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000
FXUS64 KLIX 080957
AFDLIX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
357 AM CST SAT MAR 8 2014

.SYNOPSIS...BROAD HIGH PRESSURE AT THE SFC CONTINUES TO DOMINATE THE
SERN CONUS AND ERN 2/3RDS OF THE GULF WITH BROAD AREA OF HIGH
PRESSURE PUSHING SOUTH OUT OF CNTRL CANADA INTO THE NRN AND CNTRL
PLAINS. WEAK LOW PRESSURE IS NOTED OVER THE TX BIG BEND/WRN TX. A
WEAK COLD FRONT STRETCHES FROM QUEBEC OVER THE GRT LAKES THROUGH THE
MID MS VALLEY AND INTO THE SRN PLAINS WHERE IT IS MAINLY A
STATIONARY FRONT FROM THE SRN PLAINS INTO THE AREA OF LOW PRESSURE
OVER WRN TX. IN THE MID LVL A STRONG S/W IS NOTED MOVING INTO THE
DESERT SW WITH THE TROUGH AXIS STRETCHING NORTHEAST THROUGH THE FOUR
CORNERS AND INTO THE CNTRL PLAINS. RIDGE WAS OVER THE SERN CONUS
WITH THE RIDGE AXIS LOCATED FROM THE NERN GULF THROUGH THE
APPALACHIANS. /CAB/

&&

.SHORT TERM...MOSTLY QUIET NIGHT OVER THE REGION WITH HIGH CLOUDS
LEADING TO A MOSTLY CLOUDY SKIES. A FEW LOCATIONS MAINLY CLOSE TO
THE COAST HAVE SEEN VISIBILITIES DROP BUT NO WIDESPREAD FOG ISSUES.
TEMPS HAVE FALLEN INTO THE 40S OVER THE ENTIRE CWA AND WILL CONTINUE
TO DROP ANOTHER FEW DEGREES THIS MORNING BEFORE SUNRISE.

TODAY WILL BE QUIET AS HIGH PRESSURE CONTINUES TO SLIDE EAST AND THE
RIDGE OVER THE SERN CONUS FLATTENS OUT. WE WILL SEE TEMPS ABOUT 10
TO 15 DEGREES WARMER TODAY AS H925 TEMPS WARM SOME 5-7 DEGREES C (TO
AROUND 10-12C) FROM YESTERDAY MORNING. THIS SUGGESTS HIGHS IN THE
UPPER 60S TO LOWER 70S BUT WITH CLOUDS LIKELY HANGING AROUND HIGHS
SHOULD GENERALLY RANGE FROM THE MID TO UPPER 60S TODAY.

TONIGHT AND TOMORROW WE MAY START TO SEE SOME SPOTTY SHOWER
ACTIVITY. FIRST THE WEAK AREA OF LOW PRESSURE AT THE SFC IN WRN TX
THIS MORNING WILL PUSH EAST THROUGH THE DAY TODAY AND INTO WRN LA.
IT WILL FILL IN SOME BUT THIS WILL ALSO DRAW THAT WEAK COLD FRONT
INTO THE LOWER MS VALLEY AND CLOSE TO OUR CWA. AT THE SAME TIME WE
WILL BEGIN TO MOVE UNDER SW FLOW AS THE S/W OVER THE DESERT SW
CONTINUES TO DIG SOUTH INTO MEXICO AND THE SRN PLAINS. THIS WILL
SEND A WEAK IMPULSE ACROSS THE REGION TONIGHT AND AS THIS COMBINES
WITH THE SLIGHTLY BETTER LL CONVERGENCE FROM THE APPROACHING FRONT
ISLTD SHRA ARE NOT OUT OF THE QUESTION TONIGHT. AS FOR TOMORROW THE
BEST CHANCE SHRA WILL BE THROUGH THE MORNING AND INTO MIDDAY. THE
FRONT SHOULD QUICKLY BEGIN TO RETREAT BACK TO THE NORTH SUN WITH
WEAK HIGH PRESSURE TAKING BACK OVER ALONG THE N-CNTRL AND NERN GULF
THUS DIMINISHING WHAT LL CONVERGENCE WE DID HAVE. AS FOR
TEMPS...MORNING LOWS SUN WILL BE A GOOD BIT WARMER THANKS TO
INCREASING LL MOISTURE BUT AFTN HIGHS WILL GENERALLY BE SIMILAR TO
TODAYS WITH HIGHS MAINLY RANGING FROM THE UPPER 60S TO NEAR 70.

