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000
FXUS64 KLIX 131000
AFDLIX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
400 AM CST FRI DEC 13 2013

.SHORT TERM...
RADIATIONAL COOLING WITH SOME DRAINAGE INFLUENCES UNDERWAY THIS
MORNING. SOME HIGH CLOUDS INVADING STEADILY FROM THE WEST WITH
MUCH DEEPER CLOUD COVER OVER SOUTHEAST TEXAS IN SOUTHERN BRANCH
JET FLOW. THIS WILL BE THE TREND TODAY OF INCREASING CLOUDINESS
AND GENERAL WARMING AS WINDS VEER TO ONSHORE FLOW THROUGHOUT THE
DAY. LOW LEVEL BERNOULLI LOW DEVELOPING IN THE HIGH PLAINS WELL
EAST OF UPPER LOW CURRENTLY MOVING THROUGH ARIZONA PER WATER VAPOR
IMAGERY POSITIONING. AS CYCLOGENESIS CONTINUES TODAY...WARM
FRONTOGENESIS SHOULD COMMENCE ACROSS THE NORTH GULF IN BAROCLINIC
ZONE THAT EVENTUALLY WEDGES INTO THE FORECAST AREA TONIGHT.
TODAY`S WARMING TREND MAY BE AFFECTED BY CLOUD COVER. A DEGREE OR
TWO WAS SHAVED OFF GUIDANCE MAX TEMPS TODAY IN DEFERENCE TO
THICKENING CLOUD COVER AND COOLER WATER TEMPERATURES NEAR SHORE.
THEREAFTER...NOT MUCH CHANGE TO THE FORECAST THINKING IN THAT THE
BULK OF THE RAINFALL SHOULD ONSET TONIGHT AND MOSTLY IMPACT THE
OVERNIGHT AND EARLY SATURDAY TIME FRAME. OTHER CONCERN WILL BE HOW
MUCH ADVECTIVE FOG CAN FORM AS DEWPOINTS INCREASE THROUGH AREAL
WATER TEMPERATURES NOCTURNALLY. IT WOULD SEEM OUTSIDE RAIN
AREAS...FOG MAY BECOME BRIEFLY DENSE BUT THEN BECOME DISPERSED BY
ENSUING RAINFALL AND TEMPERATURE DIFFERENTIAL TOWARDS DAYBREAK
SATURDAY. DID MAINTAIN LOW ENDED POPS WITH MENTION OF MOSTLY LIGHT
STRATIFORM RAINFALL SATURDAY EVENING IN POST-FRONTAL COOLER AIR
THAT STILL IS AHEAD OF UPPER TROUGH. THE TROUGH AXIS DOES NOT
FULLY MOVE THROUGH UNTIL SUNDAY AFTERNOON. 24/RR

.LONG TERM...
SURFACE HIGH PRESSURE BUILDS INTO THE AREA SUNDAY...REMAINS
POSITIONED OVER THE GULF SOUTH THROUGH WEDNESDAY UNDER NORTHWEST
FLOW ALOFT THAT EVENTUALLY BECOMES ZONAL MIDDLE OF THE WEEK.
GENERAL COOLER THAN NORMAL AND DRY CONDITIONS EXPECTED THROUGH
WEDNESDAY. A CUT-OFF LOW IN THE PACIFIC OCEAN IS INDICATED TO
BECOME PICKED UP BY SOUTHERN BRANCH FLOW AND EJECTS QUICKLY
DOWNRANGE TO INDUCE CYCLOGENESIS IN THE SOUTHERN PLAINS LATE NEXT
WEEK. THIS FEATURES MOVES JUST AHEAD OF A STRONG ARCTIC INTRUSION
WITH MODEL INDICATED 1050 MB HIGH BUILDING FROM CANADA. LOCAL
IMPACTS SHOULD BE A WARM RAIN ON DEEP SOUTHERLY FETCH AHEAD OF
SYSTEM HEADING INTO NEXT WEEKEND FOLLOWED BY SHARP COOLING. 24/RR

