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New Orleans Local Weather thread - dkmac - 12-21-2008 06:59 AM

000
fxus64 klix 210929
afdlix

area forecast discussion
national weather service new orleans la
329 am cst sun dec 21 2008

.short term...
Strong cold front moving se at 30 mph this morning and will move
out of the region by mid morning. The tail end of the front will
settle near south texas and a sfc low will begin to form as
baroclincity increases over the west gulf. This low will quickly
move ne along another front moving into the area wed.

Problem areas in the fcast will revolve around this transition
from a cold dry air mass to a quickly warming moistening one. As
moisture flows northward with the sfc low late monday...some light
rain will begin to form over the most western peripheral portion
of the area. Ceilings will be around 8k` and should become deep
enough by 2am tue morning to produce some light rain at that
level. Meantime the sfc temp will be in the mid 30s over extreme
southern miss. This is not the issue...but the dp temp is. Dp
temps will be running in the teens as rain starts falling through
the mid levels at 45-50 degrees f. As the rain falls into the dry
air near the sfc virga will occur along with a moistening and
warming of these lower levels.

Since the light rain falls through air around 50 degrees before
falling into the colder air it will cause a vertical warm and
moisture advection process. This will cause wet bulb cooling
throughout the boundary layer and may even cause the temp to fall
to freezing at the top of the bl. This process is so quick to
modify the dry cool air that a very small window of an ice pellet
mixing with rain will be possible. Placement and timing of this
will be between 3am and 5am tuesday morning over extreme southern
miss and some areas along the la border. Hazardous driving
conditions or any other problems are not going to accompany this
event.


.long term...
As the sfc low moves out...the cold front will stall over la by
wed night as another stronger front moves across the foothills of
the rockies. The front moves back to the nw in the form of a strongly
inverted trough. This will be a slow process for a few days
starting thu. Now for the wet stuff. Several short wave
disturbance will rush through the upper and mid level sw flow.
Since the old front has moved north...the area will be left with
plenty of deep moisture. This will help showers and a few
thunderstorms break out starting thu night and lasting through
fri night. Placement will be the variable to nail down over the
next few days but currently this looks to be from se la through
northern ala. Then the next strong cold front moves in to force
all the mess out by next weekend. It looks to be a relatively warm
and possibly wet christmas day.

&&

.aviation...
/12z taf issuance/
strong cold front moved through kmcb at 0737z and kbtr around 0840z.
Current progress is measured at ese 30kt and should move through
kasd around 1030z...kmsy around 1135z and kgpt around 1145z. A 25nm
wide band of broken -shra precedes the frontal passage with very
little indicated after windshift. Upstream conditions show a narrow
band of mvfr ceilings just before clearing to vfr high ceilings and
no visibility restrictions generally north and west of kaex-ktvr
line. This is indicated in tafs mainly after 14z. 24

&&

.marine...
Cold front expected to move off the coast after 12z from west to
east and should be south and east of the mississippi coastal waters
before 18z. Strong northwest winds expected to onset shortly after
frontal passage and continue through tonight with cold air advection
before leveling off some monday afternoon. Small craft advisory
winds and seas with occasional gale force gusts today into this
evening. Baroclinic return expected tuesday with strong onshore flow
to maintain high seas and small craft advisory conditions tuesday
and tuesday evening before moderating wednesday through friday. Next
cold front to affect the north gulf waters expected late saturday
night to early sunday morning. 24


New Orleans Local Weather thread - dkmac - 12-22-2008 08:38 AM

000
fxus64 klix 220915
afdlix

area forecast discussion
national weather service new orleans la
315 am cst mon dec 22 2008

.short term...

An extremely dry airmass...with dewpoints in the lower teens and
single digits will overspread the region today. Low relative
humidities and persistent northerly winds around 10 mph will allow
for high fire danger across the region. However...winds will not
be strong enough to support a red flag warning. Going into
tonight...the airmass will be a marked change...as surface ridging
centered over the lower mississippi valley slides toward the
southeastern states. Surface flow will turn more easterly by this
evening...and then southeasterly overnight. This southeasterly
flow will allow for quick moisture return overnight in the low
levels. The upper levels will remain moist through the period...as
strong westerly...and then southwesterly flow from 850mb on upward
continues. This strong southwesterly flow will bring mid to high
level cloudiness to the region through tonight. Going into
tuesday...low level southeasterly flow will increase...as the
pressure gradient between the ridge to the east...and a developing
area of low pressure in the plains increases. This strong
southerly flow will allow pw values to rise to around 1.5 inches
by tuesday afternoon. With enough low level moisture in
place...and a series of weak vort maxes slipping through on the
southwest flow...scattered showers should develop tuesday
afternoon. These hit and miss showers will persist through
thursday. Model soundings show that enough mid-level instability
will be in place to support a few elevated thunderstorms wednesday
into wednesday night. Temperatures will also warm dramatically on
tuesday...with strong warm air advection expected tuesday night
into wednesday. In fact...it appears that temperatures will hold
steady...and possibly rise throughout tuesday night. Readings will
be well above normal by wednesday.

.long term...

Christmas day looks to warm and muggy with continued scattered
showers. However...overall coverage will be lower...as a weak area
of negative vorticity slips through aloft. Stronger positive
vorticity advection will take hold thursday night into friday as
another area of low pressure takes shape in the plains. This
trough looks much stronger than the expected to pass north of the
region tuesday into wednesday. As a result...a fairly strong cold
front should impact the forecast area on saturday. Strong dynamic
forcing combined with ample low level instability will support the
development of thunderstorms in advance of the front. Model
soundings at this time...show a low cape and high shear
environment. Overall shear profiles are unidirectional...but
strong speed shear will be in place. In addition...some drier air
should be in place around 500mb. This profile is supportive of
some bowing segments and isolated wind damage events. The
situation will have to be monitored through the week...as the
system evolves. The front should stall over the coastal waters
sunday...and remain in place through sunday night. North of the
front...a much cooler and drier airmass will advect in.
Temperatures will fall back to normal for this time of year.
However...skies will never completely clear due to the front being
in the vicinity and southwesterly flow continuing aloft. This
drier airmass will remain in place through monday.

