Area Forecast Discussion
Issued by NWS New Orleans/Baton Rouge, LA

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FXUS64 KLIX 280940
AFDLIX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
340 AM CST FRI NOV 28 2014

.SHORT TERM...

NO SIGNIFICANT CHANGES IN THINKING FROM THE PREVIOUS FORECAST FOR
THE REMAINDER OF THE THANKSGIVING WEEKEND. AN UPPER LEVEL RIDGE
WILL CONTINUE TO BUILD OVER THE AREA AND SHOULD BE CENTERED ON TOP
OF THE GULF SOUTH SATURDAY INTO SATURDAY NIGHT. WITH STRONG
SUBSIDENCE IN PLACE THROUGHOUT THE ATMOSPHERIC COLUMN...THERE WILL
BE NO CHANCE OF PRECIPITATION DEVELOPING THROUGH SUNDAY. THE
RIDGING AND RESULTANT SINKING AIR ALOFT WILL ALSO KEEP THE MID AND
UPPER LEVELS WARM AND DRY THROUGH THE PERIOD. THIS WARMING WILL
ALSO TRANSLATE DOWN TO THE LOW LEVELS...WITH READINGS RISING TO
SLIGHTLY WARMER THAN NORMAL LEVELS FOR SATURDAY AND SUNDAY. IN THE
LOW LEVELS...ONSHORE FLOW WILL ALSO DEVELOP WILL ALLOW FOR GULF
MOISTURE TO ADVECT BACK INTO THE REGION. DEWPOINTS WILL RISE BACK
INTO THE MIDDLE TO UPPER 50S BY SATURDAY AFTERNOON AND REMAIN AT
THIS LEVEL THROUGH THE REMAINDER OF THE WEEKEND. WITH WATER
TEMPERATURES IN THE NEARSHORE WATERS IN THE UPPER 50S...AND
WEAKENING BOUNDARY LAYER FLOW LATE SATURDAY NIGHT AND SUNDAY
NIGHT...CONDITIONS LOOK MORE FAVORABLE FOR SOME ADVECTION FOG TO
DEVELOP. HAVE INCLUDED A MENTION OF PATCHY FOG FOR BOTH NIGHTS IN
THE NEARSHORE WATERS AND ADJACENT COASTLINE.

.LONG TERM...

EARLY NEXT WEEK...BOTH THE EURO AND THE GFS ARE PICKING UP ON A
WEAK AND FAST MOVING SHORT WAVE FEATURE MOVING FROM THE PLAINS
INTO THE MIDWEST. THIS WEAK FEATURE WILL DRIVE A FRONTAL BOUNDARY
INTO THE LOWER MISSISSIPPI VALLEY ON MONDAY. AS THE UPPER LEVEL
SUPPORT BEHIND THE FRONT SHIFTS TO THE EAST...THE FRONT WILL
GRADUALLY STALL OVER THE NORTHWEST PORTION OF THE CWA MONDAY
AFTERNOON INTO MONDAY NIGHT AND DISSIPATE BY TUESDAY MORNING. HAVE
KEPT IN A CHANCE FOR SOME SHOWERS TO DEVELOP NEAR THE FRONT FROM
MONDAY INTO MONDAY EVENING. AS THE FRONT WASHES OUT AND OVERALL
OMEGA DECREASES...RAIN CHANCES WILL DIMINISH ON TUESDAY. THERE
WILL ALSO BE A CONTINUED THREAT OF ADVECTION FOG TO IMPACT AREAS
ALONG THE COAST AND IN THE NEARSHORE WATERS MONDAY NIGHT AS
TEMPERATURES AND DEWPOINTS REMAIN ELEVATED IN THIS AREA.

