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fxus64 klix 240829 
afdlix

Area forecast discussion
National Weather Service New Orleans la
329 am CDT Mon Jun 24 2019

Short term...
early this morning, regional radars show a line of thunderstorms
along a line from Natchez to Toledo Bend moving southeast. These
storm should be reaching the northwestern corner of the County Warning Area in
southwest Mississippi within the next hour or 2. Based on lightning
data, general intensity along the portion of the line that will
impact the local area has been decreasing. Strong to marginally
severe storms are possible with gusty winds being the main threat.
Global and many meso models are not doing a good job depicting the
fast progression of this line. The hrwarw initializes quite well
and bring the lead edge of the convection through msy by mid
morning. Thus, have adjusted short- term probability of precipitation to be much closer to
that solution along with rain chances decreasing considerably
with time after 18z. The one thing that most models have in common
in a general decrease in the integrity of the line as it moves
across the forecast area. This makes sense with lightning already
falling off. One ramification of earlier convection is the
likelihood of much cooler daytime highs that previously
forecasted. Have dropped todays highs done into the mid 80s to 90.



Moving into Tuesday, an upper level ridge will try to build across
the Gulf of Mexico from the western Atlantic while a weak shortwave
tracks across East Texas, Arkansas and northern Louisiana. This will
bring increased rain chances to at least the north an northwestern
portions of the forecast area. For now, limited appreciable probability of precipitation to
those areas north of a hum to asd line. A rebound of daytime temps
is expected tomorrow as well with highs back in the lower to mid
90s.

The remainder of the week will be characterized by upper level ridge
building across the southern half of the country from Texas to the
East Coast. It will be a daily battle between daytime heating
induced convection and subsidence aloft. The European model (ecmwf) suggests the
downward motion will suppress most of the convection while the GFS
says the daytime heating will win out and scattered to numerous
storms will develop. Went in between those 2 with the pop forecast,
leaning towards the GFS for Friday as the ridge locally should begin
its weakening trend.

Long term...
that weakening will continue into the weekend as a deep trough
tracks out of Canada across the northeastern conus, eroding the
ridge across the southeastern US. This will allow strong daytime
heating to produce numerous afternoon thunderstorms. Expect this
summertime pattern to persist into at least the first half of next
week.

Meffer
&&

Aviation...

Conditions will be variable between MVFR and VFR depending on taf
location this morning. Have timed out the arrival of line of sh/ts
for kbtr/kmcb during the 12-15z period and khdc 13-16z with lower
visibility and higher convective gusts. Remainder of airports to east and
south are more uncertain on whether the integrity of the rain showers/thunderstorms and rain
will be maintained, so only carried p6sm -shra thunderstorms in the vicinity at this time.
For later morning hours. Conditions improve slightly the remainder
of the day with respect to ceilings and rainfall will remain light
as well and even slowly ease through the day.

&&

Marine...

Moderate southerly flow remain in place and will remain so through
tonight. By Tuesday high pressure moves over the area and this will
lead to a break down of the winds over the coastal waters with winds
mainly controlled by diurnal fluctuations. Seas will behave with 2-4
feet through tonight lowering to 1-3 after that. Still looks like
conditions begin to become more favorable for nocturnal storms over
the coastal waters mid and late next week.

&&

Dss code: blue.
Deployed: none.
Activation: none.
Activities: river flood warnings

&&

Preliminary point temps/pops...
mcb 86 73 92 72 / 80 30 30 30
btr 89 75 92 74 / 90 20 30 20
asd 90 76 94 75 / 70 20 10 20
msy 90 78 94 78 / 70 10 10 10
gpt 88 78 91 77 / 70 10 10 20
pql 90 77 93 75 / 60 10 10 20

&&

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

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