&&

.aviation...
/12z taf issuance/
cavok conditions for next 24 hours. Low level winds should weaken to
lower levels mainly after 18z today but current low level winds
indicated northeast 25-30 kt on vad wind profiles through 3kft. 24

&&

.marine...
Strong offshore flow to persist today as cold air advection
continues into the north gulf waters through tonight. Winds are
expected to decrease to moderate levels late tuesday morning with
seas responding slowly tuesday afternoon. As high pressure moves
east...a well developed easterly swell train will likely result
along with strong baroclinic return onshore flow by wednesday. Small
craft advisories may need to be posted for the strong return flow
tuesday night. 24

&&

.fire weather...
Nocturnal relative humidity levels are in the 35 to 50 percent range
at 2 am...a really rare condition for the gulf south. Dewpoints in
the teens are over much of the area with single digit dewpoint
readings upstream...indicative of very low relative humidity
expectations today. Northerly winds will be softening
today...thereby coming short on red flag warning criteria. Will
issue a fire danger statement to address very dry air in place for
today. Conditions should improve tuesday as onshore flow returns and
humidity levels approach normal levels once again. 24


New Orleans Local Weather thread - ROLLTIDE - 12-22-2008 05:19 PM

FXUS64 KLIX 222131
AFDLIX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
331 PM CST MON DEC 22 2008

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER WESTERN TENNESSEE THIS AFTERNOON. LOW
PRESSURE DEVELOPING OVER THE ROCKIES. ISENTROPIC LIFT ON THE 295K
AND 300K SURFACES HAS AIDED IN THE DEVELOPMENT OF LIGHT
PRECIPITATION ECHOES. DUE TO THE VERY DRY AIR AND LOW WET BULB
TEMPERATURES...THE PRECIPITATION HAS GENERALLY IN THE FORM OF
VERY LIGHT SLEET. MID LEVEL CLOUD COVER ACROSS MUCH OF THE AREA.
TEMPERATURES RANGE FROM UPPER 30S NEAR MCCOMB TO MIDDLE 40S
ELSEWHERE. DEW POINTS GENERALLY IN THE TEENS...BUT RANGE FROM 8 AT
MCCOMB TO 30 AT BOOTHVILLE.
&&

.SHORT TERM...
ISENTROPIC LIFT SHOULD GRADUALLY REFOCUS TO THE NORTH AND WEST OF
THE AREA TONIGHT. WHILE A FEW SPRINKLES OR VERY LIGHT SLEET MAY
OCCUR OVER THE NEXT FEW HOURS...NO MEASURABLE PRECIPITATION IS
EXPECTED. WARM AIR ADVECTION KICKS IN OVERNIGHT. ABUNDANT CLOUD
COVER WILL AID IN HOLDING TEMPERATURES UP UNTIL THE WARM ADVECTION
KICKS IN...SO OVERNIGHT TEMPERATURES WILL NOT CRATER OUT AS
CURRENT DEW POINTS WOULD INDICATE. AFTER TEMPERATURES DROP OFF
SEVERAL DEGREES DURING THE EVENING...THEY SHOULD BECOME STEADY OR
RISE THE REMAINDER OF THE NIGHT.

WARM ADVECTION TO CONTINUE THROUGH WEDNESDAY...WITH CHANCES FOR
PRECIPITATION EACH PERIOD. NO REAL FOCUS FOR THE PRECIPITATION
UNTIL THE NEXT COLD FRONT MOVES INTO THE AREA ON WEDNESDAY. THIS
FRONT WILL NOT MOVE THROUGH THE ENTIRE AREA...BUT WILL WASH OUT
SOMEWHERE IN THE REGION. TEMPERATURES WILL MODERATE TO NEAR NORMAL
TOMORROW...AND AGAIN WILL SEE LITTLE IF ANY OVERNIGHT TEMPERATURE
FALL TOMORROW NIGHT. TEMPERATURES ON WEDNESDAY EXPECTED TO BE AT
LEAST 10 DEGREES ABOVE NORMAL...AND THAT MIGHT BE UNDERCUTTING
SLIGHTLY. 35
&&

.LONG TERM...
UPPER FLOW REMAINS SOUTHWESTERLY FOR THURSDAY THROUGH AT LEAST
SUNDAY. ONE STRONG IMPULSE MOVES THROUGH THE MISSISSIPPI RIVER
VALLEY SATURDAY...WITH A FINAL ONE PUSHING THROUGH ABOUT SUNDAY
NIGHT OR MONDAY. INSTABILITY WILL BE SUFFICIENT FOR CONVECTION
FRIDAY AND SATURDAY...WITH SPEED SHEAR EVIDENT IN THE FORECAST
SOUNDINGS. THIS WOULD LEAVE THE DOOR OPEN FOR STRONG
CONVECTION...PROBABLY CENTERED ON SATURDAY. WILL MENTION IN THE
HWO...BUT TOO EARLY TO KEY ON IN OTHER PRODUCTS.

BOTTOM LINE ON EXTENDED FORECAST IS THAT THERE WILL BE A MENTION
OF PRECIPITATION PRETTY MUCH EVERY DAY...WITH THE BEST CHANCE
LIKELY TO BE SATURDAY AFTERNOON. TEMPERATURES ARE EXPECTED TO BE
ABOVE NORMAL FOR MOST OR ALL OF THE EXTENDED FORECAST PERIOD. THAT
SHOULD ENSURE THAT THE MONTHLY AVERAGE TEMPERATURE FOR DECEMBER ENDS
UP SEVERAL DEGREES ABOVE NORMAL. 35
&&


New Orleans Local Weather thread - dkmac - 12-23-2008 06:54 AM

000
fxus64 klix 230944
afdlix

area forecast discussion
national weather service new orleans la
344 am cst tue dec 23 2008

.short term...

Strong warm air and moisture advection is taking shape across the
cwa...as a gulf flow begins to form off the south texas coast
early this morning. This low should track northeastward through
the western gulf and into louisiana today into tonight. Expect
deep southerly flow in advance of this low to continue to pump
moisture and warmer air into the area throughout the day and into
tonight. In fact...it appears that temperatures tonight should
remain steady or rise a bit through the night. Expect showers to
overspread the area by this afternoon...as dry air in the low
levels quickly moistens up. These showers should continue into
tonight.

Going into tomorrow...a frontal boundary will approach the
cwa...as a strong upper level shortwave sweeps through the plains
states into the great lakes. In advance of the front...expect some
convection...as a fairly warm and moist airmass will be in place.
Have went with likely pops for northern and western zones...and
high chance pops elsewhere. Model soundings indicate that the
best instability will remain elevated...and that overall dynamics
are supportive of some stronger thunderstorms...especially for
northern zones in southwest mississippi. However...surface based
convection will be tough to attain. The front should stall over
the region wednesday night...as the shortwave driving the front
southeastward...lifts into the northeast. Southwesterly flow
parallel to the front will impede forward progress. The front
should then quickly lift to the north on thursday...as another
strong upper level trough digs into the rockies...and a surface
low takes shape in the central plains. Expect low end chance pops
wednesday night into thursday. Temperatures should be a bit cooler
on thursday as the front lingers over the region...but overall
readings will remain above normal.

