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791
FXUS64 KLIX 170836
AFDLIX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
336 AM CDT FRI MAY 17 2013

.SHORT TERM...

INCREASING NEGATIVE VORTICITY ADVECTION AND SUBSIDENCE IN THE MID
TO UPPER LEVELS WILL TAKE PLACE THROUGH THE DAY AS AN UPPER LEVEL
LOW CURRENTLY OVER THE MID-MISSISSIPPI VALLEY PULLS TO THE EAST.
BY TONIGHT...STRONG RIDGING WILL BE IN PLACE ACROSS THE FORECAST
AREA. THIS RIDGING WILL DOMINATE THE REGION THROUGH THE REMAINDER
OF THE WEEKEND. AS A RESULT...EXPECT TO SEE WARMER TEMPERATURES
AND NO PRECIPITATION CHANCES THROUGH SUNDAY. HIGHS WILL WARM INTO
THE UPPER 80S AND LOWER 90S EACH DAY...AND OVERNIGHT LOWS WILL
COOL INTO THE UPPER 60S AND LOWER 70S. OVERALL...THESE READINGS
WILL BE VERY CLOSE TO THE SEASONAL NORMS EXPECTED FOR MID TO LATE
MAY. THERE WILL BE SOME STRATUS DEVELOPING DURING THE OVERNIGHT
HOURS EACH NIGHT...DUE TO THE DEVELOPMENT OF AN ELEVATED
INVERSION. THESE CLOUDS WILL TEND TO FORM AROUND MIDNIGHT AND
BREAK INTO A SCATTERED STRATOCU FIELD BY MID-MORNING EACH DAY.

.LONG TERM...

HEADING INTO NEXT WEEK...STRONG RIDING WILL CONTINUE TO DOMINATE
THROUGH TUESDAY. SEASONABLY WARM TEMPERATURES AND VERY LOW CHANCES
OF RAIN WILL CONTINUE. HOWEVER...THE RIDGE WILL BEGIN TO WEAKEN
AND SHIFT TOWARD THE EASTERN SEABOARD ON WEDNESDAY AS A FAIRLY
STRONG SHORTWAVE TROUGH SWINGS THROUGH THE PLAINS STATES AND INTO
THE MIDWEST. THE STRONGEST DYNAMICS AND FORCING WILL REMAIN WELL
NORTH OF THE FORECAST AREA WITH THIS SYSTEM...BUT A WEAK FRONTAL
BOUNDARY SHOULD SLIDE INTO THE NORTHERN HALF OF THE FORECAST AREA
BY WEDNESDAY NIGHT. SLIGHT COOLING ALOFT WILL ALLOW FOR INCREASED
OVERALL INSTABILITY IN THE REGION. WITH AMPLE WARMTH AND MOISTURE
IN PLACE...THERE WILL BE THE POTENTIAL FOR SOME ISOLATED
CONVECTION TO DEVELOP IN THE VICINITY OF THE LOW LEVEL FRONTAL
BOUNDARY WEDNESDAY AFTERNOON. THIS INITIAL FRONT WILL WASH OUT
OVER THE AREA BY THURSDAY MORNING.  ANY CONVECTION WILL BE
DIURNAL IN NATURE...AND SHOULD DISSIPATE SHORTLY AFTER SUNSET.


ON THURSDAY AND FRIDAY...AN UPPER LEVEL RIDGE WILL BEGIN
TO BUILD BACK INTO THE AREA. HOWEVER...THE LOW AND MID-LEVEL RIDGE
WILL BE CENTERED OVER THE MID-MISSISSIPPI VALLEY. NORTHEAST FLOW
IN THE LOW TO MID-LEVELS WILL PUSH A WEAK FRONT DOWN FROM THE
NORTH AND EAST ON THURSDAY. ALTHOUGH OVER FORCING WILL BE VERY
LIMITED ALOFT...THERE SHOULD BE ENOUGH LIFT ALONG THE BOUNDARY TO
SPARK OFF SOME ISOLATED CONVECTION THURSDAY INTO THURSDAY NIGHT.
HAVE WENT WITH SLIGHT CHANCE POPS TO REFLECT THIS RISK.
TEMPERATURES WILL REMAIN NEAR SEASONAL AVERAGES THROUGH THE END OF
THE WEEK. 32

&&

.AVIATION...

MOSTLY MVFR CONDITIONS WILL PREVAIL DUE TO CIGS THROUGH ABOUT 15Z
TODAY WITH A FEW AIRPORTS LIKELY TO HAVE A PERIOD OF IFR. VFR
CONDITIONS WILL RETURN BY LATE MORNING. ANY SHRA/TSRA ARE EXPECTED
TO REMAIN TOO ISOLATED TODAY FOR MENTION IN THE TAFS. LOWER CIGS AND
POSSIBLY SOME MINOR VSBY RESTRICTIONS WILL LEAD TO ANOTHER PERIOD OF
MVFR TO IFR CONDITIONS STARTING AROUND 05Z/MIDNIGHT TONIGHT AND
PERSISTING THROUGH MID MORNING ON SATURDAY. 22/TD

&&

.MARINE...

UPPER LEVEL LOW PRESSURE SYSTEM OVER THE INLAND PORTION OF THE LOWER
MISSISSIPPI VALLEY IS MAINTAINING SOME SLIGHTLY HIGHER SOUTHEAST TO
SOUTH WINDS AROUND 15 KNOTS AT MANY LOCATIONS...AND 3 TO 4 FEET SEAS
EARLY THIS MORNING. THIS UPPER LEVEL SYSTEM WILL PULL AWAY FROM THE
REGION TODAY WHICH WILL SLACKEN THE SURFACE PRESSURE GRADIENT AND
ALLOW WINDS TO EASE TO 10 TO 15 KNOTS TODAY AND EARLY TONIGHT AND
AROUND 10 KNOTS LATE TONIGHT THROUGH SUNDAY MORNING. A SURFACE HIGH
PRESSURE RIDGE EXTENDING FROM THE ATLANTIC TO THE GULF COAST REGION
WILL PERSIST THROUGH THE MIDDLE OF NEXT WEEK. SOUTHEAST TO SOUTH
WINDS FROM AROUND 10 KNOTS TO 10 TO 15 KNOTS WILL PERSIST SUNDAY
AFTERNOON THROUGH EARLY NEXT WEEK WITH SEAS MAINLY IN THE 2 TO 3
FEET RANGE. 22/TD

&&

.DECISION SUPPORT...
DSS CODE...BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT.
             MONITORING RIVER FLOODING.

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  85  68  88  68 /  10  10  10  10
BTR  87  69  89  69 /  10  10  10  10
ASD  84  69  85  70 /  10  10  10  10
MSY  85  71  86  71 /  10  10  10  10
GPT  82  69  83  71 /  10  10  10  10
PQL  83  67  83  71 /  10  10  10  10

&&

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

$$

32