SUN NIGHT AND MON...TEMPS WILL BE A TAD WARMER THAN SUN WITH MORNING
LOWS MAINLY IN THE LOWER TO MID 50S AND HIGHS IN THE LOWER TO MID
70S. SUN NIGHT SHOULD REMAIN FAIRLY DRY BUT THIS SHOULD BE THE LAST
PERIOD OF DRY WEATHER UNTIL WED. ON MON THE DISTURBANCE (NOW A
CLOSED LOW) THAT HAS DUG INTO MEXICO WILL START TO LIFT ACROSS
MEXICO MON AND INTO SRN TX IN RESPONSE TO ANOTHER STRONG DISTURBANCE
WORKING SE OUT OF THE PAC NW. WITH THE LOW IN SRN TX IT WILL START
TO INCREASE THE SW FLOW OVER OUR AREA MON WITH BETTER LIFT OVER THE
REGION. THIS IN COMBINATION WITH A DEVELOPING SFC LOW IN THE WRN
GULF AND INCREASING MOISTURE WILL LEAD TO SHRA DEVELOPING MON BUT
BETTER RAIN CHANCES WILL BE ON THE WAY MON NIGHT AND TUE.

.LONG TERM...MDLS CONTINUE TO COME INTO BETTER AGREEMENT WITH THE
LOW OVER TX NOT PHASING WITH THE PAC NW DISTURBANCE LATER IN THE
WEEK AND THUS BRINGING TWO SEPARATE SYSTEMS ACROSS THE CONUS. THAT
SAID THERE ARE STILL SOME DIFFERENCES WITH THE RESPECT TO TUES
SYSTEM. AFTER THAT THE MEDIUM RANGE MDLS SHOW THINGS COOLING DOWN
FOR THE SECOND HALF OF THE WEEK WITH DRIER CONDITIONS. WILL USE A
BLEND OF THE MDLS IN THE EXTENDED WITH A SLIGHTLY HIGHER WEIGHT
TWRDS THE GFS FOR THE TUE SYSTEM DUE TO ITS BETTER CONSISTENCY.

THE MAIN CONCERN IN THE EXTENDED IS TUE AND INTO TUE NIGHT. THE
BIGGEST DIFFERENCE BETWEEN THE GFS AND ECMWF WITH THIS TIME FRAME IS
THE INFLUENCE OF A S/W THAT BROKE OFF FROM THE MAIN DISTURBANCE THAT
IS CURRENTLY DIGGING TWRDS MEXICO. BOTH MDLS HAVE THIS PIECE BUT THE
GFS STARTS TO PUSH IT EAST FASTER WITH THE MAIN LOW MOVING EAST
ACROSS SRN AND INTO THE NRN GULF. THE ECMWF IS SLOWER WITH THAT WEAK
S/W WHICH DRAWS THE CLOSED LOW FURTHER NORTH AND MERGES TOGETHER
ONSHORE OVER ERN TX AND WRN LA. THE EVENTUAL TRACK OF THE CLOSED LOW
WILL LEAD TO THE DEVELOPMENT OF THE WRN GULF LOW AND WHERE IT
TRACKS. LITTLE SHIFTS COULD LEAD TO SIGNIFICANT DIFFERENCES OVER OUR
AREA WITH RESPECT TO CONVECTION...WHETHER WE WILL HAVE JUST
SHRA...ISLTD TSRA...SCT TO WIDESPREAD TSRA WITH EVEN A RISK OF
STRONG TO SVR WEATHER. AGAIN WE ARE LEANING TWRDS THE GFS DUE TO ITS
CONSISTENCY AND THIS WOULD KEEP THE SFC LOW MAINLY OVER OUR COASTAL
WATERS THUS KEEPING MUCH OF THE AREA IN THE COLD SECTOR. INSTABILITY
WILL BE MINIMAL BUT THERE SHOULD BE AT LEAST ISLTD TSRA ACROSS MUCH
OF THE AREA...BEST CHANCE ALONG THE COAST. ANY SHIFT NORTH WILL LEAD
TO A BETTER CHANCE FOR TSRA.

