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Area forecast discussion 
National Weather Service New Orleans la
406 am CDT Sat Aug 23 2014

Short term...
only real issue for today will be warm temperatures and heat index
values in the 105-110 range most locations this afternoon. Per
local guidance and policy of utilizing the synoptic health watch-
warning network...which accounts for cumulative effect of
excessive heat...today will make day one of a moist tropical+
/mt+/ air mass. Sunday's temperatures will be indicated to be a
degree or two warmer than today and also make day two of mt+
conditions...worthy of an excessive heat watch. The models are
suggesting...for various reasons...some nocturnal rainfall moving
from the east into the forecast area Sunday night that would
effectively end the string of mt+ conditions. The NAM is
indicating a well estabished easterly wave that may actually be an
emanation of energy from invest 96l...the GFS is showing an impulse
rounding the fringe of the ridge from Alabama...through coastal
Mississippi into eastern la prior to sunrise. The European model (ecmwf) is less
ambitious with the rain coverage...confined mainly over Jackson Colorado
MS. Have opted to go closer to GFS idea of impulse driven
convection developed in high Theta-E air with plenty of outgoing
longwave radiation to work with late evening and overnight Sunday
night.

Long term...
the center of the high is expected to become oriented along the
eastern Seaboard and extending into the Gulf states for a period
of deep easterly flow Tuesday...possibly tainted by some fringe
moisture tapped from invest 96l or eventual tropical system east
of the U.S. Coast. Otherwise...typical temperatures and rain
chances expected Tuesday through Friday. 24/rr

&&

Aviation...
expect VFR conditions to continue through the forecast period. There
has been some light patchy fog this morning in a few spots but
widespread fog is not expected. Convective chances rather
small...have elected not to mention thunderstorms in the vicinity in this issuance since the
coverage yesterday was so limited. 13/mh

&&

Marine...
high pressure remains in place over the coastal waters. This high
will remain in place through the weekend. Seabreeze/landbreeze cycle
will dominate. Expect offshore winds in the morning hours and
onshore winds developing during the afternoon hours. Winds and seas
should remain fairly benign. Winds will generally be 10 knots or
less and seas will generally be 2 feet or less. Winds will take on a
more persistent easterly flow early next week as the surface high
becomes centered north of the region. East winds of 10 to 20 knots
and seas of 3 to 5 feet can be expected late Monday night through
the middle of next week. 13/mh

&&

Decision support...
dss code...green.
Deployed...none.
Activation...none.
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
significance.

&&

Preliminary point temps/pops...
mcb 96 73 98 74 / 20 20 10 20
btr 96 75 99 77 / 20 20 10 10
asd 95 75 97 77 / 20 20 20 20
msy 95 79 96 80 / 20 20 20 20
gpt 95 77 97 78 / 20 20 20 20
pql 96 74 98 75 / 20 20 20 20

&&

Lix watches/warnings/advisories...
la...excessive heat watch from 11 am Sunday to midnight Monday for
the following zones: Ascension...Assumption...East Baton
Rouge...East Feliciana...Iberville...Livingston...lower
Jefferson...lower Lafourche...lower Plaquemines...lower St.
Bernard...lower Terrebonne...northern
Tangipahoa...Orleans...Pointe Coupee...southern
Tangipahoa...St. Charles...St. Helena...St. James...St.
John The Baptist...St. Tammany...upper Jefferson...upper
Lafourche...upper Plaquemines...upper St. Bernard...upper
Terrebonne...Washington...West Baton Rouge...and West
Feliciana.

GM...none.
MS...excessive heat watch from 11 am Sunday to midnight Monday for
the following zones:
Amite...Hancock...Harrison...Jackson...Pearl
River...Pike...Walthall...and Wilkinson.

GM...none.
&&

$$

24/rr
13/mh

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