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Area forecast discussion 
National Weather Service New Orleans la
342 PM CDT Tuesday Jul 26 2016


Weak surface low appears to be sitting between the Atchafalaya
River basin and Lake Pontchartrain. Weak upper low just off the
southwest Louisiana coast. Numerous showers and thunderstorms
were rotating around the surface low, with the thunderstorms
primarily west of Interstate 55. Areas that have not received rain
have generally reached the upper 80s to around 90, but rain will
drop temperatures into the upper 70s.


Short term...

Upper feature off the coast should lift to near the Arkansas-
Louisiana border tomorrow before the westerlies pick it up and
carry it northeast. A weakness will remain in the upper pattern
across the area through the end of the week. Will hold on to
likely rain chances for a few hours this evening before it
diminishes. Likely chances again tomorrow, but with main impulse
lifting north of the area, rain chances somewhat lower for
Thursday and Friday. High temperatures next several days likely to
occur near midday, as convective temperatures are reached and
thunderstorms develop. Little difference in forecast guidance, and
have not made significant changes. 35


Long term...

Weakness in upper pattern remains through the weekend into early
next week. That means continued daily development of scattered
showers and thunderstorms through the extended period. Rain
chances may decrease slightly late in the weekend, allowing for
high temperatures to warm a degree or two, but no major changes.



Scattered to numerous showers with some embedded thunderstorms will
continue to affect the area through at least the first part of this
evening with some lingering showers likely lasting through the night.
Have included vicinity and tempo groups for the most likely impact
times. Outside of any convective activity, conditions should
generally remain VFR or MVFR.



The weak surface low has tightened the gradient enough over the
open coastal waters to necessitate a Small Craft Advisory for all
of the open waters into this evening. Convection has been
producing occasional 30+ knot gusts at some of the AWOS sites on
oil platforms, most of which are 100+ feet above the water
surface. Also seeing a few gusts that do not appear to be
convectively related that are exceeding 34 knots, but do not think
these are going to be widespread. Expect these winds to ease
somewhat after sunset. Beyond tonight...expect somewhat quieter
conditions across the waters through the end of the week. 35


Decision support...

Dss code: green.
Deployed: none.
Activation: none.
Activities: none.

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.
Yellow = heightened impacts with short-fused watch, warning
or 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 of severe and/or
direct tropical threats; events of National significance.


Preliminary point temps/pops...
mcb 73 88 73 90 / 50 70 50 50
btr 74 90 74 91 / 60 70 50 40
asd 76 91 77 91 / 60 70 50 40
msy 77 90 78 91 / 60 60 50 40
gpt 77 90 78 91 / 60 70 40 30
pql 77 90 77 91 / 60 60 40 30


Lix watches/warnings/advisories...
GM...Small Craft Advisory until 9 PM CDT this evening for gmz550-552-

GM...Small Craft Advisory until 9 PM CDT this evening for gmz552-555-



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