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000
FXUS64 KTSA 062251
AFDTSA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
451 PM CST FRI DEC 6 2013

.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
FOR THE 0Z TAFS... LIGHT SNOW IS ENDING ACROSS NORTHWEST ARKANSAS
AT THIS TIME AND WILL NOT BE CARRIED PAST 0Z IN THE TAFS. MVFR
CEILINGS AND VISIBILITIES WILL PERSIST A WHILE LONGER AT ARKANSAS
SITES AND PERHAPS INTERMITTENTLY AT EASTERN OKLAHOMA SITES BEFORE
THE ENTIRE AREA CLEARS OUT LATER TONIGHT. THERE WILL BE A SLIGHT
POSSIBILITY THAT FREEZING FOG COULD FORM TOWARD MORNING OVER THE
SNOW PACK AT OUR ARKANSAS SITES... OTHERWISE VFR CONDITIONS WILL
PREVAIL AT ALL SITES FOR THE REMAINDER OF THE FORECAST PERIOD.


&&

.PREV DISCUSSION... /ISSUED 328 PM CST FRI DEC 6 2013/

DISCUSSION...

LOOKING ALOFT ON WV IMAGERY...THE SHORTWAVE TROUGH THAT BROUGHT
THE WINTRY WEATHER IS NOW QUICKLY LIFTING OUT TO THE NORTHEAST OF
OUR AREA THIS AFTERNOON...AND THE STORM HAS ENDED. HOWEVER...THE
WESTERN CONUS TROUGH REMAINS IN PLACE...AND ANOTHER SHORTWAVE
TROUGH NOW DROPPING DOWN THE WEST COAST WILL LIFT OUT INTO THE
PLAINS THIS WEEKEND. AT THE SURFACE...A GIANT ARCTIC ANTICYCLONE
LIES FROM WESTERN CANADA DOWN INTO THE NORTH CENTRAL CONUS. NORTH
WINDS WILL CONTINUE ACROSS OUR REGION TO THE SOUTH OF THE
HIGH...GRADUALLY BACKING OFF WITH TIME TONIGHT. SKIES WILL
CLEAR...AND THE WINDS MAY GO LIGHT ENOUGH IN THE USUAL COOL
VALLEYS TO ALLOW TEMPS TO DROP TO NEAR OR BELOW ZERO TONIGHT.
FORECAST WIND SPEEDS ARE EXPECTED TO REMAIN JUST BELOW THE 10 MPH
SUSTAINED THRESHOLD FOR A WIND CHILL ADVISORY...SO I HAVE ELECTED
TO NOT ISSUE THE HEADLINE AND WILL PASS THIS ON TO THE NEXT SHIFT
TO MONITOR.

MID LEVEL ISENTROPIC LIFT GETS GOING BY LATE SATURDAY AHEAD OF THE
AFOREMENTIONED WAVE...AND MODELS ARE NOW SHOWING SOME LIGHT QPF
IN THE SOUTH SO I HAVE ELECTED TO INSERT SLGT CHC POPS SATURDAY
AFTERNOON AND SPREAD THOSE NORTHEAST SATURDAY NIGHT. MODEL
SOUNDINGS SUGGEST THAT AS WE GO INTO SUNDAY THE COLUMN DRIES OUT
ALOFT AS THE WARM CONVEYOR SHIFTS EAST AND THE DRY INTRUSION WORKS
ITS WAY IN FROM THE SOUTHWEST. THIS WOULD SUGGEST THAT SOME PATCHY
FREEZING DRIZZLE IS POSSIBLE JUST ABOUT ANYWHERE SUNDAY. THE
EXCEPTION TO THIS MAY BE ACROSS THE FAR NORTH...WHERE POSITIVE PV
ADVECTION CLOSER TO THE EJECTING SHORTWAVE MAY PRODUCE ENOUGH LIFT
TO BRIEFLY SATURATE THE COLD MID LEVELS AND PRODUCE SOME BRIEF
LIGHT WINTRY PRECIP. I REITERATE LIGHT HERE FOLKS...THERE WILL NOT
BE NEAR AS MOISTURE FOR THIS SYSTEM TO WORK WITH. THIS SYSTEM
QUICKLY LIFTS NORTHEAST SUNDAY NIGHT AND THE LIFT SHUTS OFF. A
REINFORCING SHOT OF ARCTIC AIR WILL PUSH INTO THE REGION BEHIND
THIS SYSTEM.

THE HIGHLY AMPLIFIED UPPER PATTERN OVER THE WESTERN 2/3RDS OF NORTH
AMERICA IS FORECAST TO BREAK DOWN NEXT WEEK...AND THE WESTERN
TROUGH WILL FINALLY LIFT OUT ACROSS THE PLAINS. LIKE THE PREVIOUS
SHIFT MENTIONED...SOME FLURRIES ARE POSSIBLE DUE TO THE STRONG PV
ADVECTION ALOFT...BUT A SERIOUS LACK OF MOISTURE PRECLUDES ME FROM
PUTTING ANYTHING IN THE FORECAST ATTM. TEMPS WILL ALSO MODERATE
BECAUSE OF THIS...AND WE WILL BE ABLE TO THAW SOME LATER IN THE
WEEK.

THE PATTERN WILL BE LESS AMPLIFIED AND MORE PROGRESSIVE LATE IN
THE PERIOD...AND A COUPLE WEAKER SYSTEM WILL TRAVERSE ACROSS THE
SOUTHERN TIER OF STATES LATE IN THE WEEK. LIFT AHEAD OF THESE
SYSTEMS WILL BRING A CHANCE FOR PRECIP...SOME POSSIBLY
WINTRY...TOWARD THE END OF THE PERIOD...ALTHOUGH THIS DOES NOT LOOK
SERIOUS.

LACY

&&

.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&

$$

SHORT TERM...99
LONG TERM....99
AVIATION...06