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000
FXUS64 KLIX 100143
AFDLIX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
743 PM CST TUE FEB 9 2010
.UPDATE...
...SOUNDING DISCUSSION...
NO PROBLEMS WITH THE FLIGHT THIS EVENING. A VERY DRY SOUNDING THIS
EVENING WITH A PW OF ONLY 0.22 INCHES. A STRONG NORTHERLY FLOW IN
THE LOWER LEVELS WILL CONTINUE TO BRING COOL TEMPERATURES INTO THE
REGION. A STEEP INVERSION IN PLACE BETWEEN 900 AND 825 MILLIBARS.
A STRONG 159 KNOT WESTERLY JET AT AROUND 240 MILLIBARS TONIGHT.
&&
.PREV DISCUSSION... /ISSUED 516 PM CST TUE FEB 9 2010/
..WINTER STORM POSSIBLE THURSDAY NIGHT INTO FRIDAY...
SHORT TERM...VERY COMPLICATED AND INTERESTING FCST FOR THE FIRST 72
HRS. FIRST 36 TO 48HRS ARE NOT TOO ROUGH BUT COME THU AND MORE SO
THU AFTN THINGS WILL BEGIN TO CHANGE AND COULD CHANGE QUICKLY.
CURRENTLY WE HAVE ONE UPPER LOW MOVING INTO IL AND THE FOCUS OF OUR
ATTENTION IS THE LOW HUGGING THE CNTRL CA COAST.
TONIGHT THROUGH WED NIGHT...HIGH PRESSURE WILL MOVE IN TONIGHT AND
DOMINATE THE AREA THROUGH EARLY THU MORNING. SKIES WILL CONTINUE TO
REMAIN MOSTLY CLEAR THROUGH TONIGHT AND INTO TOMORROW BUT HIGH
CLOUDS SHOULD START TO RETURN TOMORROW AFTN. BIGGEST CONCERN
TONIGHT IS A LIGHT TO MODERATE FREEZE ACROSS THE NRN HALF OF THE
CWA. LOWS SHOULD REMAIN ABOVE FREEZING ALONG THE SOUTHSHORE. HIGHS
TOMORROW WILL CONTINUE TO BE WELL BELOW NORMAL. H925 TEMPS OF 0 TO
2 C SUGGEST HIGHS ONCE AGAIN IN THE UPPER 40S TO LOWER 50S. AS WE
HEAD INTO THE OVERNIGHT HRS THE CA DISTURBANCE WILL HAVE MOVED
EAST AND SHOULD BE ENTERING WRN TX BY EARLY THU MORNING. CLOUDS
WILL START TO INCREASE AND THIS WILL KEEP TEMPS FROM DROPPING TOO
MUCH BUT LOWS NEAR 30 TO MID 30S WILL BE LIKELY EVERYWHERE.
THU THROUGH FRI...THIS IS GOING TO BE THE PERIOD OF CONCERN AS
CONFIDENCE CONTINUES TO INCREASE IN A WINTER STORM OCCURRING FOR
PORTIONS OF OUR CWA. INITIALLY THINGS WILL START OFF QUIET THU
MORNING BUT AS WE MOVE TWRDS MIDDAY AND THE AFTN HRS THINGS WILL
BEGIN TO PICK UP. FIRST OFF WE WILL BE LEANING HIGHLY TWRDS THE
ECMWF. THIS HAS SUPPORT FROM THE CANADIAN AND UKMET. ALSO THE TRACK
FROM THE NAM AND SREF AGREE WITH IT BUT THERE ARE TIMING ISSUES. AT
THIS TIME IT APPEARS THAT THE GFS IS A DRY AND SOUTH OUTLIER. SO
WITH THAT HERE WE GO. THE CA DISTURBANCE WILL CONTINUE TO PUSH EAST
THROUGH TX AND INTO THE LOWER MS VALLEY BY FRI MORNING. IT WILL ALSO
START TO OPEN UP BUT WILL STILL BE RATHER POTENT. AT THE SAME TIME
CYCLOGENESIS WILL BEGIN IN THE NWRN GULF WITH THE SFC LOW TRACKING
ACROSS THE NRN GULF JUST SOUTH OF THE LA COAST THU NIGHT. THE TRACK
OF THE SFC LOW IS VERY FAVORABLE FOR WINTER WEATHER FOR PORTIONS OF
THE LOWER MS VALLEY. ALSO FAVORABLE IS THAT COLD DRY AIR WILL
ALREADY BE IN PLACE. THE DRY AIR IS ACTUALLY SOMEWHAT BENEFICIAL.