.long term...

Going into friday...deep southerly flow will continue off the
gulf...with above normal temperatures and muggy conditions
continuing. A broad area of lift associated with a strong pva in
advance of the upper level trough deepening in the plains will
allow for continued cloud cover and scattered showers.
Overall...friday should have a fairly tropical feel to it. Surface
based instability will also increase friday into friday
night...which will play a role going into the weekend.

By saturday...the upper level trough in the plains will begin to
pull eastward. The system should take on a fairly neutral tilt as
it progresses eastward...which will be a bit more supportive of
stronger convective development. This overall upper level pattern
is supported by both the gfs and ecmwf. However...the models have
some timing issues...with the ecmwf picking up on further
deepening of the system for saturday. This will slow the progress
down a bit...and there is a good 12 hour lag between both models.
Due to the overall uncertainty on the speed of the system...have
went with a blend of the models for the weekend time frame. Keep
in high end chance pops for saturday...and then linger chance pops
through saturday night for all zones. A frontal boundary should
pull into the cwa in the saturday afternoon time frame...and then
slowly sweep through into sunday night. Overall instability will
be highly supportive of convection...with cape running around 1000
j/kg. Dynamic support will also be in place for the development of
strong and possibly severe convection. Strong speed shear of
around 30-40 knots in the lowest 3 km will support the
development of severe thunderstorms. Current profiles suggest that
damaging winds will be the main threat.

The front should then pull offshore on sunday...and finally clear
the region by monday. Strong subsidence and dry air advection in
the wake of the front will allow for rapidly clearing skies on
monday. A return to more seasonable temperatures can be expected
as a somewhat cooler airmass settles in.

&&

.aviation...
/12z taf issuance/
warm air advection slowly returning to the area but starting with
very low dewpoints and low level dry air that will slowly saturate
as virga from above 8500 feet wet-bulbs the sounding this morning.
This will eventually allow ceilings to lower to mvfr levels later
this morning as is currently the case over east texas and spreading
eastward. The 00z sounding earlier supported isolated ice pellets at
the onset of precipitation but this threat appears to have advected
north into the i-20 corridor area of kshv...thereby indicating any
precipitation process will likely remain liquid at terminals
kmsy-kbtr-kmcb-kgpt...though kmcb may have an outside shot at 5-10
minutes duration of light sleet mixed within the rainfall at onset.
As warm air advection gets underway in earnest tonight...ceilings
should lower to ifr levels along with mvfr visibilities. 24

&&

.marine...
Moderate easterly flow and seas already around 6 feet in the coastal
waters will only increase steadily as gradient tightens between
modifying high pressure along eastern seaboard and developing
mechanical low pressure area over the west gulf of mexico. Models
indicate this feature to move north towards high island thereby
inducing steady southerly flow to assist baroclinic return gustiness
over the north gulf into tonight. Sea levels are starting at
relatively low levels but this flow pattern is conducive to enhanced
tides and this will be monitored the next couple of days. Sabine
pass in southwest louisiana was indicated to be about 1.3 feet above
normal at this time but grand isle was behaving along forecast tide
curve. Next cold front of pacific maritime origin only makes it into
coastal plains before becoming diffuse thursday...with prevailing
onshore flow expected until late saturday when next continental cold
front moves into the gulf. 24


New Orleans Local Weather thread - dkmac - 12-24-2008 06:39 AM

000
fxus64 klix 240931
afdlix

area forecast discussion
national weather service new orleans la
331 am cst wed dec 24 2008

.short term...

A broad area of ascent...combined with a very warm and unstable
airmass in the low levels will allow for continued shower
development through friday. Within this general pattern of
southerly flow in the mid to upper levels of the atmosphere...a
weak frontal boundary will pull into the region today. Overall
forcing along the front will fairly limited...but upper level
support will be in place...especially over mississippi...as the
entrance region of a 80 knot jet streak moves through. With this
enhanced upper level support in mind...have went with likely pops
for areas north of interstate 12. South of i-12...expect chance
pops through the day...with lowest chances over the coastal
waters. Have included a mention of thunder for areas north of
i-10...but overall convective activity should remain
fairly limited in nature...as some capping aloft should be in
place. These conditions will persist into the evening hours
tonight...before the jet streak pulls far enough eastward to limit
any further development. Temperatures will be near record highs
wednesday.

In addition...with the frontal boundary draped over the
cwa...overall boundary layer winds will be significantly lower
than the past few days. With these light winds...and a weak
surface inversion developing due to some minor cold air
advection...expect some fog to develop overnight. The fog may be
locally dense...but do not expect widespread dense fog for
tonight.

The front should pull back to the north on thursday...which will
allow for lower pops thursday into friday. However...the general
pattern will not change...with a broad area of lift remaining in
place in the mid and upper levels. With this in mind...cannot
rule out a few showers...as a warm and moist air advects back into
the region thursday night into friday...over a cooler pool of air
in the low levels. The strong warm air advection...will allow for
near record temperatures once again on friday.

.long term...

A much stronger frontal system will impact the area for the
weekend. All of the medium range models indicated that a very deep
upper level trough will develop in the rockies...and then eject
eastward as a neutrally tilted trough through the weekend. Overall
timing differences have been resolved...and it now appears that
the system will impact the region from saturday afternoon into
saturday night. The front will then pull offshore on sunday...but
convective potential will still exist over the coastal waters
through sunday.

The convective potential will be much higher with this
system...as warm moist unstable air in the low levels...interacts
with a neutral...or slightly negatively tilted trough. If the
trough does gain a negative tilt...upper level lift will
increase...supporting deeper convection. However...at this
time...it appears the system will remain neutral in orientation.
The potential for strong and severe thunderstorm development will
be much higher...with capes rising to around 1000 j/kg and strong
omega values supported by a jet streak sliding through the lower
mississippi valley. This jet streak will allow for strong speed
shear throughout the lowest 6km...with high helicity values in
excess of 250 m2/s2 expected. Model soundings indicate that any
convection will be surface based...and that the overall flow will
be unidirectional in nature. Expect a squall line to develop ahead
of the frontal boundary associated with a surface low passing
through the mid-south. Several bowing segment with damaging winds
and isolated tornadoes could develop along this squall line. In
addition...a few lone wolf supercells could develop ahead of the
squall line saturday afternoon into saturday evening. This
situation will have to be monitored over the next couple of days.

