National Weather Service Weather Forecast Office

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

000
FXUS64 KLIX 091457
AFDLIX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
957 AM CDT SUN MAR 9 2014

.UPDATE...

RECENT SATELLITE AND RADAR TRENDS HAVE PROMPTED AN UPDATE FOR THE
FORECAST TODAY. HAVE REMOVED POPS OVER AREAS NORTH OF THE I-10
CORRIDOR AND HAVE RAISED POPS FOR THE LOUISIANA COAST AND AREAS
OFFSHORE INTO THE LIKELY RANGE. HAVE ALSO ADJUSTED SKY COVER TODAY
TO REFLECT THE MORE SCATTERED NATURE OF THE CLOUD COVER THIS
MORNING. A WEAK FRONTAL BOUNDARY IS CURRENTLY DRAPED ALONG THE
LOUISIANA COAST AND SHOULD SLOWLY PUSH OFFSHORE THROUGH THE DAY.
NO OTHER CHANGES TO THE ONGOING FORECAST WERE MADE. 32

&&

.PREV DISCUSSION... /ISSUED 837 AM CDT SUN MAR 9 2014/

SOUNDING DISCUSSION...

ISSUES WITH ELEVATION DRIVE CONTROLLER FOR THIS MORNINGS
FLIGHT...BUT STILL ABLE TO GET A FULL SOUNDING. FLIGHT TERMINATED
ABOUT 15 MILES NORTH OF BILOXI AT 106.5K FEET. MOISTURE HAS
CHANGED LITTLE SINCE LAST NIGHT WITH PRECIPITABLE WATER VALUE OF
0.80 INCH THIS MORNING. SOUNDING IS COOLER THAN 24 HOURS AGO. ANY
CONVECTION TODAY WILL BE ELEVATED WITH BASES ABOVE 850 MB. JET MAX
AT 44K FEET AT 108 KNOTS.

PREV DISCUSSION... /ISSUED 342 AM CDT SUN MAR 9 2014/

SHORT TERM...IT HAS BEEN QUIET BUT THE ATMOSPHERE IS TRYING TO
MOISTEN UP. RADAR HAS BEEN SHOWING RETURNS ALL NIGHT BUT EITHER VERY
LGT SPRINKLES OR NONE IS REACHING THE GROUND AS OF 8Z.

THE BEST CHANCE FOR ANY MEASURABLE RAIN IS NOW AND THROUGH 15Z.
AFTER THAT THIS WEAK IMPULSE WILL PULL OFF TO THE EAST WITH RISING
HGHT THIS AFTN AND OVERNIGHT TONIGHT. IN ADDITION THE WEAK COLD
FRONT IS TRYING TO SLIDE SOUTH THROUGH THE LOWER MS VALLEY WHICH IS
PROVIDING A LITTLE LL CONVERGENCE BUT THIS FRONT WILL WASH OUT TODAY
WITH HIGH PRESSURE QUICKLY BUILDING BACK OVER THE GULF SOUTH.

THE DISTURBANCE MOVING SOUTH THROUGH THE DESERT SW WILL CONTINUE TO
DRIFT SOUTH AND DEEPEN (CLOSING OFF) OVER OLD MEXICO AND THE BAJA
TODAY AND TONIGHT. THROUGH THE DAY TOMORROW IT WILL BEGIN TO GET
KICKED OUT TO THE EAST AS THE NEXT PAC NW DISTURBANCE DIVES SE. BY
00Z TUE THE CLOSED LOW WILL PUSH INTO SRN TX AND THEN OVER THE NWRN
GULF EARLY TUE AND OVER THE N-CNTRL GULF COAST BY TUE EVNG. AS THIS
OCCURS WEAK LOW PRESSURE AT THE SFC WILL DEVELOP OVER THE GULF (MUCH
STRONGER SFC LOW WILL DEVELOP WITH THE PAC NW DISTURBANCE OVER THE
CNTRL PLAINS TUE). ALL OF THIS WILL LEAD TO INCREASING MOISTURE AND
ABUNDANT LIFT TUE. IN FACT THERE MAY BE ENHANCED DIVERGENCE OVER
SELA AS WE WILL MOVE UNDER BOTH THE RRQ OF ONE JET STREAK AND THE
LFQ OF ANOTHER. WITH THIS WE WILL HAVE 60-80% POPS ACROSS ALL OF
COASTAL LA AND OVER THE IMMEDIATE MS COAST.

AS FOR THUNDER BOTH THE GFS AND ECMWF ARE IN GOOD AGREEMENT WITH A
SRLY TRACK THUS KEEPING THE REGION IN THE COOL SECTOR FOR THE MOST
PART. THAT SAID THERE WILL STILL BE SOME ELEVATED INSTABILITY AND
AMPLE FORCING TO GET ISLTD TSRA. HEAVY RAIN MAY BECOME A LITTLE BIT
OF A PROBLEM THANKS TO THE ENHANCED DIVERGENCE COMBINING WITH PWS
THAT WILL BE AROUND 1.75.

LONG TERM...THE MEDIUM RANGE MDLS ARE IN RATHER DECENT AGREEMENT
THROUGH 12Z SAT BEFORE STARTING TO DIVERGE SOME HEADING INTO THE
LATER PART OF THE WEEKEND. OVERALL THE EXTENDED FCST LOOKS COOLER
AND DRIER AFTER WED AND WILL USE A BLEND OF THE MDLS TO GET THE BEST
LOOKING FCST.