WE WILL MOISTEN THE COLUMN FROM TOP DOWN AND AS THIS OCCURS WE
WILL COOL THE COLUMN BY EVAPORATION WHICH WILL CONTINUE TO
INCREASE THE CHANCE FOR WINTER WEATHER FOR AREA ALONG AND NORTH OF
THE I 10/12 CORRIDOR. PRECIP WILL BEGIN TO COME TO AN END MIDDAY
FRI AS LL WINDS START TO FINALLY BACK AROUND TO THE WNW AND THEN
NW HELPING TO DRY THE AREA OUT.
THIS IS THE TRICKY PART. WITH THIS SFC LOW TRACK THIS IS GOING TO
PUT SRN MS AND ACROSS THE BORDER INTO LA IN A FAVORABLE LOCATION FOR
MODERATE TO HEAVY SNOW. A FRONTOGENETIC BAND WILL START TO DEVELOP
AND MOVE NE ACROSS SRN LA BEFORE STALLING SOMEWHERE OVER IN SRN MS
OR THE LA/MS BORDER. AT THE SAME TIME WE WILL SEE STRONG H7 WAA AND
BOTH OF THESE FEATURES ARE GOING TO PROMOTE STRONG LIFT. IN ADDITION
THE MID LVL ACCENT WILL INCREASE WITH THE APPROACH OF THE STRONG
DISTURBANCE. IT IS WHERE THIS BAND DEVELOPS THAT IS OF A BIG
CONCERN. RIGHT NOW WITH IT DEVELOPING AND POSSIBLY STALLING ACROSS
OUR NRN 3RD WE CAN EXPECT TO SEE MODERATE TO HEAVY SNOW FOR AT LEAST
A 6 HR PERIOD(POSSIBLY LONGER). AS THE SFC LOW PUSHES A LITTLE
FURTHER TO THE EAST THIS WILL BECOME MORE OF A DEFORMATION ZONE
CONTINUING TO LEAD TO MODERATE AND HEAVY SNOW. INITIALLY LIGHT RAIN
MIXED WITH SLEET MAY BEGIN ACROSS WRN PORTIONS OF THE CWA MIDDAY THU
BUT BY LATE AFTN EARLY EVEN I EXPECT LIGHT RAIN TO HAVE EXPANDED
ACROSS THE ENTIRE CWA WITH SLEET POSSIBLE ACROSS SERN LA ALONG AND
NORTH OF I 10. NORTH OF A LINE FROM BATON ROUGE TO BOGALUSA THINGS
COULD BEGIN TO QUICKLY CHANGE OVER TO SNOW DURING THE EVN WITH
MODERATE TO HEAVY SNOW BEGINNING TO FALL IN THESE AREAS LATE IN THE
EVN AND ESPECIALLY AFTER MIDNIGHT. PRECIP WILL LIKELY REMAIN LIQUID
SOUTH OF THE 10/12 CORRIDOR BUT I WOULD NOT BE COMPLETELY SURPRISED
TO SEE SOME SLEET ALONG THE SOUTHSHORE. OVERALL SNOWFALL
ACCUMULATIONS OF 2-4 INCHES WITH ISOLATED HIGHER AMOUNTS LOOK
POSSIBLE FOR SOUTHERN MS AND THE NRN FLORIDA PARISHES. FURTHER SOUTH
TWRDS THE 10/12 CORRIDOR WE COULD SEE ACCUMULATIONS ANYWHERE FROM A
FEW TENTHS TO 3 INCHES.