In the wake of the front...a strong surface based ridge of high
pressure will build in. Some weak cold air advection will take
place...allowing temperatures to fall back to normal for this
time of year. Strong dry air advection and subsidence associated
with the ridge will clear skies rapidly sunday night into monday.
This ridge and more seasonable airmass will persist through
tuesday. Going into the middle of next week...the global models
begin to differ...with some models showing another strong surge of
cold air descending into the gulf south...while others show warmer
temperatures and moisture feeding back into the area.
Overall...uncertainty increases beyond tuesday.

&&

.aviation...
/12z taf issuance/
large scale lift within gradient flow between east coast ridge and
mid-america frontal zone providing a large area of mvfr ceilings and
locally ifr ceilings this morning across la and ms. Deeper moisture
column over texas has ifr ceilings and mvfr visibilities. The
frontal zone is expected to continue eastward to near a ktvr-kiah
configuration by 25/00z. Marine layer showers should increase
steadily in coverage as well as gain vertical development later this
afternoon though lack of strong dynamics may limit coverage of
thunder. Front stalls during the day thursday over the area before
returning north as a warm front friday. 24

.marine...
Strong onshore flow this morning is producing a tidal anomaly around
1 foot above normal along the gulf coast but this should abate later
today and certainly by the next tide cylce thursday. Gradient is
expected to weaken as the frontal zone currently over the central
u.s. Approaches and settles across the gulf coastal plains late
tonight and thursday. Seas near 11 feet well offshore this morning
is expected to subside below 7 feet by early this afternoon.
Moderate onshore flow should resume friday in advance of the next
cold frontal approach that now appears to move across the coastal
waters saturday night. 24


New Orleans Local Weather thread - dkmac - 12-25-2008 08:07 AM

Dense Fog Advisory

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE NEW ORLEANS LA
340 AM CST THU DEC 25 2008

...DENSE FOG ADVISORY IS IN EFFECT UNTIL 9 AM CST...

.DENSE FOG WILL CONTINUE TO AFFECT AREAS OF SOUTHEAST LOUISIANA AND
COASTAL MISSISSIPPI...ESPECIALLY NEAR BODIES OF WATER. VISIBILITIES
WILL BE ONE QUARTER MILE OR LESS AT TIMES ACROSS THESE AREAS THROUGH
CHRISTMAS MORNING. THE DENSE FOG IS EXPECTED TO BEGIN CLEARING AROUND 9
AM...BUT LIGHT FOG COULD PERSIST THROUGH NOON.

000
FXUS64 KLIX 250936
AFDLIX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
336 AM CST THU DEC 25 2008

.SHORT TERM...

WARM AND MOIST AIRMASS COMBINED WITH LIGHT BOUNDARY LAYER WINDS
AROUND 10 KNOTS HAS ALLOWED FOR A WIDESPREAD ADVECTION FOG EVENT
TO DEVELOP TONIGHT. THESE LIGHT WINDS ARE DUE TO A STATIONARY
FRONT BEING IN THE REGION...AND WEAK MID-LEVEL RIDING POKING IN
FROM THE EAST. VISIBILITIES OF ONE QUARTER MILE OR LESS ARE QUITE
COMMON NEAR BODIES OF WATER ACROSS THE CWA. WITH THIS IN
MIND...HAVE CONTINUED THE DENSE FOG ADVISORY FOR AREAS NEAR THE
COAST AND TIDAL LAKES...AND HAVE EXTENDED THE FOG ADVISORY FOR AN
ADDITIONAL HOUR OVER BODIES OF WATER.

IN ADDITION TO THE FOG...WITH DEEP SOUTHWEST FLOW CONTINUING TO
PUMP WARM AND MOIST AIR INTO THE REGION...AND THEN RIDING UP AND
OVER THE WEAK COLD POOL BEHIND THE FRONT...EXPECT ISENTROPICALLY
INDUCED SHOWER ACTIVITY THROUGH THE DAY. HAVE KEPT IN CHANCE
POPS THROUGH THE DAY. GIVEN ATMOSPHERIC INSTABILITY PROFILES...DO
NOT EXPECT ANY THUNDERSTORM DEVELOPMENT. THE FRONTAL BOUNDARY
SHOULD BEGIN TO PULL BACK TO THE NORTH LATE TONIGHT INTO
TOMORROW...AS ANOTHER AREA OF LOW PRESSURE AND MUCH DEEPER UPPER
LEVEL TROUGH PULL INTO THE SOUTHERN PLAINS. HOWEVER...EXPECT
CONTINUED LIGHT BOUNDARY LAYER WINDS OF 10 TO 15 KNOTS...WHICH
SHOULD ALLOW FOR REDEVELOPMENT OF DENSE FOG TONIGHT. THE SOUTHERLY
FLOW WILL CONTINUE...AND THE WEAK COLD POOL OVER NORTHERN ZONES
WILL COMPLETELY DISAPPEAR BY FRIDAY MORNING. IT APPEARS THAT NEAR
RECORD HIGHS WILL BE POSSIBLE ON FRIDAY. THESE WARM AND UNSTABLE
CONDITIONS SHOULD PERSIST INTO SATURDAY. OVERALL...NO LOW LEVEL
FEATURES WILL BE IN PLACE TO FOCUS THIS INSTABILITY...BUT A BROAD
AREA OF GENERAL ASCENT ASSOCIATED WITH POSITIVE VORTICITY
ADVECTION IN ADVANCE OF THE TROUGH IN THE SOUTHERN PLAINS...WILL
ALLOW FOR ISOLATED SHOWERS FRIDAY INTO SATURDAY MORNING.