&&

.AVIATION...
SOME HIGH CIRRUS WILL CONTINUE TO SPREAD INTO THE AREA THROUGH THE
MORNING HOURS...AND VFR CONDITIONS WILL BE THE RULE AT ALL AREA
TERMINALS.  BETWEEN 15Z AND 18Z...WINDS WILL VEER FROM THE NORTHEAST
TO A MORE SOUTHEAST DIRECTION. THESE ONSHORE WINDS WILL ADVECT
SURFACE BASED MOISTURE FROM THE GULF OF MEXICO BACK INTO THE AREA.
AS A RESULT...A SCATTERED TO BROKEN STRATUS DECK SHOULD DEVELOP OVER
THE TERMINALS BETWEEN 18Z AND 00Z.  THE STRATUS WILL FIRST DEVELOP
AT KHUM...KMSY...KNEW...AND KGPT BEFORE MOVING INLAND. CEILINGS WILL
RANGE FROM 2000 TO 3000 FEET...RESULTING IN MVFR RESTRICTIONS AT THE
TERMINALS THROUGH AROUND 03Z TO 06Z.  AFTER 06Z...A BAND OF
CONVECTION WILL MOVE INTO THE AREA.  THIS CONVECTION COULD PRODUCE
BRIEF PERIODS OF IFR CEILINGS AND VISIBILITIES...ALONG WITH GUSTY
WINDS.  32


&&

.MARINE...
A FAST MOVING LOW PRESSURE SYSTEM AND ASSOCIATED COLD FRONT WILL
IMPACT THE COASTAL WATERS THROUGH THE WEEKEND AND INTO THE EARLY
PART OF NEXT WEEK.  INITIALLY...WINDS WILL VEER FROM THE NORTHEAST
TO THE SOUTHEAST BY THIS AFTERNOON AS THE SURFACE LOW MOVES INTO
TEXAS.  AS THE LOW APPROACHES TONIGHT...AN INCREASING PRESSURE
GRADIENT WILL DEVELOP ACROSS THE AREA.  THIS WILL ALLOW WINDS TO
RISE BACK INTO EXERCISE CAUTION RANGE TONIGHT.  WINDS WILL CONTINUE
TO VEER THROUGH THE NIGHT...AND WILL TAKE ON A SOUTHWEST COMPONENT
BY TOMORROW MORNING.  AS THE COLD FRONT SWEEPS THROUGH LATE SATURDAY
IN THE WAKE OF THE PASSING LOW...WINDS WILL FURTHER SHIFT TO A
NORTHWEST DIRECTION.  A STRONG 1030 MB SURFACE HIGH WILL BEGIN TO
MOVE IN FROM THE SOUTHERN PLAINS.  STRONG COLD AIR ADVECTION OVER
THE WARMER WATERS WILL ALLOW INCREASED BOUNDARY LAYER WINDS OF 20 TO
25 KNOTS TO EASILY MIX DOWN TO THE SURFACE SATURDAY NIGHT INTO
SUNDAY.  SMALL CRAFT ADVISORY FLAGS WILL LIKELY BE NEEDED FOR THE
GULF COASTAL WATERS DURING THIS TIME FRAME DUE TO THE STRONG WINDS
AND ROUGH SEAS OF UP TO 7 FEET.  CONDITIONS WILL GRADUALLY IMPROVE
AS THE HIGH BUILDS OVER THE GULF SOUTH LATE SUNDAY INTO SUNDAY
NIGHT...WITH NORTHERLY WINDS OF 15 TO 20 KNOTS EXPECTED OVER THE
OFFSHORE WATERS INTO MONDAY MORNING.  THE GRADIENT FLOW WILL FINALLY
RELAX ENOUGH TO PUSH WINDS DOWN TO AROUND 10 KNOTS BY MONDAY
AFTERNOON.  THESE LIGHT NORTHEAST AND EASTERLY WINDS WILL PERSIST
INTO TUESDAY...AND SEAS WILL CORRESPONDINGLY DECREASE TO AROUND 1 TO
2 FEET BY TUESDAY AFTERNOON. 32

&&

.DECISION SUPPORT...
DSS CODE...BLUE.
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  59  55  67  37 /  10 100  60  20
BTR  61  57  68  39 /  10  90  60  20
ASD  64  58  73  48 /  10  70  70  20
MSY  65  60  73  48 /  10  60  70  30
GPT  61  61  73  50 /  10  50  70  30
PQL  61  60  74  46 /  10  40  70  30

&&

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

$$

24/RR
32