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977
FXUS64 KLIX 030531
AFDLIX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
1131 PM CST SAT MAR 2 2013

.AVIATION...
VFR CONDITIONS WILL PREVAIL AT ALL TERMINALS WITH CLEAR SKIES AND
NORTHWEST WINDS GENERALLY 10 KTS OR LESS. MAIN EXCEPTIONS WILL BE
KMSY AND KNEW...WHERE WINDS WILL REMAIN STRONGER THROUGH THE
REMAINDER OF TONIGHT.

&&

.PREV DISCUSSION... /ISSUED 749 PM CST SAT MAR 2 2013/

SOUNDING DISCUSSION...

NO PROBLEMS WITH THE FLIGHT THIS EVENING. A VERY DRY AND STABLE
SOUNDING WITH A PW OF ONLY 0.35 INCHES AND AN LI OF 11.6. A STRONG
NORTHWESTERLY FLOW IN THE LOWER TO MIDDLE LEVELS WITH A MODERATE
WESTERLY FLOW ALOFT. A VERY COLD AIR MASS IN PLACE WITH 850 MB
TEMPERATURES AT 17 DEGREES FAHRENHEIT.

PREV DISCUSSION... /ISSUED 425 PM CST SAT MAR 2 2013/

SHORT TERM...
FREEZING TEMPERATURES ARE ON TRACK AS FORECAST THE
LAST COUPLE DAYS...PROVIDED THE BACK EDGE OF THE LOW CLOUD DECK
CONTINUES TO ADVANCE WEST THIS EVENING AND CLEAR OUT THE EASTERN
ZONES BY MIDNIGHT. THE FORECAST LOWS HAVE CONVERTED THE FREEZE
WATCH TO A FREEZE WARNING FOR THE SAME TIME AND AREA. THE LOWS
TONIGHT WILL BE VERY CLOSE THE COLDEST READINGS WE HAVE SEEN THIS
YEAR...BUT NOT AT HARD FREEZE CRITERIA. A MODERATE FREEZE TO BRIEF
HARD FREEZE IS EXPECTED OVER THE FAR NORTH/NORTHEAST AREA WITH A
FAIRLY LONG DURATION OF SUB-FREEZING TEMPERATURES. SOUTH OF LAKE
PONTCHARTRAIN...THE FREEZING OR LOWER TEMPERATURES WILL MAINLY BE
CONFINED TO THE WEST BANK AREAS OF METRO NEW ORLEANS THROUGH THE
RIVER PARISHES DOWN TO NEAR HOUMA...BUT THE FREEZE SHOULD BE
BRIEF. NORTHERLY WINDS OFF LAKE PONTCHARTRAIN WILL KEEP THE EAST
BANK AREAS MOSTLY IN THE MID 30S FOR THE LOWS WITH SOME FROST
POSSIBLE.

THE MID/UPPER TROUGH WILL MOVE EAST ACROSS THE EASTERN CONUS
TONIGHT AND SUNDAY WHILE THE UPPER RIDGE MOVES FROM THE WESTERN
STATES INTO THE PLAINS. THE PATTERN WILL BE DEAMPLIFYING DURING
THE PERIOD. SURFACE HIGH PRESSURE WILL BUILD OVER THE FORECAST
AREA LATE TONIGHT AND SUNDAY MORNING ALLOWING IDEAL RADIATIONAL
COOLING ACROSS SOUTHWEST AND SOUTH CENTRAL MISSISSIPPI INTO EAST
CENTRAL AND SOUTH CENTRAL LOUISIANA. A LINGERING SLIGHT PRESSURE
GRADIENT AND WIND WILL KEEP SOME MIXING GOING MOST OF THE NIGHT
ACROSS AREAS SOUTH OF LAKE PONTCHARTRAIN INTO COASTAL MISSISSIPPI
SO THE CONFIDENCE IS A BIT LOWER FOR REACHING THE FORECAST LOWS.
SKIES WILL BE SUNNY ON SUNDAY WHICH WILL ALLOW THE HIGHS TO REACH
THE MID TO UPPER 50S...STILL QUITE COOL FOR EARLY MARCH.

AS THE HIGH MOVES EAST...LOW PRESSURE AND ASSOCIATED COLD FRONT
WILL MOVE INTO THE CENTRAL/SOUTHERN PLAINS ON MONDAY WHICH WILL
CAUSE STRONGER SOUTHERLY WINDS TO DEVELOP ALONG WITH MUCH WARMER
TEMPERATURES BY LATE MORNING AND AFTERNOON WITH PARTLY TO MOSTLY
SUNNY SKIES.

LONG TERM...

THE WARMER WEATHER WILL CONTINUE UNTIL THE NEXT STRONG COLD FRONT
MOVES THROUGH TUESDAY. THERE WILL BE A SLIGHT CHANCE TO LOW CHANCE
OF SHOWERS ASSOCIATED WITH THIS FRONT TUESDAY INTO EARLY TUESDAY
EVENING...BUT THERE DOES NOT APPEAR TO BE ENOUGH INSTABILITY TO
SUPPORT ANY THUNDERSTORMS. COLDER AIR WILL BE NOTICEABLE AGAIN
TUESDAY NIGHT INTO WEDNESDAY WEDNESDAY NIGHT BEFORE WARMER AIR
GRADUALLY RETURNS THURSDAY THROUGH SATURDAY. SURFACE HIGH PRESSURE
WILL DOMINATE WHILE MOVING SLOWLY EAST ACROSS THE AREA WEDNESDAY
THROUGH SATURDAY.