GOING INTO SATURDAY AFTERNOON AND THEN THE OVERNIGHT HOURS...A
STRONG COLD FRONT SHOULD PASS THROUGH THE REGION. THE
GFS...NAM...AND ECMWF ALL ARE IN GOOD AGREEMENT ON A NOCTURNAL
PASSAGE OF THE FRONTAL BOUNDARY. LOOKING AT MODEL
SOUNDINGS...AMPLE INSTABILITY WILL BE IN PLACE...WITH CAPES IN THE
500-1000 J/KG RANGE...AND DEEP MOISTURE THROUGHOUT THE LOW AND
MID-LEVELS. DYNAMICALLY...IT LOOKS LIKE THE LOWER MISSISSIPPI
VALLEY WILL BE POSITIONED UNDER THE RIGHT ENTRANCE REGION OF AN
100+ KNOT JET AXIS. THIS WILL ALLOW FOR STRONG LIFT ACROSS THE
REGION...AND WILL SUPPORT THE DEVELOPMENT OF STRONG CONVECTION IN
ADVANCE OF THE FRONT. THERE WILL BE ENOUGH SHEAR IN PLACE TO
SUPPORT SOME SEVERE THUNDERSTORM DEVELOPMENT...WITH 0-3 KM SHEAR
OF 30 KNOTS EXPECTED. OVERALL...THE SHEAR PROFILE WILL BE
UNIDIRECTIONAL IN NATURE...SUPPORTING THE DEVELOPMENT OF SQUALL
LINE WITH EMBEDDED BOWING SEGMENTS. WITH THIS IN MIND...THE
DEVELOPMENT OF THE SYSTEM WILL HAVE TO MONITORED AS ANY CHANGE IN
SHEAR PROFILES COULD SUPPORT OR LIMIT SEVERE CONVECTION. HAVE WENT
WITH LIKELY POPS FOR ALL ZONES SATURDAY NIGHT TO REFLECT THE
FRONTAL PASSAGE. TEMPERATURES SHOULD ALSO BEGIN TO COOL BEHIND THE
FRONT OVER NORTHERN AND WESTERN ZONES.

.LONG TERM...

GOING INTO SUNDAY...THE FRONT WILL BEGIN TO PULL INTO THE COASTAL
WATERS IN THE MORNING HOURS. HAVE KEPT IN SOME POPS FOR NORTHERN
AND WESTERN ZONES IN THE MORNING...BUT DRY THEM OUT IN THE
AFTERNOON. EXPECT SHOWERS TO PERSIST OVER SOUTHERN AND EASTERN
PORTIONS OF THE CWA THROUGH SUNDAY AFTERNOON...BEFORE DRYING OUT
IN THE EVENING. HOWEVER...OVER THE COASTAL WATERS...THE FRONT
SHOULD STALL A BIT...AS A WEAK IMPULSE RIDING THROUGH ON WESTERLY
FLOW MOVES INTO THE SOUTHERN PLAINS. THE FRONT WILL CLEAR THE
COASTAL WATERS ON MONDAY AS THIS SECONDARY IMPULSE PULLS TO THE
EAST. TEMPERATURES SHOULD DROP OR HOLD STEADY THROUGH THE DAY ON
SUNDAY IN THE WAKE OF THE FRONT. AFTER THE SECONDARY IMPULSE MOVES
THROUGH...MUCH STRONGER COLD AND DRY AIR ADVECTION WILL TAKE PLACE
WITH RAPIDLY CLEARING SKIES AND A RETURN TO MORE SEASONABLE
TEMPERATURES EXPECTED. HIGH PRESSURE WILL REMAIN PARKED OVER THE
AREA THROUGH TUESDAY. BEYOND TUESDAY...MODELS ARE GOOD AGREEMENT
THAT ANOTHER SYSTEM SHOULD IMPACT THE REGION. HOWEVER...THERE ARE
TIMING AND STRENGTH DIFFERENCES BETWEEN THE MEDIUM RANGE MODELS
WEDNESDAY THROUGH FRIDAY. AT THIS TIME...HAVE WENT WITH SLIGHT
CHANCE POPS FOR MIDWEEK TO REFLECT THIS UNCERTAINTY.

&&

.AVIATION...
VLIFR CONDITIONS IN DENSE FOG WILL CONTINUE FROM KMSY-KASD-KGPT AND
OTHER COASTAL AIRPORTS THROUGH MID MORNING IN THE WARM HUMID AIR
JUST SOUTHEAST OF THE STALLED FRONTAL BOUNDARY. THE FRONTAL BOUNDARY
WILL BE WEAKENING AND RETREATING THIS MORNING...SO CONDITIONS SHOULD
DETERIORATE TO IFR AT KBTR AND KMCB BY 11-12Z. MVFR TO VFR WEATHER
WILL RETURN BY LATE MORNING WITH MAINLY VFR WEATHER EXPECTED THIS
AFTERNOON. ISOLATED TO SCATTERED SHOWERS WITH BRIEF PERIODS OF
IFR/MVFR CONDITIONS ARE POSSIBLE THROUGH THE DAY...AND THESE WILL BE
DIFFICULT TO TIME IN THE TAFS. IFR/LIFR CATEGORY CIGS/VSBYS ARE
LIKELY TO REDEVELOP AT ALL TAF SITES THIS EVENING WITH AT LEAST
TEMPO VLIFR CONDITIONS IN DENSE FOG EXPECTED DURING THE 06Z-15Z TIME
FRAME FRIDAY. 22

&&

.MARINE...
SEA AND LAKE FOG WILL BE THE MAIN PROBLEM THIS MORNING AND PROBABLY
AGAIN TONIGHT AND FRIDAY MORNING DUE TO LIGHT TO OCCASIONALLY
MODERATE SOUTHERLY WINDS BRINGING WARM HUMID AIR BACK OVER COOL
WATER. THE LOWEST VISIBILITIES THIS MORNING WILL LIKELY BE OVER LAKE
PONTCHARTRAIN WHERE THE CAUSEWAY POLICE REPORTED 500 FEET AT 300 AM.
A STALLED FRONTAL BOUNDARY JUST NORTH AND WEST OF LAKE PONTCHARTRAIN
WILL MOVE BACK NORTH AS A WARM FRONT LATER TODAY AND TONIGHT.
MODERATE ONSHORE FLOW WILL PREVAIL FRIDAY WITH STRONGER SOUTHEAST
WINDS POSSIBLY BRINGING SMALL CRAFT ADVISORY CONDITIONS SATURDAY.
THE NEXT COLD FRONT IS EXPECTED TO MOVE ACROSS THE COASTAL WATERS
LATE SATURDAY NIGHT AND SUNDAY MORNING. AT THIS TIME IT APPEARS
THAT WINDS IN THE WAKE OF THIS FRONT WILL BE JUST BELOW SMALL CRAFT
ADVISORY CRITERIA. 22


New Orleans Local Weather thread - dkmac - 12-26-2008 07:56 AM

Dense Fog Advisory

URGENT - WEATHER MESSAGE...CORRECTED
NATIONAL WEATHER SERVICE NEW ORLEANS LA
356 AM CST FRI DEC 26 2008

...A DENSE FOG ADVISORY IS IN EFFECT FROM MIDNIGHT TONIGHT UNTIL
9 AM CST FRIDAY FOR AREAS ALONG COASTAL MISSISSIPPI AND COASTAL
LOUISIANA...INCLUDING METRO NEW ORLEANS...

