATION CHANCES CONTINUING
THROUGH SATURDAY EVENING. TEMPERATURES LOOK TO BE COLD ENOUGH
SATURDAY MORNING TO SUPPORT A RAIN/SNOW MIX OVER THE NORTH. MODEL
TIMING AND PLACEMENT ISSUES CONTINUE INTO THE BEGINNING OF THE WEEK.
WILL CONTINUE TO MONITOR FUTURE MODEL RUNS TO GET A BETTER HANDLE ON
THE LONG TERM. TEMPERATURES ARE EXPECTED TO BE BELOW NORMAL ON
SATURDAY...WARMING TO NEAR NORMAL LEVELS FOR THE REMAINDER OF THE
PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR 49 34 39 20 / 100 50 10 0
CAMDEN AR 57 38 45 25 / 90 50 0 0
HARRISON AR 47 29 34 18 / 100 40 10 0
HOT SPRINGS AR 53 36 42 23 / 90 40 0 0
LITTLE ROCK AR 53 36 42 23 / 100 50 10 0
MONTICELLO AR 59 39 46 25 / 100 50 0 0
MOUNT IDA AR 52 36 40 22 / 90 30 0 0
MOUNTAIN HOME AR 47 31 36 19 / 100 40 10 0
NEWPORT AR 51 35 41 21 / 100 50 10 0
PINE BLUFF AR 56 38 45 25 / 100 50 0 0
RUSSELLVILLE AR 50 34 38 20 / 90 40 10 0
SEARCY AR 51 36 41 22 / 100 50 10 0
STUTTGART AR 55 37 44 24 / 100 50 10 0
&&
.LZK WATCHES/WARNINGS/ADVISORIES...
LAKE WIND ADVISORY FROM 9 PM THIS EVENING TO 4 PM CST WEDNESDAY
FOR ARKANSAS-BAXTER-BOONE-BRADLEY-CALHOUN-CLARK-CLEBURNE-
CLEVELAND-CONWAY-DALLAS-DESHA-DREW-FAULKNER-FULTON-GARLAND-GRANT-
HOT SPRING-INDEPENDENCE-IZARD-JACKSON-JEFFERSON-JOHNSON-LINCOLN-
LOGAN-LONOKE-MARION-MONROE-MONTGOMERY-NEWTON-OUACHITA-PERRY-PIKE-
POLK-POPE-PRAIRIE-PULASKI-SALINE-SCOTT-SEARCY-SHARP-STONE-VAN
BUREN-WHITE-WOODRUFF-YELL.
&&
$$
AVIATION...60