AGAIN THE BIG CONCERN IS GOING TO BE WHERE THIS FRONTOGENETIC BAND
DEVELOPS AND A LOT BASICALLY DEPENDS ON THE TRACK OF THE SFC LOW. IF
THE SFC LOW IS SLIGHTLY FURTHER SOUTH THAN CURRENTLY FCST THEN WE
WILL LIKELY REMAIN MOSTLY LIQUID. THIS IS BECAUSE THE HEAVY BAND OF
PRECIP WOULD LIKELY DEVELOP FURTHER SOUTH TWRDS THE COAST AND IT
WILL JUST BE TOO WARM. A FURTHER NORTH SFC LOW TRACK WILL CAUSE THE
BAND OF DEVELOP FURTHER NORTH AGAIN KEEPING MOST OF THE CWA IN
LIQUID. RIGHT NOW THIS TRACK IS ALMOST IDEAL FOR THE NRN 3RD TO GET
A PRETTY GOOD WINTER STORM...HOPEFULLY THE MDLS WILL COME INTO EVEN
MORE AGREEMENT AS THE CA SYSTEM GETS FURTHER INTO THE UPPER AIR
NETWORK.
LONG TERM...NOT GOING TO FOCUS TOO MUCH ON THE EXTENDED AS LUCKILY
IT REMAIN MOSTLY QUITE. WE WILL SEE ANOTHER FRONT COME THROUGH LATE
SUN AND THIS COULD BRING SOME LIGHT SHRA TO THE AREA SUN EVN AND
EARLY MON. AS FOR LUNDI GRAS/PRESIDENTS DAY AND MARDI GRAS...WE
SHOULD REMAIN MOSTLY DRY BUT TEMPS WILL CONTINUE TO BE WELL BELOW
NORMAL WITH LOWS IN THE MOSTLY IN THE MID 30S TO LOWER 40S AND HIGHS
IN THE MID 50S. /CAB/
AVIATION...CLOUD COVER HAS BEEN RAPIDLY DISSIPATING ACROSS THE
AREA. ALL STATIONS SHOULD BE VFR BY SUNSET. STRONG NORTHWESTERLY
WINDS WILL FINALLY WEAKEN AS WELL AS WE MOVE INTO THE EVENING AN
OVERNIGHT HOURS. HOWEVER...MSY WILL STILL REMAIN ELEVATED AT NEAR 10
KNOTS. NO SIGNIFICANT CHANGES EXPECTED TOMORROW. WINDS WILL BE
AROUND 10 KNOTS OUT OF THE NORTH. A CIRRUS DECK IS PROGGED TO
DEVELOP IN THE MORNING HOURS AND INCREASE IN COVERAGE THROUGHOUT THE
DAY. VFR WILL PREVAIL THROUGH THE PERIOD AT ALL TERMINALS.
MARINE...
COLD FRONT PUSHED THROUGH THIS MORNING WITH WINDS QUICKLY PICKING UP
OUT OF THE NW THIS MORNING AND REMAINING HIGH THROUGH THE DAY. WINDS
WILL LIKELY PICK UP FURTHER TONIGHT AS H925 WINDS APPROACH 35-40KTS.
THESE SHOULD MIX DOWN TO THE SFC BRINGING WIND GUSTS NEAR GALE
FORCE.. SEAS WILL REMAIN HIGH...POSSIBLY UP TO 10 FT IN THE OUTER
WATERS. SMALL CRAFT ADV ARE IN EFFECT FOR ALL OF THE COASTAL WATERS
AND TIDAL LAKES THROUGH TOMORROW MORNING. WINDS SHOULD START TO EASE
TOMORROW MORNING ESPECIALLY OVER THE LAKES. THERE WILL BE ABOUT A 24
HR RESPITE BEFORE PICKING BACK UP THU AS ANOTHER GULF LOW BEGINS TO
DEVELOP OVER THE NWRN GULF. ADV`S WILL LIKELY BE NEEDED FOR THIS
SYSTEM AS WELL THROUGH FRI. /CAB/
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 27 47 29 45 / 0 0 10 30
BTR 29 48 32 45 / 0 10 10 60
ASD 27 50 31 49 / 0 10 10 30
MSY 33 48 35 48 / 0 10 10 40
GPT 29 50 31 50 / 0 10 10 20
PQL 30 51 28 48 / 0 10 10 20
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 6 AM WEDNESDAY 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...COASTAL WATERS FROM
THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER TO LOWER
ATCHAFALAYA RIVER LA OUT 20 NM...AND LAKE PONTCHARTRAIN AND
LAKE MAUREPAS.
MS...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 6 AM WEDNESDAY 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...COASTAL WATERS FROM
THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER TO LOWER
ATCHAFALAYA RIVER LA OUT 20 NM...AND LAKE PONTCHARTRAIN AND
LAKE MAUREPAS.
&&
$$