.DENSE FOG WILL PERSIST OVER COASTAL LOUISIANA...INCLUDING THE NEW
ORLEANS AREA...AND COASTAL MISSISSIPPI THROUGH EARLY FRIDAY
MORNING. VISIBILITIES WILL BE ONE QUARTER MILE OR LESS AT TIMES.
THE FOG IS EXPECTED TO LIFT BY 9 AM FRIDAY.

000
fxus64 klix 260942
afdlix

area forecast discussion
national weather service new orleans la
342 am cst fri dec 26 2008

.short term...

Vad wind profiles indicate the boundary layer winds have increased
to around 20 knots early this morning. This has resulted in a bit
more mixing within the boundary layer which has allowed
visibilities to improve over inland areas away from large bodies
of water. However...over coastal areas and regions near lake
pontchartrain and maurepas...the cooler waters are keeping a
healthy fog bank in place. Have decided to cancel the fog advisory
for inland areas...and shortened the length of time for the
remaining advisory to 15z. Boundary layer winds should continue to
increase through the day and into tonight...as a the pressure
gradient tightens up in advance of deepening trough over the four
corners. This will prohibit fog formation tonight. However...a low
stratus deck is possible...and have reflected this with increasing
sky cover tonight.

Dynamically...all of the models are in fairly good agreement
through the weekend. The overall system is bit slower in these
latest solutions...mainly due to a secondary impulse expected to
pass through sunday night into monday. With this slower solution
in mind...have pushed back the highest chances of precip into
saturday night and sunday morning. It also looks like the front
will stall along the coast sunday afternoon...in response to the
secondary impulse swinging through. The front should finally clear
the coastal zones monday afternoon...as a surge of negative
vorticity advection...subsidence...and dry air advection takes
hold.

Temperatures will remain mild today and tomorrow...with
record or near record highs possible. With these warm and humid
conditions in mind...ample instability will be in place in advance
of the approaching upper level trough and associated frontal
boundary expected to pull into the region saturday night into
sunday morning. Capes of 500 to 1000 j/kg are expected...along
with lifted indices of -2 to -3. This instability will be
assisted by strong dynamic forcing to allow for convective
development ahead of the front. It looks like a 100+ knot jet
streak will orient itself over the ohio valley and mid-south. The
lower mississippi valley will be in the favorable right entrance
region of the jet streak...allowing for some deep lift and thus
deeper convection in the region. In addition...helicity values
will be quite high...mainly due to strong speed shear of 30 knots
over the lowest 3 km. Overall helicity values are expected to be in
the 150 to 250 range saturday night into sunday morning. These
shear values...combined with fairly unidirectional flow...support
the development of a squall line with embedded bowing segments.
These bowing segments could produce isolated damaging wind gusts.

As the front stalls sunday night along the coast...expect a broad
area of isentropic lift to take hold...as a shallow cold pool
invades in the low levels. This will allow for continued
showers inland...and periods of heavier rain right along the
coast...as well as overcast conditions.

.long term...

Going into monday...strong dry air advection and subsidence
associated with a surface ridge building from the northwest will
bring clearing skies and seasonable temperatures to the region. In
the early morning hours...a few showers may linger along the coast
before the front pulls into the central gulf. However... These
conditions will be short lived. Clear skies and seasonable
temperatures will persist into tuesday as the ridge axis slowly
moves through the gulf south. Overall...upper level flow will turn
more zonal across the region. This zonal flow will allow a fast
moving vort max to pass through on wednesday. In the low
levels...the ridge axis will pull to the east of the region
tuesday night...with a rapid return of gulf moisture and warmer
temperatures expected. This strong warm air advection will feed
isentropically induced showers and clouds tuesday night. On
wednesday...a weak frontal boundary will slide in from the north
and stall over the cwa...as the upper level vort max slides to the
east. With this frontal boundary in place...and continued
southwesterly flow in the mid-levels...expect a broad area of
isentropic lift to keep clouds and showers in through thursday.
Temperatures will also be warmer...readings climbing back to near
70 for new years eve and day.

&&

.aviation...
Klix vad wind profile and model data shows boundary layer and 1 kft
winds increased about 5 knots from 03z to 06z and have held ever
since. As would be expected...cigs have risen and vsbys have
improved from vlifr category vsbys/cigs to mvfr category vsbys and
lifr category cigs over the last few hours at kmsy...kbtr...kasd and
kmcb. Kgpt remains fogged in due to their closer proximity to the
cool gulf waters. Model data indicates winds will either stay the
same or perhaps increase a couple knots through 14z. Have amended
tafs for the latest improvements and will continue to amend and
hopefully get a good handle on conditions for the early to mid
morning flights. Satellite also indicates the low cloud layer is
shallower than yesterday which combined with higher winds and north
retreat of frontal boundary should help with gradual improvement
towards vfr category vsbys and mvfr category cigs 15-17z. Winds will
be even stronger tonight and saturday morning which should produce
low cigs in stratus but less vsby restrictions in fog. 22

&&

.marine...
Sea and lake fog will not persist as long as yesterday due to
stronger boundary layer winds...and visibilities should increase to
1-2 nm by late morning over near shore coastal waters and 1/2 to 1
nm over tidal lakes by late morning. Southeast winds 10 to 15 knots
today will increase to near 20 knots by midday saturday as the
pressure gradient increases between high pressure to the east and
lower pressures over the plains. Fog should be much less of an issue
tonight and saturday morning. Seas in 3 to 4 feet range today will
increase to 4 to 6 feet saturday...possibly 7 feet in some outer
waters saturday afternoon. Cold frontal passage saturday night will
be associated with slightly weaker winds near 15 knots or 10 to 15
knots as winds shift to north and northeast. 22


