FXUS64 KLIX 100531
AFDLIX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
1131 PM CST WED DEC 9 2009
.AVIATION...
WITH COLD FRONT NOW WELL PAST THE AREA AND HIGH PRESSURE BUILDING
IN...EXPECT NORTHERLY WINDS TO PERSIST. SPEEDS WILL REMAIN FAIRLY
LIGHT OVERNIGHT AND PICK UP A COUPLE HOURS AFTER SUNRISE AS WELL
AS BECOME NNE TO NE. MID LEVEL CLOUD DECK WILL DISSIPATE THURS BUT
HIGH CLOUDS SHOULD PERSIST. VFR WILL PREVAIL THRU THE PERIOD.
&&
.PREV DISCUSSION... /ISSUED 405 PM CST WED DEC 9 2009/
..ANOTHER BOUT OF RAIN EXPECTED...
SHORT TERM...MUCH QUIETER DAY TODAY AND TOMORROW SHOULD FOLLOW
SUIT. COLD FRONT HAS ALREADY PUSHED THROUGH THE COASTAL WATERS AND
WAS BASICALLY STRETCHING NE FROM THE CNTRL GULF ACROSS THE FL
PANHANDLE AND THEN INTO THE CAROLINA'S. ANOTHER AREA OF LOW PRESSURE
IS IN THE BAY OF CAMPECHE AND THIS ARE OF LOW PRESSURE WILL BE THE
CULPRIT LATE THIS WEEK AND INTO THE WEEKEND.
WELL TONIGHT THROUGH TOMORROW NIGHT WILL BE FAIRLY QUIET. HIGH
PRESSURE WILL CONTINUE TO PUSH IN FROM THE NORTHWEST BUT DO TO
MOSTLY ZONAL FLOW IT WON'T GET TO FAR SOUTH SO MOST OF THE REAL GOOD
COLD AIR WILL REMAIN JUST OFF TO OUR NORTH. THAT SAID WE WILL STILL
SEE SOME CHILLY AIR ACROSS THE REGION. OVERALL WE WILL BE A GOOD BIT
COOLER THAN LAST NIGHT BUT THE EXTREME NRN/NWRN ZONES WILL PROBABLY
SEE TEMPS DROP TO NEAR 30...EVEN ISOLATED UPPER 20S WILL BE
POSSIBLE. MAV GUI SEEMS TO BE A TAD TO HIGH SO I WILL GO CLOSER TO
THE ENSEMBLE MEAN AND MET FOR LOWS TONIGHT ESPECIALLY ACROSS THE NRN
HALF OF THE CWA. TOMORROW HIGH CLOUDS WILL LIKELY START TO FILTER
BACK IN OVER THE AREA. COMBINE THIS WITH COOL LL TEMPS(H935 AROUND
4-5C) AND WE SHOULD REMAIN IN THE LOWER TO MID 50S. AS WE HEAD INTO
THU NIGHT THE SFC HIGH WILL BEGIN TO PUSH OFF TO OUR EAST WHILE THE
AREA OF LOW PRESSURE IN THE BAY OF CAMPECHE WILL SLOWLY START TO
WORK TO THE NORTH. ISENTROPIC LIFT WILL START TO SLOWLY INCREASE
DURING THE EARLY MORNING HRS AND THIS COULD BRING SOME LIGHT SHRA TO
THE COASTAL PARISHES WEST OF THE MS RIVER.
FRI AND SAT ...THIS WILL BE THE IMPACT PORTION OF THE FCST. WE COULD
SEE ANOTHER BOUT OF MODERATE TO EVEN HEAVY RAIN AT TIMES BEGINNING
LATE FRI AND POSSIBLY PERSISTING THROUGH SAT. WE WILL BE IN WSWRLY
FLOW WITH NUMEROUS WEAK IMPULSES EXPECTED TO TRAVERSE ACROSS THE
REGION. ALSO OUR AREA OF LOW PRESSURE WILL CONTINUE TO SLOWLY WORK
NNE INTO THE NWRN GULF BY LATE SAT MORNING WHILE HIGH PRESSURE WILL
PUSH INTO THE DELMARVA REGION. THIS IS GOING TO KEEP US IN A
MODERATE SERLY LL FLOW WHICH WILL HELP TO PUMP VERY RICH GULF
MOISTURE INTO THE REGION(H85 THETA E AIR OF 330-333K). THE WSW FLOW
ALOFT WILL PUMP IN PAC MOISTURE AT THE SAME TIME AND THE COMBINATION
OF THESE TWO WILL LEAD TO DEEP MOISTURE WITH PWS APPROACHING
1.5-1.75" WHICH IS ANYWHERE FROM 175-205% OF NORMAL. THE AREA OF LOW
PRESSURE IS EXPECTED TO SLOWLY MOVE FROM THE NWRN GULF TWRDS OUR
COASTAL PARISHES WITH A WEAK INVERTED TROUGH DRAPED ACROSS THE
REGION. THIS WILL ACT AS A FOCUS FOR RAIN AND AS WEAK IMPULSES MOVE
THROUGH ALOFT WE SHOULD SEE NUMEROUS TO WIDESPREAD SHRA AND EMBEDDED
TSRA AT TIMES BEGINNING FRI NIGHT AND PERSISTING THROUGH MUCH OF
SAT. THERE WON'T BE A GREAT DEAL OF INSTABILITY TO WORK WITH BUT
ENOUGH ELEVATED INSTABILITY WILL LEAD TO A FEW TSRA. THE COMBINATION
OF LIFT AND AMOUNT OF MOISTURE EXPECTED IN PLACE COULD LEAD TO RAIN
BEING QUITE EFFICIENT. BECAUSE OF THE RECENT RAINS WE HAD WE CAN'T
TAKE TOO MUCH MORE IN SOME AREAS AND DUE TO THAT WE HAVE ISSUED AN
ESF TO HIGHLIGHT THE POSSIBILITY OF MODERATE TO HEAVY RAIN WHICH
COULD LEAD TO LOCALIZED FLOODING ISSUES.
