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Area forecast discussion 
National Weather Service New Orleans la
334 PM CDT Wednesday Jul 30 2014

Short term...

The dry and stable airmass that has dominated the region today
will unfortunately begin to move out of the area late tonight into
early tomorrow. At the same time...a fairly strong upper level
vorticity maximum and associated frontal boundary will approach the region
from the northwest. Ample moisture as indicated by radar and
satellite returns over the Southern Plains will advect into the
region. Moisture will increase aloft initially and then work down
to the surface through the day tomorrow.

Expect to see increasing cloud cover through the day and the
Prospect of some scattered convection developing during the
afternoon hours over far northwest zones. More isolated convection
will develop by late afternoon over the southern half of the
forecast area. The vorticity lobe descending down the backside of a
strong longwave trough dominating the eastern third of the nation
will move into the lower Mississippi Valley on Friday. Ample
forcing combined with deep moisture will allow for scattered
convection to develop across the forecast area. Precipitable water values will be
around 2 any rainfall could be potentially heavy due
to the slow storm motions of around 5 knots expected. The airmass
will change little going into Saturday...and expect another round
of convection to develop in the vicinity of the front.
However...expect less overall coverage as precipitable water values are slightly
lower and the vorticity lobe aloft lifts to the north and east of the
region. Have lowered probability of precipitation about 10 percent from the previous
forecast. With increased cloud cover and precipitation in the
area...expect temperatures to remain around 5 degrees below

Long term...

Conditions will be little changed from Sunday through a slowly dissipating frontal boundary over the region
interacts with a persistent upper level trough and continued
higher than average upper level lift. Ample moisture will still be
in place...with model soundings showing precipitable water values still around 2
inches and a moist adiabatic profile in place. With slow storm
motions of 5 knots or less and deep tropical moisture over the
area...any convection will have the potential to drop heavy
rainfall over isolated areas. This could continue to keep a
localized street flooding threat in place over the area. Once
again...the convective threat will be greatest during the
afternoon hours when overall instability is highest. Temperatures
will remain around 5 degrees below average through Tuesday due to
the continued rainfall and cloud cover.

The trough over the eastern third of the country will begin to
break down a bit and the subtropical ridge will extend westward
from the eastern Gulf of Mexico on Wednesday. With less Omega in
place and slightly lower precipitable water values closer to 1.8
inches...convective coverage should decrease a bit. Have put in
chance probability of precipitation...but the pop is closer to 40 percent as opposed to 50
percent for Wednesday. Temperatures should also increase back to
more normal levels by the middle of next week.



Dry air across the area will keep VFR conditions in effect at all
terminals through 18z Thursday. The atmosphere will moisten up from
the top down and from northwest to southeast Thursday
afternoon...possibly bringing some isolated to scattered shra/tsra.
Confidence and location is too low for any mention today...but this
will have to be considered with later taf issuances. 22/dew point



No significant marine impacts are expected through the forecast
period. Winds will generally be 10 knots or less and will be
variable as a frontal boundary stalls along the coast. Seas will
generally be 1 foot or less through the weekend. The biggest
boating impacts will be associated with convection. Thunderstorms
will bring a gusty wind and lightning hazard to the coastal waters
each day. 32


Decision support...

Activities...slurry support.

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 to high risk severe
and/or direct tropical threats; events of National


Preliminary point temps/pops...
mcb 64 87 69 87 / 10 30 30 50
btr 65 89 72 89 / 10 30 30 50
asd 64 88 69 88 / 10 20 20 40
msy 72 88 74 87 / 10 20 20 40
gpt 66 90 68 90 / 10 20 20 40
pql 62 88 67 88 / 10 20 20 40


Lix watches/warnings/advisories...



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