New Orleans Local Weather thread - ROLLTIDE - 12-27-2008 07:41 AM

NATIONAL WEATHER SERVICE MOBILE AL
347 AM CST SAT DEC 27 2008

.SHORT TERM...(TODAY THROUGH TONIGHT)THE SYSTEM ADVANCING ACROSS THE
PLAINS EJECTS TOWARDS THE GREAT LAKES REGION AND OCCLUDES
TONIGHT...MEANWHILE BRINGING A DECELERATING COLD FRONT INTO THE
FORECAST AREA. WEAK ISENTROPIC LIFT IS CURRENTLY GENERATING A FEW
SPRINKLES BUT MOSTLY CLOUD COVER. WILL LEAVE SMALL POPS OVER THE
WESTERN HALF OF THE FORECAST AREA TODAY FOR PATCHES OF LIGHT RAIN.
POPS INCREASE THIS EVENING INTO TONIGHT AS THE FRONT ADVANCES INTO
THE AREA. DESPITE THE FRONT DECELERATING WITH THE OCCLUDING
SYSTEM...THE 0-1 KM HELICITIES WILL RANGE FROM 160-210 M2/S2 THIS
AFTERNOON THEN DECREASE GRADUALLY OVERNIGHT WHILE THE FRONT MOVES
INTO THE AREA. NEGLIGIBLE INSTABILITY WILL PRECLUDE A SEVERE
THUNDERSTORM RISK TODAY...BUT SURFACE BASED CAPE VALUES RISE TO
250-600 J/KG OVERNIGHT BUT WHILE THE FAVORABLE SHEAR IS DECREASING.
SPC JUST HAS THE AREA OUTLOOKED FOR THUNDERSTORMS BUT A FEW STRONG
STORMS MAY BE POSSIBLE TONIGHT. WILL LEAVE THE MENTION OF SUCH OUT
OF THE GRIDS FOR NOW BUT WILL NEED TO MONITOR THE AMOUNT OF SURFACE
BASED INSTABILITY. UNSEASONABLY WARM TEMPERATURES CONTINUE THROUGH
TONIGHT. /29

.LONG TERM...(SUNDAY ON)SUNDAY STARTS WITH A FRONT...TRAILING FROM A
SYSTEM OVER THE NORTHERN MISS RIVER VALLEY...STARTING TO MOVE OVER
NORTHWESTERN SECTIONS OF THE FA.UPPER RIDGE IS STILL HANGING TOUGH
OVER THE CARIBBEAN...WITH SOME SHIFTING NORTH TO ENCOMPASS SOUTHERN
FL. THIS SURFACE FRONT MOVES OVER THE FA TO NEAR THE COAST BY SUDNAY
NIGHT AS ITS DRIVING DYNAMICS PULL AWAY. IT ISN`T UNTIL A SHORTWAVE
SYSTEM MOVING SLOWLY EAST OVER THE PLAINS AND LOWER MISS RIVER SUNDAY
NIGHT INTO MONDAY THAT THE FRONT GETS PUSHED SOUTH OF THE FA. GFS IS
A BIT QUICKER WITH THE EASTWARD MOVEMENT OF THE SHORTWAVE...AND THE
FINAL PUSH...RESULTING IN HIGHER POPS IN THE MET MOS FOR MONDAY.
ENSEMBLES ARE TENDING TO AGREE WITH THE GFS TIMING...SO HAVE WENT
THAT WAY WITH THE PRECIP ENDING.

WITH THE UPPER DYNAMICS PULLED AWAY FROM THE AREA AND INSTABILITY
BECOMING MORE LIMITED AS THE FRONT MOVES OVER THE FA...THE RISK OF
ANY SEVERE STORMS RAPIDLY DECREASES SUNDAY MORNING...WITH NO
ORGANIZED SEVERE ACTIVITY EXPECTED BY NOONTIME.

FOR MONDAY NIGHT INTO WEDNESDAY NIGHT...EVERYTHING IS PRETTY TRANQUIL
ON THE WEATHER FRONT...WITH A WEAK RE-ENFORCING FRONT BEING PUSHED
ACROSS THE FA LATE TUESDAY NIGHT INTO WEDNESDAY FROM A SYSTEM PASSING
OVER THE NORTHERN CONUS. FROM HERE...SOME DIVERGENCE OCCURS...WITH
SOME GUIDANCE PUSHING THE RE-ENFORCING FRONT WELL SOUTH OVER THE
GULF(ECMWF) WHILE OTHERS PUSH IT ALONG THE COAST...TO PROVIDE THE
FOCUS FOR ISENTROPIC UPGLIDE SHOWERS OVER THE WESTERN GULF (ECMWF) OR
NORTHWESTERN GULF COAST (GFS). NOT VERY CONFIDENT WITH PRECIP THIS
PERIOD...WEDNESDAY THROUGH THURSDAY...BUT A SYSTEM SWINGING EAST OVER
THE CENTRAL CONUS FRIDAY INTO SATURDAY IS FORECASTING A FRONT PUSHING
OVER THE FA FRIDAY NIGHT.

&&


New Orleans Local Weather thread - dkmac - 12-27-2008 09:11 AM

000
fxus64 klix 270945
afdlix

area forecast discussion
national weather service new orleans la
345 am cst sat dec 27 2008

.synopsis...
Cold front running from nrn minnesota...to near kansas city to
wichita falls texas at 3 am...with surface high centered over the
carolinas.

Over the local area...southeast winds continue to pump moisture into
the area. The difference this morning is that the southeast winds
have brought a low stratus deck to most areas instead of sea fog.
Only site with dense fog at 3 am is boothville...which coincidently
is the cool spot with 64 degrees. Elsewhere...temperatures in the
upper 60s and lower 70s...with dew points in the mid 60s.
&&

.short term...
Main activity will be in the first 24 hours of the forecast. Great
plains cold front will continue to move eastward. Front will move
through the area between 06z and 12z sunday. Convection will
develop in advance of the front. Best support with the front will
be north and west of our area. However...gfs hinting that
conditions may be conducive for a few strong to severe storms in
the western part of our area...if convection can develop prior to
sunset tonight. Gfs sounding for btr shows lifted of -3 with capes
near 1000 j/kg at 21z...and slightly weaker numbers for mcb. Nam
not nearly as bullish...and neither model pinging on severe threat
for new orleans or gulfport areas. Will continue current wording
of hwo...but limit threat to mainly west of interstate 55. Best
chances of precipitation will be overnight ahead of the
front...but severe potential will be diminishing after sunset.

As upper system remains well north of the area...frontal movement
will slow down...and stretch east-west near the coast on
sunday...before finally moving south of the area with the passage
of the next shortwave to the north monday evening or tuesday.

