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000
FXUS64 KLIX 281406
AFDLIX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
906 AM CDT MON JUL 28 2014

...SOUNDING DISCUSSION...
A FAIRLY MOIST COLUMN UP TO 700MB WITH THE EXCEPTION OF A BIT OF
DRYING AROUND THE 950MB LEVEL ON THIS MORNING/S SOUNDING. OTHER
NOTABLE FEATURES ARE THE DRY AIR ABOVE 700MB WHICH COULD MIX DOWN
IN AFTERNOON THUNDERSTORMS AND PRODUCE STRONG TO SEVERE WIND
GUSTS. THIS IS SUPPORTED WITH DOWNDRAFT CAPE VALUES AROUND 950
J/KG. PRECIPITABLE WATER VALUES OF 1.90 MEAN THAT LOCALLY HEAVY
RAIN IS POSSIBLE. THERE IS ALSO A WARM TEMPERATURE LAYER FROM
700MB TO ABOUT 650MB. AS FOR INSTABILITY...THERE IS A GOOD AMOUNT
WITH MLCAPE VALUES CALCULATED AROUND 1400 J/KG. WHILE THERE IS
CAPE IN THE 0 TO -20C HAIL GROWTH ZONE...THERE IS NOT MUCH
MOISTURE THERE SO HAIL THREAT SEEMS QUITE LOW. THE FREEZING LEVEL
IS AROUND 17000 FEET. WINDS WERE FROM THE WEST UP TO 700MB AND
THEN LIGHT IN THE MID LEVELS AND THEN FROM THE NORTH IN THE UPPER
LEVELS. THE MAXIMUM WIND SPEED OF 26 KNOTS WAS LOCATED AT ABOUT
1000 FEET ABOVE THE GROUND. STATS ON THIS MORNING/S SUCCESSFUL
BALLOON LAUNCH ARE THAT IT BURST OVER LAKE PONTCHARTRAIN AT A
HEIGHT OF 20.7 MILES ABOVE THE GROUND.

ANSORGE

&&

.PREV DISCUSSION... /ISSUED 426 AM CDT MON JUL 28 2014/

SHORT TERM...
A QUIET OVERNIGHT PERIOD WITH ONLY A FEW CLOUDS AROUND EARLY THIS
MORNING. A COLD FRONT IS JUST OFF TO THE NORTH MAKING ITS WAY INTO
NORTH CENTRAL MISSISSIPPI AND SOUTHERN ARKANSAS. THIS FRONT WILL
BE THE MAIN PLAYER IN THE FORECAST THIS WEEK. OVER THE LAST HOUR
OR SO STORMS HAVE DEVELOPED OVER SOUTHERN ARKANSAS. MESOSCALE
MODELS HAVE SHOWN THIS TO BE THE CASE OVER THE LAST FEW RUNS...AND
GOING OFF OF THAT THE TREND IS FOR THUNDERSTORMS TO CONTINUE TO
DEVELOP AS THE FRONT SAGS SOUTHWARD. IF THIS IS THE CASE WE SHOULD
EXPECT SCATTERED SHOWERS AND THUNDERSTORMS THIS AFTERNOON ACROSS
THE ENTIRE FORECAST AREA. THE ATMOSPHERE IS CONDUCIVE FOR
THUNDERSTORMS AS THE ATMOSPHERE IS UNSTABLE...WE HAVE A LIFTING
MECHANISM IN THE FRONT...AND WE HAVE PLENTY OF MOISTURE AROUND AS
PRECIPITABLE WATER VALUES ARE EXPECTED TO BE IN THE 1.90 TO 2.10
RANGE THIS AFTERNOON. ALL OF THE INGREDIENTS ARE THE BASICS FOR
THUNDERSTORM DEVELOPMENT. SOME OF THESE STORMS THIS AFTERNOON
COULD BE ON THE STRONG TO SEVERE SIDE AND WITH THAT THE STORM
PREDICTION CENTER STILL MAINTAINS A SLIGHT RISK OF SEVERE WEATHER
MAINLY ACROSS THE MISSISSIPPI GULF COASTAL COUNTIES INTO PORTIONS
OF ST. TAMMANY PARISH. THESE THUNDERSTORMS COULD PRODUCE STRONG
DAMAGING WIND GUSTS...FREQUENT LIGHTNING STRIKES...HAIL...AND
LOCALLY HEAVY DOWNPOURS. THE FRONT WILL CONTINUE TO PUSH THROUGH
THE AREA THROUGH TONIGHT. 13/MH

LONG TERM...
THE FRONT SHOULD MAKE IT COMPLETELY THROUGH THE FORECAST AREA AND
SHOULD CLEAR THE COASTAL WATERS BEFORE STALLING. MODELS STILL
INSIST ON KEEPING BOUNDARY IN THE NORTHERN PORTIONS OF THE GULF
BEFORE DRAWING NORTHWARD TOWARDS THE END OF THE WEEK. AN UPPER
IMPULSE EJECTS FROM THE WEST THAT WILL LIKELY INDUCE A WAVE UPON
THE SURFACE FRONT OVER EAST TEXAS TO RAPIDLY DESTABILIZE THE
REGION THURSDAY AND FRIDAY. SO WEDNESDAY AND EARLY THURSDAY SHOULD
BE A DRY PERIOD PRIOR TO RETURNING TO A WET PATTERN LATE THURSDAY
INTO THE WEEKEND. 13/MH

AVIATION...
THUNDERSTORM COVERAGE WILL BE A LITTLE MORE TODAY AND EACH TERMINAL
SHOULD BE VISITED BY A FEW OR AT LEAST NEARBY. SCATTERED TO BROKEN
CIGS WILL MOVE FROM AROUND 020 UP TO 050 BY THIS EVENING.

MARINE...
AN APPROACHING UPPER LEVEL TROUGH AND ASSOCIATED COLD FRONT WILL
KEEP WINDS GENERALLY SOUTH TO SOUTHWEST WITH SPEEDS RANGING MAINLY
FROM AROUND 8-16 KNOTS AND SEAS AROUND 3 FEET AS A WEAK BUT UNUSUAL
SUMMERTIME COLD FRONT APPROACHES THE COASTAL WATERS EARLY TUESDAY.
NORTHEAST WINDS WILL EVENTUALLY DEVELOP EARLY WEDNESDAY BUT THE
FRONT WILL QUICKLY LOSE ITS INTEGRITY AS IT MOVES FARTHER OUT INTO
THE GULF OF MEXICO. A WEAK PRESSURE PATTERN WILL KEEP WINDS LIGHT
AND MORE VARIABLE THE REMAINDER OF THE FORECAST PERIOD.

DECISION SUPPORT...
DSS CODE...YELLOW.
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  93  67  89  65 /  40  40  10  10
BTR  94  71  91  68 /  40  40  20  10
ASD  94  72  91  69 /  40  40  10  10
MSY  93  76  90  74 /  50  40  20  10
GPT  94  73  91  70 /  50  50  10  10
PQL  94  72  90  68 /  50  50  10  10

&&

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

$$