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Area forecast discussion 
National Weather Service New Orleans la
934 am CDT Friday may 29 2015


No significant changes to the forecast for today. Have adjusted
probability of precipitation slightly for this afternoon...but still keep chance probability of precipitation in
place for most of the area. Temperatures are warming a couple of
degrees faster than expected...but not enough of a difference to
make note of. For this evening and overnight...have adjusted probability of precipitation
down for late evening...but then expect to see probability of precipitation increase over
the western zones late tonight as a band of convection potentially
approaches from the west. 32


Previous discussion... /issued 312 am CDT Friday may 29 2015/ was fairly quiet yesterday with only isolated
activity...pretty much as expected. The rather quiet weather
continued into the overnight hours and conditions were quiet muggy. At
6z most sites were still in the lower to middle 70s. Temperatures should
continue to slowly fall with morning lows likely ranging from upper
60s to lower 70s.

There will be more activity today than yesterday. First moisture
will recover some with precipitable waters likely increasing to near 1.6 by early
afternoon. In addition an 850 mb Theta-E surge will work across the area
from the Gulf. The ridging that was over the region yesterday will
has already begun to be suppressed and pushed out to the east. The
disturbance/troughing associated with the convection over central Texas
will be moving twrds the lower MS valley today and begin to put the
area under SW flow aloft. With the increase in
lift/support...increase in moisture...and diurnal heating we should
see scattered afternoon convection today.

Heading through the weekend middle level trough will set up over the
region and even deepen by sun. This will continue to lead to
convection each day with probability of precipitation slightly increasing with each
respective day. By sun the deepening trough...divergence aloft...and
abundant moisture should lead to num rain showers and thunderstorms and rain.

Sun and through the first half of next week...we still look like we
could be in a wet pattern. All of the medium range basically agree
(of course some minor timing and placement issues) that the base of
the trough will eventually close off over the lower MS valley and
could even dig into the northern Gulf. This would basically keep things
active from a standpoint of rain but luckily it should help keep
storm intensity down. So next week look for mainly a wet and
slightly cooler forecast. /Cab/

Aviation... low ceilings are expected through 14z before lifting as
an inversion mixes out. Some patchy fog is also expected with the
low level ceilings and have visibilities falling to 3 miles for a
brief period. With ceilings developing around 6k feet later
today...expect low ceilings to be very transitory and should not
have to show any in 12z taf pack. Visible restrictions would be around
2sm if the middle level deck clears for a while. But this 6k feet deck is
not expected to clear for long periods.

Marine... east to southeast winds will remain over the coastal waters
through the forecast. Isolated to scattered thunderstorms will be
possible each day. Wind speeds will ease to light and variable for
many areas Monday and Tuesday but should still keep a general southeast
flow overall.

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 86 68 84 68 / 40 40 50 40
btr 87 70 85 70 / 40 40 50 40
asd 85 71 85 71 / 40 40 30 30
msy 86 73 85 72 / 30 30 30 30
gpt 84 73 85 72 / 40 30 30 20
pql 85 70 85 70 / 30 30 20 20


Lix watches/warnings/advisories...


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