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

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS64 KLIX 281332
AFDLIX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
732 AM CST SUN DEC 28 2014

...SOUNDING DISCUSSION...

DRIER AIR HAS BEEN MIXING INTO THE LOWER PART OF THE ATMOSPHERE OVER
THE LAST 12 HOURS DROPPING THE PRECIPITABLE WATER FROM 2.03 INCHES
LAST EVENING TO 1.29 INCHES THIS MORNING. THE LOWEST LEVELS THOUGH
ARE STILL SATURATED YIELDING FOG AT THE LAUNCH SITE REDUCING
VISIBILITY. TEMPERATURES HAVE INCREASED BY ABOUT 1.5 DEGREES
CELSIUS IN THE LOWEST 5000 FEET COMPARED TO YESTERDAY AT THIS TIME.
OTHERWISE...TEMPERATURE CHANGE FROM 24 HOURS AGO IS SMALL. AS FOR
INSTABILITY...LIFTED INDEX WAS CALCULATED TO BE -2.0 WHILE SURFACE
BASED CAPE WAS AT ALMOST 1000 J/KG SO THUNDER WILL ACCOMPANY SOME
OF THE RAIN TODAY. WE ARE NOT EXPECTING ANYTHING SEVERE AS WIND
SHEAR IS LIMITED. WINDS WERE PRIMARILY FROM THE WEST FROM THE
SURFACE TO ABOUT 1000 FEET AND THEN MAINLY FROM THE SOUTHWEST IN
THE REMAINDER OF THE SAMPLED ATMOSPHERE. A PEAK WIND SPEED OF 94
KNOTS WAS LOCATED AT 43400 FEET.

12Z BALLOON INFO: GPS WAS NOT DETECTED AFTER THE FIRST BALLOON WAS
LAUNCHED SO ANOTHER BALLOON WAS LAUNCHED ABOUT A THIRD OF THE WAY
THROUGH THE LAUNCH WINDOW. THE SECOND BALLOON WAS SUCCESSFUL AND
REACHED A HEIGHT OF 20.2 MILES ABOVE THE GROUND BURSTING OVER DE
SOTO NATIONAL FORECAST 69 MILES DOWNRANGE FROM THE OFFICE. THE
FLIGHT LASTED 90 MINUTES.

ANSORGE

&&

.PREV DISCUSSION... /ISSUED 353 AM CST SUN DEC 28 2014/

SHORT TERM...

FRONTAL BOUNDARY SLOWLY APPROACHING THE BATON ROUGE TO MCCOMB
AREAS. LOOKS LIKE MOST OF THE HEAVIEST RAIN WILL BE WELL OFF TO
THE NORTH AND EAST OF OUR AREA. POST FRONTAL PRECIP WILL BRING MORE
SHOWERS AND ISOLATED THUNDERSTORMS THROUGHOUT THE DAY SUNDAY AS A
SOUTHWESTERLY FLOW WILL CONTINUE ALOFT. EXPECT ANY THUNDERSTORMS
THAT DEVELOP TO BE ELEVATED WITH FORCING BEING PRIMARILY FROM OVER
RUNNING ACTIVITY. RAINFALL EXPECTED TO BE AN INCH OR LESS WITH
LOCALLY HIGHER AMOUNTS THROUGHOUT THE DAY TODAY. SHOWER ACTIVITY
WILL FINALLY DIMINISH SUNDAY NIGHT/MONDAY MORNING WITH OVERCAST
STRATUS DECK TO REMAIN IN PLACE THROUGH AS LATE AS MONDAY
AFTERNOON AND EVENING.

LONG TERM...