OUR TUE SYSTEM WILL CONTINUE TO MOVE EAST PUSHING INTO FL AND
OPENING UP WITH THE L/W TROUGH FINALLY PUSHING THROUGH THE MID
AND LOWER MS VALLEY AND OVER THE OH/TN VALLEYS. THE COLD FRONT WILL
MOVE THROUGH THE CWA EARLY WED WITH THE COLDER AND DRIER AIR
BEGINNING TO POUR INTO THE AREA LATE WED MORNING/MIDDAY. THE MAY BE
SOME LINGERING SHRA WED BUT WE SHOULD START TO DRY OUT LATE IN THE
DAY.

WED NIGHT THROUGH FRI WILL BE MUCH QUIETER WITH WELL BELOW NORMAL
TEMPS AND NO RAIN. WE WILL MOVE UNDER NW FLOW WED NIGHT BUT QUICKLY
BACK UNDER ZONAL FLOW AS THE NEXT DISTURBANCE MOVES ACROSS THE
PLAINS AND TWRDS THE LOWER MS VALLEY. AT THE SFC HIGH PRESSURE WILL
QUICKLY BUILD IN WED NIGHT AND SLIDE ACROSS THE SERN CONUS THROUGH
THE REMAINDER OF THE WORK WEEK. BY LATE FRI AND FRI NIGHT THAT
DISTURBANCE THAT SHOULD ALREADY BE MOVING INTO THE LOWER MS VALLEY
COULD BRING A RETURN OF LIGHT SHRA TO THE AREA FRI NIGHT AND INTO
SAT.

HEADING INTO THE WEEKEND THE MDLS BEGIN TO DIVERGE WITH RESPECT TO
THE STRENGTH AND TIMING OF THE NEXT SYSTEM. BOTH THE GFS AND ECMWF
DO DEVELOP A STRONG DISTURBANCE LATE NEXT WEEKEND/EARLY NEXT WEEK
BUT HOW DEEP/DISPLACED TO THE SOUTH IS THE MAIN QUESTION. EITHER WAY
IT DOES LOOK LIKE UNSETTLED WEATHER SUN AND MON. /CAB/

MARINE...
ONGOING DOCILE CONDITIONS ARE EXPECTED TO PERSIST OVER THE COASTAL
WATERS FOR THE NEXT COUPLE DAYS AS THE AREA GENERALLY REMAINS UNDER
HIGH PRESSURE. THIS RIDGE WILL SLIDE EAST ON TUESDAY AS A SURFACE
LOW DEVELOPS AND TRACKS ACROSS THE NORTHERN GULF OF MEXICO. 15 TO 20
KNOT SOUTHEAST WINDS WILL LIKELY DEVELOP TUESDAY AFTERNOON AS THE
NOW APPROACHES AND THEN TRANSITION TO SOUTHWEST TUESDAY NIGHT AS IT
PASSES. A STRONG COLD FRONT WILL THEN SWING THROUGH WEDNESDAY...
LENDING TO SMALL CRAFT ADVISORY CONDITIONS. GALE FORCE GUSTS WILL
CERTAINLY BE POSSIBLE DURING THE OVERNIGHT PERIOD. WINDS WILL RELAX
ON THURSDAY AS SURFACE HIGH QUICKLY MOVES IN. EAST TO SOUTHEAST FLOW
WILL THEN PERSIST THE REST OF THE WEEK AND INTO THE WEEKEND AS THE
RIDGE MOVES EAST.

MEFFER

AVIATION...
A STRATUS DECK AT AROUND 4000 FEET IS LINGERING OVER THE SOUTHERN AND
WESTERN PORTIONS OF THE FORECAST AREA THIS MORNING.  THIS CLOUD DECK
SHOULD EVENTUALLY SPREAD BACK ACROSS THE ENTIRE REGION AS AN
ELEVATED INVERSION STRENGTHENS.  OVERALL...VFR CONDITIONS WILL BE
FOUND AT ALL OF THE TERMINALS THROUGH THIS EVENING.  HOWEVER...THE
INVERSION MAY BECOME SURFACE BASED AT KMCB RESULTING IN A PERIOD OF
REDUCED VISIBILITIES.  HAVE INCLUDED A TEMPO GROUP OF IFR
VISIBILITIES AROUND DAYBREAK. RADAR DOES INDICATE LIGHT SHOWER
MOVING ACROSS THE AREA. HOWEVER...OBSERVATIONS SAY OTHERWISE. IT
APPEARS THAT A DRY LATER IS EVAPORATING MOST OF THE DROPLETS BEFORE
THEY HIT THE GROUND. NOT EXPECTING MUCH IMPACT FROM RAIN TODAY.

MEFFER

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  72  52  74  56 /  10  10  10  20
BTR  73  54  74  55 /  10  10  10  30
ASD  72  54  74  56 /  10  10  10  20
MSY  70  55  72  58 /  20  10  10  30
GPT  70  55  72  58 /  10  10  10  20
PQL  72  51  72  54 /  10  10  10  20

&&

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

$$