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Area forecast discussion 
National Weather Service New Orleans la
417 PM CDT Wednesday Jul 27 2016


Weak low near the Arkansas-Louisiana border this afternoon. Bands
of showers and a few thunderstorms continue to rotate through the
area with occasional wind gusts to 25-30 mph as they move through.
Temperatures have remained in the 70s to lower 80s across the
northwest half of the area, but have made it into the upper 80s
along the Mississippi coast.


Short term...

The low near the Arkansas-Louisiana border will get picked up by
the westerlies on Thursday and leave the local area in a col,
which should significantly limit the development of precipitation
tomorrow. This is also reflected in lower precipitable water
values on forecast soundings. Have backed down the rain chances
Thursday from previous forecast packages, and would not be
surprised if the mid shift backs them off a little more. With more
sunshine expected, high temperatures should return to the lower
90s on Thursday.

Beyond Thursday, we remain in between The Four Corners ridge and
the Bermuda high, which will allow the normal diurnally induced
convection. Will carry chance/scattered pops for Friday and
Saturday with highs in the lower 90s and lows generally in the mid
and upper 70s. 35


Long term...

For early next week, medium range models attempt to bring Four
Corners ridge back into the middle of the country. Some
differences exist between GFS and European model (ecmwf). GFS tries to bring a
series of easterly waves through the Florida Straits that would
bring organized convection to the coast by mid-week. European model (ecmwf) has the
ridge more centered over the arklatex area, which would start to
dry/heat things up again. For now, will continue previous forecast
trends of daily diurnal convection, but will continue to monitor
the situation. 35



Convective coverage continues to diminish this afternoon with just
some decaying anvil precipitation to remain through 00z. VFR
conditions expected overnight though some sct020-025 marine layer
clouds may advect closer to daybreak. Less coverage of convection
expected Thursday due to location of col aloft, inhibiting much
cellular growth of any towers attempting to develop, hence general
VFR conditions through 00z Friday. 24/rr



Aside from convection generating along an old outflow boundary,
which is likely strewn with weak waterspouts, winds and seas should
remain rather low. Gust potential still remains 25-35 kt from
convection, but may be closer to 40kt along the outflow feature in
the coastal waters between Mobile Bay and the mouth of the
Mississippi River. 24/rr


Decision support...

Dss code: green.
Deployed: none.
Activation: none.
Activities: Jefferson Parish public safety support for Grand Isle.

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 72 93 73 93 / 40 40 30 50
btr 73 93 73 92 / 40 30 30 50
asd 76 92 77 91 / 30 20 20 40
msy 77 93 78 90 / 30 20 20 40
gpt 78 91 78 90 / 30 20 20 40
pql 77 92 77 90 / 30 20 20 40


Lix watches/warnings/advisories...


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