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Area forecast discussion
National Weather Service New Orleans la
356 PM CDT sun Mar 26 2017

Short term...much quieter day today. A little fog and low clouds
early this morning quickly gave way to mostly sunny skies and warm
afternoon temperatures. Temperatures were already in the upper 70s
to lower 80s by 18z and we should continue to see another 1-3
degrees of warming by the end of the afternoon.

First issue in the next 60 hours will be tomorrow but overall
things just don't look to promising for rain. Tonight will be
quiet with the system that is producing the severe weather over
the Southern Plains pushing east into the Ozarks. Problem for rain
tomorrow is the best support comes in early Monday. Best upper lvl
divergence, mid lvl speed Max, and torugh axis all come through
b/T 12 and 18z. After all of this pushes east/northeast mid lvl
hghts rise and then the cold front slowly approaches along with
some afternoon heating. Maybe the proximity of the front and
daytime heating can spark a few thunderstorms. Best chance for
rain will be north of the 10/12 corridor and this may be a little
optimistic.

As for Monday night and Tuesday it looks like we may have to deal
with fog as the cold front stalls north of the area. The system
Monday will quickly move into the Ohio/Tennessee valleys. As this happens
mid lvl ridging will be left in its place across the lower MS
valley. This along doesn't Bode to well for rain but for some
reason the mdls are trying to print out some very light apf b/T 12
and 18z Tuesday. The thinking is that this could just be fog and
low clouds so will keep most of the area dry with the exception of
token 20% near southwest MS. As for the fog Tuesday morning it
could be dense in a few areas. Moisture will continue to increase
as we remain south of the front. Winds in the low lvls will be
weakening through the night and if there is any rain from Monday
the risk for fog will increase. /Cab/

Long term...Wednesday will be rain free and very warm as deep
southwest flow takes root ahead of a potent 500 mb trough. Storms
are expected to develop across Texas, will will track into la
Wednesday night. Rain chances do not begin to go up across
southeast la and south MS until late in the night Wednesday into
early Thursday morning. The storms will likely be weakening at
that time. Restrengthening and development of storms should take
place Thursday with daytime heating and as the base of the upper
trough arrives. Strong southerly low level flow under westerly
winds aloft suggest favorable shear for some of the storms to be
severe.

For Friday into most of Saturday dry weather is expected from
ridging aloft that develops over the central Gulf Coast. Another
even deeper trough extending into northern Mexico will begin to
anchor to the west. Despite the uncertainity with being towards the
end of the forecast period, the western trough does appear to place
the central Gulf Coast in a long duration period of southwest flow.
More storms and maybe even a heavy rain threat beginning Saturday
night through Monday may set up as ample moisture streams in.

Krautmann

&&

Aviation...

VFR conditions will persist through around 06z. After 06z, a low
level inversion will develop allowing for another round of low
ceilings and fog to impact the terminals. Ceilings should bottom out
at around 300 feet and visibilities should generally range from 1 to
3 miles. However, kmcb could fall to around one half mile for a few
hours. As a result, LIFR and vlifr conditions will be possible at
all of the terminals from 08z through around 14z. After 14z,
conditions should improve into MVFR range of around 2000 feet.

&&

Marine...

A weaker pressure gradient over the Gulf will keep southerly winds
of around 10 to 15 knots in place through Tuesday. Seas should also
be much calmer at 2 to 4 feet during this period. By Wednesday, an
approaching low pressure system will result in an increased pressure
gradient over the coastal waters. Expect to see onshore flow
increase to 15 to 20 knots on Wednesday, and then further increase
to 20 to 25 knots and Small Craft Advisory range by Thursday. Seas
should also increase to 4 to 7 feet in the open Gulf waters during
this period. By Friday, the low should be well east of the area,
and the pressure gradient over the Gulf will relax. A lighter west
winds of around 10 knots should take hold, and seas should begin to
drop off. 32

&&

Decision support...
dss code...green.
Deployed...none.
Activation...none.
Activities...none.

Decision support service (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 of severe weather;
nearby tropical events, hazmat or other large episodes
red = full engagement for moderate risk of severe weather; direct
tropical threats; events of National significance.

&&

Preliminary point temps/pops...
mcb 64 84 64 84 / 10 30 10 20
btr 66 84 66 86 / 10 30 10 10
asd 66 82 65 83 / 10 20 10 10
msy 68 83 67 84 / 10 10 10 10
gpt 67 79 66 80 / 10 30 10 10
pql 65 79 65 81 / 10 30 10 10

&&

Lix watches/warnings/advisories...
la...none.
GM...none.

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