TUESDAY THROUGH SATURDAY...CLEARING SKIES WITH DRY AND COOL
CONDITIONS TAKING HOLD ON TUESDAY. THOSE CONDITIONS ARE EXPECTED
TO REMAIN THROUGH THURSDAY. NEXT CHANCE OF RAIN FRIDAY THROUGH
SATURDAY AS THE DEVELOPMENT OF AN UPPER LEVEL LOW OVER THE CENTRAL
PLAINS LIFTS NORTHEASTWARD WITH THE POTENTIAL OF A SURFACE LOW
DEVELOPING ALONG THE NORTHERN GULF. INITIALLY AN OPEN LOW OVER
THE PLAINS BUT CLOSING OFF AND RAPIDLY DEEPENING AS THE SYSTEM
MOVES EASTWARD. BOTH THE EURO AND THE GFS ARE SHOWING A RELATIVELY
SIMILAR SCENARIO. WITH A MODERATE RETURN FLOW TAKING HOLD.
UNCERTAINTY STILL REMAINS ON TIMING...SPEED AND INTENSITY OF THE
UPCOMING SYSTEM.

AVIATION...

EVEN THOUGH THERE HAVE BEEN SOME TEMPORARY IMPROVEMENTS IN
CEILINGS...EXPECT IFR TO LIFR CEILINGS TO BE THE RULE  FOR MUCH OR
ALL OF THE FORECAST PERIOD. VISIBILITIES DO IMPROVE SOMEWHAT BEHIND
THE FRONT...WHICH IS IN THE VICINITY OF KBTR. GUIDANCE WOULD
INDICATE THAT THERE WILL NOT BE A LOT OF IMPROVEMENT IN CEILINGS
PRIOR TO MIDDAY ON MONDAY. 35

MARINE...

COASTAL SURFACE OBSERVATIONS CONTINUE TO INDICATE DENSE FOG IS A
PROBLEM. WILL LEAVE MARINE FOG ADVISORY IN PLACE THROUGH 15Z...AND
MAY NEED TO EXTEND IT LATER THIS MORNING. WILL DROP THE EXERCISE
CAUTION OVER THE OUTER WATERS WHERE WINDS HAVE DROPPED BELOW 15
KNOTS.

COLD FRONT WILL SLOWLY MOVE ACROSS THE COASTAL WATERS OVER THE NEXT
48 HOURS. COLD ADVECTION IS RATHER WEAK UNTIL TUESDAY...WHEN
EXERCISE CAUTION HEADLINES MAY BE NECESSARY. NORTHEAST WINDS LIKELY
TO STAY IN THE 15 TO 20 KNOT RANGE FOR MUCH OF TUESDAY AND
WEDNESDAY. ONSHORE WINDS BEGIN TO INCREASE FRIDAY AHEAD OF THE NEXT
SOUTHERN STREAM STORM SYSTEM...WHICH WILL MOVE THROUGH THE AREA NEXT
SATURDAY.  35

DECISION SUPPORT...

DSS CODE...BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT
             FLOOD WATCH

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  59  45  57  42 /  80  60  10  10
BTR  60  46  60  44 /  80  60  10  10
ASD  67  49  61  44 /  50  50  10  10
MSY  68  52  60  49 /  60  50  10  10
GPT  70  51  63  47 /  50  50  10   0
PQL  71  50  63  45 /  50  50  10   0

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...FLOOD WATCH UNTIL 6 PM SUNDAY FOR THE FOLLOWING ZONES:
     ASCENSION...ASSUMPTION...EAST BATON ROUGE...EAST
     FELICIANA...IBERVILLE...LIVINGSTON...NORTHERN
     TANGIPAHOA...POINTE COUPEE...SOUTHERN TANGIPAHOA...ST.
     HELENA...ST. JAMES...ST. JOHN THE BAPTIST...ST.
     TAMMANY...WASHINGTON...WEST BATON ROUGE...AND WEST
     FELICIANA.

GM...DENSE FOG ADVISORY UNTIL 9 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 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...LAKE PONTCHARTRAIN AND LAKE
     MAUREPAS...AND MISSISSIPPI SOUND.

MS...FLOOD WATCH UNTIL 6 PM SUNDAY FOR THE FOLLOWING ZONES:
     AMITE...PEARL RIVER...PIKE...WALTHALL...AND WILKINSON.

GM...DENSE FOG ADVISORY UNTIL 9 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 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...LAKE PONTCHARTRAIN AND LAKE
     MAUREPAS...AND MISSISSIPPI SOUND.

&&

$$






USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.