FXUS64 KLIX 281007
AFDLIX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
407 AM CST SAT NOV 28 2009
.SHORT TERM...
SURFACE RIDGE IS CURRENTLY LOCATED DIRECTLY OVER THE AREA...HENCE
THE CALM WINDS OVER THE ENTIRE CWA. THIS HIGH WILL SHIFT EASTWARD
DURING THE DAY WHICH WILL BRING SOUTHERLY FLOW BACK TO THE AREA.
DEWPOINT RISES WILL ENSUE FROM THIS ONSHORE FLOW AND TEMPERATURES
WILL BEGIN TO MODIFY TODAY. HIGHS WILL BE NEAR NORMAL IN WITH MID
60S AREAWIDE. DIDN/T STRAY FAR FROM GUIDANCE WITH ONLY A FEW TWEAKS
TO TRY TO ACCOUNT FOR LATEST TRENDS.
WATER VAPOR IMAGERY SHOWS UPPER LOW SPINNING ACROSS CA AND FLATTER
NORTHERN BRANCH TROUGH IN CANADA NORTH OF MONTANA. THE LOW WILL DIG
SEWD TOWARDS MEXICO WHILE THE NORTHERN SWINGS ACROSS THE UPPER MS
VALLEY. THIS TROUGH WILL BE MUCH MORE PROGRESSIVE THAN THE LOW WHICH
WILL CAUSE IT TO BE CUT OFF AND SLOWLY SAG SEWD.
.LONG TERM...
A COLD FRONT WILL APPROACH THE CWA LATE SUNDAY NIGHT AS TROUGH MOVES
ACROSS THE EASTERN HALF OF THE CONUS. A SLOWER PROGRESSION SUGGESTED
BY MODELS PROMPTED TO REMOVAL OF POPS FROM FORECAST FOR SUNDAY AFTN.
THIS TROUGH WILL BE MOVING RATHER QUICKLY ACROSS THE COUNTRY WHICH
WILL RESULT IN THE COLD FRONT STALLING ALONG THE NORTHERN GULF
MONDAY. HAVE INCREASED POPS TO LIKELY CATEGORY FOR MOST OF THE FA
MONDAY AFTERNOON AS THIS BOUNDARY SITS ON TOP OF THE AREA.
ANOTHER NORTHERN TROUGH WILL MOVE OUT OF CANADA WHICH SHOULD PICK UP
THE CUT OFF LOW AND SHIFT IT BACK NEWD ACROSS CENTRAL TEXAS TOWARDS
THE OHIO RIVER VALLEY. MODELS SUGGEST CYCLOGENESIS IN THE
NORTHWESTERN GULF MONDAY NIGHT. THIS SURFACE LOW WILL TRACK NEWD
TOWARDS THE GULF COAST. THERE/S STILL SOME CONTINUITY DIFFERENCES ON
THE EXACT TRACK WITH GFS HAVING A MORE SOUTHERLY TRACK KEEPING IT
COMPLETELY OFF THE LA COAST WHILE ECMWF TAKES THE LOW ACROSS SERN
LA. BASED ON EITHER OF THESE TRACKS...MOST STRONG STORMS WILL REMAIN
OFFSHORE IN THE WARM SECTOR.
THE COLD FRONT ASSOCIATED WITH THIS SYSTEM WILL SWING THRU WED WITH
THE POSSIBILITY OF SOME RESIDUAL SHOWERS WRAPPING AROUND THE UPPER
LOW WHICH WOULD INFRINGE UPON NORTHERN PORTIONS OF THE CWA. POPS
FORECAST HAVE BEEN ADJUSTED TO ACCOUNT FOR THIS.
MOST OF THE COUNTRY WILL THEN BE UNDER LONG WAVE TROUGH BY LATE THIS
WEEK. TEMPS WILL BE ABOUT 10 DEGREES BELOW NORMAL. EXPECTING HIGHS
FROM MID 50S TO 60 AND LOWS IN THE 30S WITH ANOTHER CHANCE FOR
FREEZING TEMPS IN SOUTHERN MS.
MEFFER
&&
.AVIATION...
RATHER STRONG UPPER LEVEL DISTURBANCE BRINGING THICK CIRRUS CLOUD
COVER MAINLY AT OR ABOVE 25KFT. AIRMASS REMAINS VERY DRY BELOW 25KFT
BUT HEAVY VIRGA SHOULD MOISTEN COLUMN TO LOWER DECKS TO 10KFT LATER
THIS MORNING AND AROUND 6KFT THIS AFTERNOON. OTHERWISE...VFR
CONDITIONS TO PREVAIL WITH CEILINGS REMAINING WELL ABOVE 3KFT AND
VSBYS TO STAY ABOVE 6SM AT ALL TERMINALS THROUGH 18Z SUNDAY. 24/RR
&&
.MARINE...
LIGHT WINDS AND LOW SEAS ARE EXPECTED THROUGH EARLY MONDAY BEFORE
BUILDING WITH APPROACHING STRONG COLD FRONT. TIMING OF FRONTAL
PASSAGE THROUGH COASTAL WATERS STILL APPEARS TO BE MONDAY LATE
AFTERNOON OR EVENING HOURS. MODELS CONTINUE TO INDICATE A
SIGNIFICANT LOW PRESSURE SYSTEM DEVELOPING IN THE WEST GULF ALONG
THE FRONT MONDAY NIGHT THAT MOVES NORTHEAST INTO THE FLORIDA
PANHANDLE WEDNESDAY MORNING. THIS COULD POTENTIALLY BECOME A GALE
SYSTEM FOR A BRIEF TIME DEPENDING ON HOW DEEP THE LOW ACTUALLY
BECOMES WHILE MOVING NEAR THE MOUTH OF THE MS RIVER. THE LOOP
CURRENT IS UNUSUALLY COOLER THAN NORMAL BASED ON LATEST AOML SST
ANALYSIS...WHICH SHOULD LIMIT DEGREE OF BAROCLINIC ENHANCEMENT.
NONETHELESS...FREQUENT GALE GUSTS AND SEAS TO 10 FEET SEEM PLAUSIBLE
FOR TUESDAY NIGHT PARTICULARLY IN THE OUTER COASTAL WATERS. TIDES
WILL ALSO HAVE TO BE MONITORED BUT STRONG OFFSHORE FLOW MAY OFFSET
ANY SURGE RUNUP TO NEGATE OR MINIMIZE FLOODING CONCERNS. 24/RR
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 65 45 72 54 / 0 10 10 40
BTR 67 49 73 57 / 0 10 10 40
MSY 66 52 73 60 / 0 10 10 20
GPT 65 46 72 57 / 0 0 10 20
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