THE LOW WILL PUSH EAST ACROSS THE GULF COAST STATES TUE NIGHT WITH
DRIER AIR PUSHING IN WED BUT THE COLDER AIR WILL HOLD OFF UNTIL WED
NIGHT AS A LARGE ARA OF HIGH PRESSURE WORKS SOUTH THROUGH THE PLAINS
AND INTO THE SRN PLAINS AND LOWER MS VALLEY. /CAB/

&&

.MARINE...
PRESSURE GRADIENT OVER THE COASTAL WATERS IS QUITE WEAK AT THE
MOMENT WITH SURFACE RIDGE CENTERED RIGHT OVER THE NORTH CENTRAL GULF
OF MEXICO. THIS HIGH WILL SHIFT EASTWARD AND MEANDER OVER THE
SOUTHEASTERN UNITED STATES THIS WEEKEND THROUGH EARLY NEXT WEEK.
WINDS WILL THUS REMAIN LIGHT AT 10 KNOTS OR LESS WITH GENERALLY AN
ONSHORE DIRECTION. STILL SOME UNCERTAINTY WITH SYSTEM NEXT WEEK.
MODELS INDICATE THAT A SURFACE LOW WILL DEVELOP IN THE NORTHWESTERN
GULF AND THEN TRACK EASTWARD ACROSS THE GULF COAST. ITS LATITUDE
COULD BE ANYWHERE FROM SOUTHWEST MISSISSIPPI TO NORTHERN GULF OF
MEXICO. A STRONG COLD FRONT WILL MOVE IN MID WEEK AFTER THIS SYSTEM
PASS.  SMALL CRAFT ADVISORY CONDITIONS COULD DEVELOP THEN.

MEFFER
&&

.AVIATION...
MOSTLY HIGH CLOUDS WILL CONTINUE TO STREAM ACROSS THE CENTRAL GULF
COAST REGION TODAY. THERE WILL BE SOME MAINLY LIGHT FOG THAT WILL
PRODUCE A FEW HOURS OF MVFR TO POSSIBLY IFR CONDITIONS AROUND
SUNRISE. ANY VSBY RESTRICTIONS SHOULD BE OVER BY 13-14Z...THEN A
SURGE OF LOW LEVEL MOISTURE WILL PRODUCE SOME SCT-BKN DECKS 020-030
FROM ABOUT MID MORNING THROUGH THE AFTERNOON AND EVENING.

&&

.DECISION SUPPORT...
DSS CODE...BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT.


DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN  = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE   = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
         VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
         WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
         TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED    = FULL ENGAGEMENT FOR MODERATE TO HIGH RISK SVR
         AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
         SIGNIFICANCE

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  69  51  69  51 /   0  30  30  10
BTR  69  53  70  52 /  10  30  30  10
ASD  69  52  69  53 /  10  20  30  10
MSY  68  54  69  56 /  10  20  30  10
GPT  66  53  69  54 /  10  10  20  10
PQL  67  49  70  51 /  10  10  20  10

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&

$$

SHORT/LONG TERM: CAB
AVIATION/MARINE: MEFFER