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fxus64 klix 152037 
afdlix

Area forecast discussion
National Weather Service New Orleans la
337 PM CDT Sat Jun 15 2019



Short term (today through tuesday)...

The transition to a more typical Summer pattern started today as a
surface ridge has built into the southeast U.S. Daytime providing
a light south to southwest flow in the mid levels increasing low
level humidity with dew points reaching into the lower 70s.
Daytime heating convection initiated on the coast and progressed
steadily inland during the afternoon under generally light but
steady southerly low to mid level flow. Thunderstorm activity
should diminish by early evening with loss of daytime heating. GFS
model sounding indicate precip water edges up to around 1.8
inches on Sunday...so expected a similar day on Sunday with
scattered showers developing later morning and spreading inland.
Temperatures will be near seasonable normals.

Monday and Tuesday rain chances should increase in the 60 to 70
percent range most areas as the region is affected by a short
wave trough evident in the 700-500mb GFS model guidance that
tracks from OK to the Ohio Valley. Combination of daytime
heating...influence of mid level trough...and ample moisture and
instability with precip water in the 1.8 to 1.9 range should allow
for ample shower and thunderstorm coverage on Monday and Tuesday
from late morning into afternoon...with some convection lingering
into the evening. Max temperatures may be tempered slightly due
to shower and thunderstorm.

Long term (wednesday through saturday)...

Have maintained daily chances of showers and thunderstorms through
the remainder of the week as ample deep level moisture remains in
place. The earlier mentioned short wave trough will lift away
from the area on Wednesday...with rain chance slightly lower.
Another short wave trough moves through the westerlies on Thu
across the Ohio and Tennessee Valley though it may be close enough to
influence the rain chance locally with a slight increase in
thunderstorm coverage on the Thu and Thu night. After this
shortwave moves east of the area...high pressure at mid and low
levels begins to build into the area which should lower rain
chances at the end of the week and first part of the weekend. Max
temps should range from the upper 80s to low 90s...and be highly
dependent on daily shower and thunderstorm coverage. 21



&&

Aviation...
will carry tempo thunderstorms and rain at kmsy, kasd, and kbtr this afternoon and the
others sites thunderstorms in the vicinity. Expecting south to southeast winds up to 10 knots
with some gusts this afternoon at most sites. Convection should
decrease by 23z with VFR conditions this evening through Sunday
morning. Isolated convection is expected to develop around 17z
Sunday. 18

&&

Marine...

Onshore flow will continue through the entire forecast period as
surface high pressure takes hold over the Atlantic southeastern
coast. Onshore winds will increase to 15 to 20 knots in the
offshore waters by midweek as gradient tightens slightly with an
approaching boundary to the north alongside surface high remaining
along the southeast Atlantic and eastern Gulf. 18

&&

Decision support...
dss code: blue.
Deployed: none.
Activation: none.
Activities: flood warnings continue along the Mississippi and
Atchafalaya rivers.

Decision support services (dss) code legend green = no weather
impacts that require action.
Blue = long-fused watch, warning, or advisory in effect or high
visibility event; marginal risk severe or excessive rain.
Yellow = heightened impacts with short-fused watch, warning or
advisory issuances; radar support for slight risk severe or
excessive rain.
Orange = high impacts; enhanced risk severe; nearby tropical
events; hazmat or other large episodes.
Red = full engagement for moderate to high risk of severe and/or
excessive rain; direct tropical threats; events of National
significance.

&&

Preliminary point temps/pops...
mcb 71 91 71 89 / 20 40 20 60
btr 73 91 73 89 / 20 40 10 70
asd 73 91 73 90 / 20 30 10 50
msy 76 91 77 90 / 20 30 10 60
gpt 74 88 74 87 / 20 20 10 40
pql 72 90 71 89 / 20 20 10 30

&&

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

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