INCREASING NEGATIVE VORTICITY ADVECTION ASSOCIATED WITH A RIDGE
BUILDING INTO THE GULF OF MEXICO WILL TAKE HOLD OF THE AREA
TUESDAY AND CONTINUE INTO WEDNESDAY. WITH INCREASED SUBSIDENCE AND
DRIER AIR IN PLACE...EXPECT TO SEE DRY WEATHER FOR BOTH TUESDAY
AND WEDNESDAY. ALTHOUGH BOTH MODELS SHOW THIS RIDGING
DEVELOP...THE GFS HAS A MUCH STRONGER RIDGE IN PLACE OVER THE
CENTRAL GULF BY MID-WEEK THAN THE EURO SUGGESTS. ON THE NORTHERN
PERIPHERY OF THE RIDGE...A ZONAL FLOW PATTERN WILL DOMINATE THE GULF
SOUTH.  ANY SENSIBLE WEATHER WILL BE DRIVEN BY WEAK SHORT WAVE
IMPULSES RIDING ALONG THE NORTHERN PERIPHERY OF THE RIDGE. IF THE
GFS IS CORRECT...MOST OF THIS ENERGY WILL REMAIN WELL NORTH OF THE
CWA...RESULTING IN A MOSTLY DRY AND WARMER FORECAST FOR THE LATTER
HALF OF THE WEEK. IF THE EURO IS CORRECT...THAN A RISK OF AT LEAST
ISOLATED SHOWERS AND SLIGHTLY COOLER TEMPERATURES EXISTS FOR
THURSDAY AND FRIDAY.  ONE TREND TO NOTE IS THAT THE EURO HAS LEANED
MORE TOWARD THE GFS THE LAST FEW RUNS...AND THIS LENDS MORE WEIGHT
TO THE GFS SOLUTION. THUS...POPS ARE SLIGHTLY BIASED MORE TOWARD
THE GFS OR DRIER SOLUTION FOR THURSDAY AND FRIDAY. HAVE OPTED TO GO
WITH A 10-15 PERCENT CHANCE OF RAIN FOR THE LATTER HALF OF THE
WEEK ALONG WITH PARTLY TO MOSTLY CLOUDY SKIES. THE BLEND ALSO
RESULTS IN NEAR NORMAL TEMPERATURES FOR THE LATTER HALF OF THE
WEEK. OVERALL...CONFIDENCE IS HIGH THAT THE RIDGE WILL BE OVER THE
GULF...BUT RAIN CHANCES WILL BE HIGHLY DEPENDENT ON THE OVERALL
STRENGTH OF THE RIDGE AND CONFIDENCE IS LOWER ON THAT.

&&

.AVIATION...

VFR CAVU CONDITIONS EXPECTED ALL TERMINALS NEXT 24-30 HOURS. WINDS WILL
BE VEERING NE-SE AT LIGHT LEVELS THROUGH 12Z SAT. 24/RR

&&

.MARINE...

WINDS WILL BE RELAXING TODAY AS HIGH PRESSURE RIDGE SETTLES ACROSS THE
GULF STATES. WINDS WILL BE VEERING TO PREDOMINANTLY EASTERLY FLOW
THROUGHOUT THE DAY AND SOUTHEAST OVER THE WEEKEND. NEXT FRONTAL SYSTEM ON
MONDAY SHOULD STALL INLAND OF THE COAST BUT RELAX THE WIND FIELD WHILE
BULKING LOW LEVEL MOISTURE ENOUGH FOR POTENTIAL SEA FOG CONSIDERATIONS
IN THE NEAR SHORE WATERS AND TIDAL LAKES/BAYS MONDAY NIGHT AND TUESDAY
MORNING. 24/RR

&&

.DECISION SUPPORT...

DSS CODE...GREEN.
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  60  44  71  54 /   0   0   0   0
BTR  62  48  72  56 /   0   0  10   0
ASD  60  44  71  55 /   0   0   0   0
MSY  61  51  72  59 /   0   0   0   0
GPT  57  48  70  56 /   0   0   0   0
PQL  58  41  70  55 /   0   0   0   0

&&

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

$$

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