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fxus64 klix 252052 
afdlix

Area forecast discussion
National Weather Service New Orleans la
352 PM CDT Tue Jun 25 2019

Synopsis...
latest surface analysis showed a 1019mb high over north central
and northeast Gulf of Mexico and weak pressure gradient of 1mb
change from Mississippi coastal waters to the mid-south. Surface
dewpoint values remained in the 70s across southeast Louisiana and
southern Mississippi. A light southwest flow was noted over the
forecast area, slightly higher wind speeds near the coast and
south of Lake Pontchartrain.

Upper air analysis showed a negatively tilted low/trough axis
north the Great Lakes region and westerly flow over from the
plains to Ohio Valley. In addition, a positively tilted trough
axis was located from north Louisiana to south Texas and a high
over northeast Gulf and Florida Panhandle. Precipitable water
values on a planer view indicated a moisture axis of 2 inches
along the Texas coast 1.6 to 1.8 inches southwest Louisiana to
Florida Panhandle.



&&

Short term...
with the trough axis in the northern stream lifting Northeast,
Heights will generally increase over the southeast Continental U.S.. this
movement will allow the upper level high over northeast Gulf to
drift northwest over the forecast area through Thursday. This will
suppress general motion upward motion. However, 5h temps around
-9c will slowly decrease to -10c. As a result, rain chances will
be slightly below norm on Wednesday but isolated to scattered
storms can not be ruled especially across the northern zones.
Ridge axis will reestablish over the plains on Friday leaving a
weakness from Louisiana to Georgia. However, mid layer flow will
become northwest to northeast Thursday and Thursday evening a few
strong storms with gusty winds can not be ruled out.



Long term...

Weakness will try to develop into the inverted trough in the mid
layer and possibly a broad cyclonic circulation over the central
Gulf Coast. Precipitable water values will increase to up to 1.8
inches Friday afternoon. As a result, rain chances will increase
to 50 to 60 percent on Friday. Weak upper level trough/low will
continue to shift east and maintain elevated rain chances on
Saturday. Upper level trough/low will continue to the shift west
allowing a ridge to slowly build into the central Gulf Coast
Sunday through Tuesday of next week. Rain chances will decrease a
tad, actually back to normal Summer time 30 percent for next week.

Aviation...

Generally VFR conditions are expected for the forecast period.
Isolated summertime pulse storms are possible at several terminals,
and will show this with thunderstorms in the vicinity in tempo groups mainly kmcb and kbtr.

&&

Marine...

Surface high pressure will move 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 also subside to 1-2ft
as well. Still looks like conditions begin to become more favorable
for nocturnal storms over the coastal waters mid and late next week
as at least one easterly wave moves through the Gulf.

&&

Decision support...
dss code: blue.
Deployed: none.
Activation: none.
Activities: Mississippi River flood warnings
marginal risk of severe weather this afternoon.

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 rainfall, or direct tropical threats; events of
National significance.

&&

Preliminary point temps/pops...
mcb 89 71 93 70 / 40 30 20 20
btr 89 74 93 73 / 40 30 20 20
asd 92 74 93 73 / 30 20 20 20
msy 92 77 93 77 / 30 20 20 20
gpt 90 76 92 75 / 30 20 20 20
pql 92 74 95 72 / 20 10 20 20

&&

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

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