Pops from previous forecast package actually look pretty good
through monday...so no significant changes made. Temperatures will
encroach on records again today...with records for the date of 81
at btr and 80 at msy. Numbers used for current forecast are
uncannily close to 00z mav numbers...and see no reason to go
against them. Calendar day highs for sunday will probably be
before frontal passage...with only about 5 degree recovery after
initial post frontal cooling during the afternoon. Monday highs
should actually be fairly close to normal. 35
&&

.long term...
Gfs and ecmwf are fairly close in solutions through about
wednesday...but after that...go two completely different
directions. Gfs has a stacked upper system centered over chicago
next saturday morning...while ecmwf keeps a more progressive and
open system with a surface now off the massachusetts coast at the
same time. About a 36 mb difference in surface pressures over
chicago at 12z saturday between the models. Ecmwf has more run to
run continuity. Hpc medium range has indicated 00z gfs not favored
for the end of the week...with something close to the 00z ecmwf
used for surface progs.

Resulting surface pattern gives us a dry frontal passage on
wednesday...and another frontal passage with some colder air
behind it on friday. As we will never get in a prolonged period of
onshore winds...will keep pops low with second system for now.
Temperatures for the extended period will be quite a bit closer
to normal than what we have seen recently...but no signs of
unseasonable chill on the horizon at this time. 35
&&

.aviation...
Stronger boundary layer winds have restricted fog and associated
very low ifr conditions to the immediate coastal areas like kgpt
early this morning. This fog should mix out with the ceiling rising
and dissipating by around 15z. Elsewhere...the stronger winds are
keeping vsbys in vfr category and cigs in mvfr category. Satellite
shows some wedges of clearing/scattered decks not too far from kbtr
and kmsy...so the cigs may scatter at times and generally improve to
vfr category mid to late morning. Timing of shra/tsra will be the
next challenge. Highest probability will be over kbtr-kmcb from
evening tonight into early morning sunday...and kmsy-kgpt from
06z-18z sunday. There is a slight risk of strong tsra wind gusts in
35-50 knots range mainly for kmcb-kbtr from late afternoon to around
midnight. 22
&&

.marine...
Areas of fog with visibilities below 1 nm will continue over the
near shore waters early this morning. Otherwise...winds will
gradually veer closer to due south by late morning and increase in
speed to near 20 knots over outer waters and 15 to 20 knots over
inner waters this morning. Have issued small craft advisory for
the outer waters this morning. Northeast movement of surface low
across the mid mississippi valley this afternoon combined with
gradually weakening surface high to the east should allow the
winds to relax slightly to generally less than 20 knots this
afternoon and near 15 knots this evening. However...a longer
period swell train combined with wind waves...already 6 feet at
buoy 42040 and 7 feet at 42001 and 42003...will bring 7 feet seas
to most of the outer waters and portions of the inner waters
around midday and continuing through at least midnight tonight.
Issued /small craft advisory for hazardous seas/ for all coastal
waters from noon to midnight. North winds behind the front don/t
look to be too impressive at only around 15 kts and dropping to
near 10 kts shortly after fropa. High pressure winds will settle
into the region and keep southerly winds relatively light through
mid week. 22


New Orleans Local Weather thread - dkmac - 12-28-2008 08:19 AM

000
fxus64 klix 280924
afdlix

area forecast discussion
national weather service new orleans la
324 am cst sun dec 28 2008

.synopsis...
Frontal boundary has just moved through slidell at 08z...and went
through the new orleans metro area the previous hour. Boundary is
decelerating...but wind shift should clear entire cwa with
possible exception of lower plaquemines parish by sunrise. Areal
coverage of precipitation has been diminishing since midnight with
very few lightning strikes in the last hour over the area.
Observing about a 20 degree temperature fall behind the front with
readings at mcb and btr around 50 instead of the upper 60s to
around 70 ahead of the front.
&&

.short term...
Water vapor loop showing main impulse lifting northeast through
illinois early this morning. Trailing vort over west texas appears
to be shearing out. This means southern portion of front will only
progress very slowly eastward through the day. With precipitation
mainly post frontal...will remove mention of thunder from most
areas today. First period pops will be based on radar trends
shortly before press time. Will need to continue pops across most
of the area through at least mid day on monday before next
vort...currently moving onshore in the pacific northwest...kicks
the front the remainder of the way through the area. Most
precipitation tonight and monday will be across southeast half of
area...and should be relatively light. Going forecast pops appear
reasonable...and are fairly close to mav numbers.

Considering temperature falls behind front...see temperatures
having a tough time reaching mav/met values without seeing any
sunshine. Current forecast appears to be handling slightly better.
While temperatures for the next few days will be considerably
cooler than the last 3...daily averages will still be above
normal. 35
&&

.long term...
Gfs/ecmwf in a little better agreement this morning than
yesterday. Main storm track will remain over northern tier of
states through thursday...before troughing digs a little deeper
across center of the country. A weak cold front moves through
tuesday night into wednesday morning...but with no return flow of
moisture available...this will be more of a wind shift than
anything else.

Return flow is a little better for the frontal system that moves
through on friday as troughing deepens across mississippi river
valley. With upper support so far north...will still only go with
chance pops for thursday through friday night.

Neither model is bringing cold air into louisiana through the 7
days of the forecast...so temperatures will remain near to above
normal through the first weekend of the new year. Beyond
that...models diverge in solutions. 35
&&

.aviation...
Shallow cold front is slowing down as it pushes through coastal
sections of southeast louisiana and mississippi. There should be
enough mixing and slightly drier air to finally clear out the very
low ifr conditions in dense fog and low stratus at kgpt around
10z...however...the shallow nature of the front may cause lifr
conditions to persist until around 12z and ifr until 14z.
Elsewhere...have removed mention of tsra from the tafs as short term
radar trends suggest any lightning will be very isolated and is
steering clear of the taf locations at this time.
Otherwise...lingering mvfr cigs at kbtr and kmsy and ocnl vsby
restrictions in shra can be expected with ocnl ifr conditions at
kmsy this morning. The 00z-12z time period on sunday night/monday
should be vfr at kbtr-kmcb with kmsy-kgpt likely to experience mvfr
to ifr conditions due to lingering low clouds. 22
&&

.marine...
The cold front will be slow to push through the coastal waters
today. An hour or so of n/nw winds 25 to 30 knot has been reported
around lake pontchartrain immediately behind the cold front...and
this and lingering fog have been handled with a marine weather
statement. Otherwise...winds in the wake of the front will remain
below small craft advisory criteria. Offshore flow behind the front
will continue through monday. Return flow of generally light
southerly winds begins tuesday for a brief period of time...then
another cold front moves across the coastal waters tuesday night and
wednesday bringing a return to offshore flow. 22