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Area forecast discussion 
National Weather Service New Orleans la
331 am CDT Tuesday Jun 30 2015

Synopsis...

Bermuda high remains in place...exerting influence over a good
portion of the Gulf of Mexico. Wide upper trough covers much of the
eastern half of the country with a closed upper high over Utah.
Weak stationary fronts are located along the Carolina coast and
over the Ohio River valley. Locally...the remnants of an evening
mesoscale convective system are producing a few sprinkles across northern portions of the
area. Scattered showers are indicated by radar over southwest
Louisiana and the western Gulf of Mexico. Quite a bit of upper
cloud debris from the evening mesoscale convective system is holding up temperatures over
the southeast half of the area...where outflow from the mesoscale convective system never
reached. Those areas still have temperatures and dew points in the
middle and upper 70s...while areas to the north have temperatures in
the lower 70s and dew points in the upper 60s.

&&

Short term...

Impulses rotate through the base of the upper trough today and again
on Wednesday. With abundant moisture remaining in place...a repeat
of scattered convection is anticipated...mainly from late morning
through the afternoon hours both days. A few storms could be
strong to severe today...mainly over northern portions of the
area per Storm Prediction Center day one convective outlook. Bermuda high attempts to
build a bit westward on Thursday...bringing somewhat drier
conditions to the area...especially on the NAM and European model (ecmwf)
solutions. Will limit precipitation mention on Thursday to the
Mississippi coastal counties.

Temperatures will generally top out within a few degrees of the 90
mark today and Wednesday...with a few temperature busts where
convection develops early. Thursday high temperatures will be a
couple degrees warmer due to less cloud cover/convective coverage.
35

&&

Long term...

Local area remains in somewhat of a weakness between the upper
level highs to our east and west. Friday still looks mostly dry
across the area. The upper trough is considerably weaker in the
extended period than currently...so areal coverage of diurnally
forced convection will be somewhat less for the weekend into early
next week than what we have seen the last day or two...but still
in chance range for most of the area. High temperatures in the 90
to 95 range with lows in the 70s should be common through the
period. 35

&&

Aviation...

Isolated to scattered afternoon convection will continue...so will
include tempo thunderstorms and rain in most taf sites through 23z. Expect mainly VFR
conditions through Wednesday morning. Exceptions will be at kmcb
where IFR/LIFR will be again possible early this morning/mainly from
low stratus/...and at kbtr...khdc and khum where tempo MVFR
conditions from ceilings and/or visibilities will be possible. 17

&&

Marine...

An expansive ridge of high pressure over most of the Gulf of
Mexico...extending west from the typical summertime Bermuda
ridge...will remain in place through the week. Not expecting any
substantial disturbances passing south of the ridge in the
easterlies...nor any frontal boundaries or lows passing across the
Gulf Coast states that will have a significant impact on winds and
waves. Therefore...southwest winds will remain. Expect moderate
pressure gradient to support around 15 knots winds over some of the
eastern coastal waters for this afternoon...and Wednesday east of
the Mississippi River. Wind direction will be mostly southwest to
occasionally south the remainder of the week. Wave heights are
expected to be 1 to 3 feet. 17

&&

Decision support...

Dss code....blue.
Deployed...none.
Activation...none.
Activities...river flood warnings on Mississippi River from Red
River Landing to Baton Rouge. Monitor convective
trends.

Decision support services (dss) code legend
green = no weather impacts that require action
blue = long fused watch/warning/advisory in effect or high
visibility event
yellow = heightened impacts with short fused watch/warning/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 severe and/or direct
tropical threats; events of National significance

&&

Preliminary point temps/pops...
mcb 89 72 90 74 / 50 20 40 10
btr 91 73 91 76 / 40 20 40 10
asd 90 76 91 77 / 40 20 40 10
msy 91 76 91 78 / 30 20 50 10
gpt 89 77 89 78 / 50 20 30 20
pql 89 74 89 77 / 50 20 30 20

&&

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

$$

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