421
FXUS64 KLIX 151228
AFDLIX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
728 AM CDT SAT JUN 15 2013

.SOUNDING DISCUSSION...

FLIGHT PROGRESSING WELL THIS MORNING. FRONTAL BOUNDARY OBVIOUSLY
STILL SOUTH OF US AS SOUNDING REMAINS RATHER DRY WITH THE MINOR
EXCEPTION OF A MOIST LAYER BETWEEN 3000-5000 FEET. THIS WAS
REFLECTED IN A LAYER OF CLOUDS AT LAUNCH TIME. THESE CLOUDS WERE
UNDER AN INVERSION OF ABOUT 4C. LIFTED INDEX ONLY -0.5 THIS
MORNING. AIRMASS WILL NEED QUITE A BIT OF MODIFICATION BEFORE
CONVECTION OCCURS.

&&

.PREV DISCUSSION... /ISSUED 303 AM CDT SAT JUN 15 2013/

SYNOPSIS...

SURFACE HIGH PRESSURE REMAINS ANCHORED OVER THE CENTRAL GULF OF
MEXICO. A FRONTAL BOUNDARY LINGERS ALONG THE SOUTHEAST LOUISIANA
COAST. OTHER THAN A COUPLE OF STRAY THUNDERSTORMS OVER THE GULF
WELL TO THE SOUTH OF SOUTHWEST PASS...NO PRECIPITATION NOTED OVER
THE AREA. NORTH OF LAKE PONTCHARTRAIN...TEMPERATURES ARE A LITTLE
COOLER THIS MORNING THAN THE LAST SEVERAL MORNINGS WITH READINGS
BETWEEN 70 AND 75. DEW POINTS IN THIS AREA ARE RUNNING BETWEEN 65
AND 70. TO THE SOUTH OF THE LAKE...TEMPERATURES ARE IN THE UPPER
70S AND LOWER 80S WITH DEW POINTS IN THE MID 70S ONCE ONE GETS
SOUTH OF NEW ORLEANS.

SHORT TERM...

UPPER RIDGING OVER THE AREA WILL REMAIN IN PLACE FOR ABOUT ANOTHER
24 HOURS. NORTH OF THE BOUNDARY...THE AIRMASS IS RATHER DRY AS
OBSERVED ON 00Z SOUNDINGS HERE AND AT JACKSON...WHERE PRECIPITABLE
WATER VALUES WERE NEAR ONE INCH. ON THE OTHER HAND...SOUTH OF THE
BOUNDARY...AS SEEN IN THE LAKE CHARLES SOUNDING...PW VALUES ARE
MUCH CLOSER TO 2 INCHES. ANY CONVECTIVE DEVELOPMENT TODAY WILL BE
VERY ISOLATED...AND PRIMARILY RESTRICTED TO THE COASTAL WATERS.
AFTERNOON TEMPERATURES ARE EXPECTED TO REACH THE LOWER AND MIDDLE
90S AGAIN...BUT WITH LOWER HUMIDITY VALUES TODAY...HEAT INDEX
VALUES SHOULD REMAIN BELOW ADVISORY CRITERIA.

AS SHORTWAVES TRAVERSE THE MIDDLE MISSISSIPPI VALLEY AND OHIO
VALLEY...UPPER RIDGE GETS SUPPRESSED SOUTHWARD INTO THE GULF
BEGINNING SUNDAY. MOISTURE RETURNS AS NOTED BY INCREASING
PRECIPITABLE WATER VALUES ON BUFR FORECAST SOUNDINGS. NAM SOUNDINGS
WOULD INDICATE WARM TEMPERATURES NEAR 700 MB MAY CAP
CONVECTION...GFS SOUNDINGS INDICATE NO CAP. WILL CARRY 20-30
PERCENT RAIN CHANCES FOR SUNDAY AND MONDAY AFTERNOONS. WITH
ADDITIONAL CLOUDINESS AND CHANCES FOR RAIN...AFTERNOON HIGH
TEMPERATURES WILL BE CLOSE TO NORMAL. 35

$$

LONG TERM...

PATTERN CHANGES LITTLE FOR WEDNESDAY AND THURSDAY...WITH AFTERNOON
CONVECTIVE DEVELOPMENT ANTICIPATED BOTH DAYS. MEDIUM RANGE MODELS
ARE CONSISTENT WITH ATTEMPTING TO BUILD UPPER RIDGE BACK INTO THE
AREA NEXT FRIDAY OR SATURDAY...WHICH WOULD LOWER RAIN CHANCES NEXT
WEEKEND. LITTLE DAY TO DAY VARIATION IN TEMPERATURES IS
ANTICIPATED...WITH READINGS NEAR OR SLIGHTLY ABOVE NORMAL. 35

AVIATION...

VFR CONDITIONS ARE GENERALLY EXPECTED THROUGH 12Z SUNDAY. KHUM MAY
SEE A BRIEF PERIOD MVFR CONDITIONS DUE TO LIGHT FOG EARLY THIS
MORNING. IN ADDITION...A FEW OF THE MORE FOG TERMINALS MAY SEE A
PERIOD MVFR CONDITIONS DUE TO LIGHT FOG EARLY SUNDAY MORNING. 11

MARINE...

A WEAK FRONTAL BOUNDARY DRAPED NEAR THE SOUTHEAST LOUISIANA
COASTLINE WILL BECOME DIFFUSE TODAY. HIGH PRESSURE WILL REBUILD OVER
THE NORTH GULF THROUGH THE EARLY PART OF NEXT WEEK. GENERALLY LIGHT
WINDS OF 10 KNOTS OR LESS WILL PREVAIL THROUGH MID WEEK WITH SEAS OF
2 FEET OR LESS. 11

DECISION SUPPORT...

DSS CODE...BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT.
             SUPPORTING GEISMER CHEMICAL PLANT EXPLOSION SITE.
             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  93  71  91  71 /  10  10  20  10
BTR  94  74  93  72 /  10  10  20  10
ASD  91  74  91  73 /  10  10  20  10
MSY  92  77  90  75 /  10  10  20  10
GPT  90  75  89  74 /  10  10  30  10
PQL  91  71  90  71 /  10  10  30  20

&&

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

$$