THE WEAK SFC LOW WILL START TO PUSH NE INTO THE LAND AREAS LATE SAT
NIGHT BEFORE FINALLY FILLING IN SOMEWHERE ACROSS THE SERN CONUS LATE
SUN. THIS SHOULD LEAD TO ACTIVITY SLOWING DOWN SOME AND MAYBE A
BRIEF DRY PERIOD. THAT SAID IF WE HAVE A DRY SPELL IT WILL BE SHORT
LIVED AS OUR NEXT FRONT/SYSTEM IS EXPECTED LATE MON. /CAB/
LONG TERM...MEDIUM RANGE MDLS ARE HAVING SOME DIFFICULTY WITH NEXT
WEEK BUT MOST AGREE WITH ANOTHER SYSTEM COMING THROUGH LATE MON AND
INTO TUES. WITH THAT I HAVE MADE ONLY MINOR ADJUSTMENTS TO THE GRIDS
IN THE EXTENDED.
MON THROUGH TUE...SRLY WINDS WILL BRING MOISTURE BACK INTO THE REGION
AND AS A DISTURBANCE DROPS INTO THE SRN/CNTRL PLAINS AND A COLD
FRONT MOVES THROUGH THE CWA WIDESPREAD SHRA AND TSRA WILL BE
POSSIBLE ONCE AGAIN. THERE LOOKS LIKE THERE WILL BE A GREAT DEAL
MORE FORCING TO WORK WITH...WITH THIS SYSTEM AND ONCE AGAIN WE COULD
HAVE TO DEAL WITH MODERATE TO HEAVY RAIN.
HOPEFULLY BY WED WE WILL MOVE INTO A DRIER PATTERN AND THIS WILL
HOPEFULLY LET THE AREA FINALLY DRY OUT BUT WITH THE EL NINO PATTERN
IN PLACE WE WILL LIKELY REMAIN ACTIVE FOR MUCH OF THE MONTH.
ONE THING TO MENTION MSY IS ALREADY AT 8.04" OF RAIN MAKING THIS
ALREADY THE TENTH WETTEST DECEMBER ON RECORD. WITH RAIN EXPECTED
AGAIN LATE THIS WEEK AND EARLY NEXT WEEK WE WILL ONLY MOVE UP AND
THE WETTEST DECEMBER IS JUST OVER 10" SO WE COULD BE IN THE TOP 3 IF
NOT THE WETTEST BY THE END OF THE WEEKEND.
/CAB/
AVIATION...VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD.
NORTHWEST WINDS WILL PERSIST THROUGH THE PERIOD WITH GUSTIER
CONDITIONS AT MSY AND GPT. 95/DM
MARINE...NO BIG CHANGES IN THE FCST. WE STILL HAVE A SCY IN PLACE
EVEN THOUGH WINDS AREN'T QUITE THERE YET I DO SEE WINDS PICKING UP
TONIGHT AS CAA HELPS MIX DOWN SOME STRONGER WINDS. WINDS WILL LIKELY
SAY UP THROUGH FRI AS WEAK LOW PRESSURE IN THE NWRN GULF AND HIGH
PRESSURE ACROSS THE SERN CONUS KEEPS THE PRESSURE GRADIENT TIGHT
OVER THE AREA. THE BIG DIFFERENCE IS WINDS WILL VEER AROUND FROM THE
N TO THE E AND THEN SE BY FRI AFTN. /CAB/
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 30 51 34 47 / 0 0 10 40
BTR 34 54 37 49 / 0 0 10 60
MSY 43 54 42 54 / 0 0 10 60
GPT 39 53 37 51 / 0 10 10 40
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 6 AM FRIDAY FOR THE FOLLOWING ZONES:
COASTAL WATERS FROM PASCAGOULA MS TO THE SOUTHWEST PASS OF
THE MISSISSIPPI RIVER FROM 20 TO 60 NM...COASTAL WATERS
FROM PASCAGOULA MS TO THE SOUTHWEST PASS OF THE MISSISSIPPI
RIVER OUT 20 NM...COASTAL WATERS FROM THE SOUTHWEST PASS OF
THE MISSISSIPPI RIVER TO LOWER ATCHAFALAYA RIVER LA FROM 20
TO 60 NM...AND COASTAL WATERS FROM THE SOUTHWEST PASS OF
THE MISSISSIPPI RIVER TO LOWER ATCHAFALAYA RIVER LA OUT 20
NM.
MS...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 6 AM FRIDAY FOR THE FOLLOWING ZONES:
COASTAL WATERS FROM PASCAGOULA MS TO THE SOUTHWEST PASS OF
THE MISSISSIPPI RIVER FROM 20 TO 60 NM...COASTAL WATERS
FROM PASCAGOULA MS TO THE SOUTHWEST PASS OF THE MISSISSIPPI
RIVER OUT 20 NM...COASTAL WATERS FROM THE SOUTHWEST PASS OF
THE MISSISSIPPI RIVER TO LOWER ATCHAFALAYA RIVER LA FROM 20
TO 60 NM...AND COASTAL WATERS FROM THE SOUTHWEST PASS OF
THE MISSISSIPPI RIVER TO LOWER ATCHAFALAYA RIVER LA OUT 20
NM.
&&
$$
