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Area forecast discussion 
National Weather Service New Orleans la
1123 am CST Friday Nov 27 2015

VFR conditions are expected through at least 04z before some
marine layer cloud decks develop and spread over the
region...settling into IFR and localized LIFR ceilings between 06z and
14z...then improving through MVFR to low end VFR by 28/18z. 24/rr


Previous discussion... /issued 413 am CST Friday Nov 27 2015/

Discussion... surface high pressure continues to dominate weather
conditions across the area. This ridge is currently encompasses the
entire southeastern United States. A surface trough is draped over
the central Continental U.S. From the Great Lakes southwestward to central
Texas and then to the Permian Basin of West Texas. In the upper
levels...ridge centered around the Bay of Campeche extends northeast
to the central Gulf Coast while upper low are in place to the east
over the Bahamas and to the west near Nevada. The local County Warning Area remains
in mild and humid conditions with high pressure aloft keeping
daytime highs in the 70s and rain chances to a minimum. There area
few echos showing up on radar and the hrrr does depict a few showers
today but thinking the coverage will be to low to have any mention
of rain in the zone forecast today through Saturday.

The upper level low currently centered west of The Rockies will
gradually rotate east through the weekend. This slower movement will
keep the cold front currently to the north nearly stationary well
northwest of the County Warning Area. Models show that this frontal boundary will
finally start moving into the local region early to middle of next
week as the upper low begins tracking more briskly east across the
Central Plains. The east to east-northeast track of this low will result in a
stretching front as it moves in which is typically a fairly low
impact event with minimal thunder threat and generally lower rain
coverage. In not have any thunder in the extending forecast at
all. The progression of slight chance to chance probability of precipitation will be fairly
slow from northwest to southeast. This run models are even slightly slower
than previous with northwestern zones not seeing any rain until late Sunday.
Even as the boundary moves through Tuesday it is entirely possible
that many locations in the County Warning Area do not see rain at all. The European model (ecmwf) is
on the wetter side however with pop guidance in the 50 to 70 percent
range vs mex which is not even half that. Kept the long term forecast
close to the previous which is on the drier side of model guidance.


Aviation... not a lot of difference between last 24hr and the next.
Ceilings will remain in the 1.5k feet area this morning and rise to
around 2-3k feet during the day today but will be intermittent as low
level clearing will give way to decks around 12-15k feet. Tonight will
be about the same as ceilings will fall once again to around 1.5k feet
but some areas will be in and out of the low level decks. Winds will
be very weak to calm overnight. If low level ceilings clear for a
time there may be some light fog formation. Will show this as a
tempo group toward the end of the 12z taf pack but only bring down
to around 3sm.

Marine... high pressure over the Atlantic coast line will be slow
to move through the end of the week. Guidance has come in a little
slower with the progression of storm system and high pressure
breaking down and will maintain current forecast with a few minor
tweaks. A cold front will progress southeastward and stall near
Texarkana today. As a result...the strong pressure gradient will
remain over the southern US and Gulf coastal waters. Easterly winds
will remain elevated today then shift to southeast into the weekend.
The cold front is expected to move to the coast and stall again by

Decision 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 risk severe and/or direct
tropical threats; events of National significance


Preliminary point temps/pops...
mcb 74 58 74 59 / 10 10 10 10
btr 77 62 77 61 / 10 10 10 10
asd 74 59 74 58 / 10 10 10 10
msy 76 63 75 61 / 10 10 10 10
gpt 73 58 72 57 / 10 10 10 10
pql 75 57 74 54 / 10 10 10 0


Lix watches/warnings/advisories...
GM...Small Craft Advisory until 6 PM CST this evening for gmz552-555-

Small Craft Advisory until noon CST today for gmz536-538-550-557.

GM...Small Craft Advisory until 6 PM CST this evening for gmz555-570-

Small Craft Advisory until noon CST today for gmz538-550-557.



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