MARINE...

COLD AIR ADVECTION AND STRONG PRESSURE GRADIENT WITH BUILDING HIGH
PRESSURE WILL RESULT IN BREEZY NORTHERLY WINDS AND SMALL CRAFT
ADVISORY CONDITIONS ACROSS ALL WATERS EXCEPT LAKES PONTCHARTRAIN
AND MAUREPAS TONIGHT AND EARLY SUNDAY MORNING. HAVE ADDED LAKE
BORGNE AND THE MISSISSIPPI SOUND TO THE SMALL CRAFT ADVISORY WHERE
WINDS HAVE ALREADY BEEN CLOSE TO CRITERIA.

CENTER OF HIGH PRESSURE WILL MOVE EAST ACROSS THE FORECAST AREA ON
SUNDAY. THIS WILL RESULT IN DIMINISHING WINDS AND SEAS IN THE
AFTERNOON AND EVENING. HIGH PRESSURE WILL MOVE EAST SUNDAY NIGHT
AND MONDAY AS LOW PRESSURE AND THE NEXT COLD FRONT DEVELOP/MOVE
INTO THE CENTRAL/SOUTHERN PLAINS. TIGHT PRESSURE GRADIENT WILL
CAUSE SOUTHERLY WINDS WILL RISE TO NEAR SMALL CRAFT CRITERIA OVER
WESTERN WATERS BY MIDDAY MONDAY AND THESE STRONGER WINDS WILL
PERSIST INTO MOST OF MONDAY NIGHT. ANOTHER STRONG COLD FRONT WILL
SWEEP THROUGH ON TUESDAY...THEN STRONG NORTHWEST TO NORTH WINDS
WILL FOLLOW TUESDAY NIGHT THROUGH WEDNESDAY NIGHT.

DECISION SUPPORT...

DSS CODE...BLUE
DEPLOYED...NONE
ACTIVATION...NONE
ACTIVITIES...SLURRY SUPPORT
             OIL WELL BLOWOUT 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  25  55  36  70 /   0   0   0  10
BTR  29  59  41  73 /   0   0   0  10
ASD  27  56  35  69 /   0   0   0  10
MSY  34  54  44  71 /   0   0   0  10
GPT  32  55  37  67 /   0   0   0  10
PQL  28  55  34  68 /  10   0   0  10

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...FREEZE WARNING UNTIL 8 AM SUNDAY FOR THE FOLLOWING ZONES:
     ASCENSION...ASSUMPTION...EAST BATON ROUGE...EAST
     FELICIANA...IBERVILLE...LIVINGSTON...NORTHERN
     TANGIPAHOA...ORLEANS...POINTE COUPEE...SOUTHERN
     TANGIPAHOA...ST. CHARLES...ST. HELENA...ST. JAMES...ST.
     JOHN THE BAPTIST...ST. TAMMANY...UPPER JEFFERSON...UPPER
     LAFOURCHE...UPPER PLAQUEMINES...UPPER ST. BERNARD...UPPER
     TERREBONNE...WASHINGTON...WEST BATON ROUGE...AND WEST
     FELICIANA.

MS...FREEZE WARNING UNTIL 8 AM SUNDAY FOR THE FOLLOWING ZONES:
     AMITE...HANCOCK...HARRISON...JACKSON...PEARL
     RIVER...PIKE...WALTHALL...AND WILKINSON.

GM...SMALL CRAFT ADVISORY UNTIL 6 AM SUNDAY FOR THE FOLLOWING ZONES:
     BRETON SOUND...CHANDELEUR SOUND...COASTAL WATERS FROM
     BOOTHVILLE LA TO THE SOUTHWEST PASS OF THE MISSISSIPPI
     RIVER OUT 20 NM...COASTAL WATERS FROM PASCAGOULA MS TO
     STAKE ISLAND LA OUT 20 NM...COASTAL WATERS FROM PORT
     FOURCHON TO LOWER ATCHAFALAYA RIVER FROM 20 TO 60
     NM...COASTAL WATERS FROM PORT FOURCHON TO LOWER ATCHAFALAYA
     RIVER OUT 20 NM...COASTAL WATERS FROM THE SOUTHWEST PASS OF
     THE MISSISSIPPI RIVER TO PORT FOURCHON OUT 20 NM...LAKE
     BORGNE...AND MISSISSIPPI SOUND.

     SMALL CRAFT ADVISORY UNTIL 8 AM SUNDAY FOR THE FOLLOWING ZONES:
     COASTAL WATERS FROM PASCAGOULA MS TO STAKE ISLAND LA FROM
     20 TO 60 NM...COASTAL WATERS FROM STAKE ISLAND LA TO THE
     SOUTHWEST PASS OF THE MISSISSIPPI RIVER FROM 20 TO 60
     NM...AND COASTAL WATERS FROM THE SOUTHWEST PASS OF THE
     MISSISSIPPI RIVER TO PORT FOURCHON FROM 20 TO 60 NM.

&&

$$

AVIATION...95/DM
SOUNDING...GP
REST OF DISCUSSION...22/TD