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Area forecast discussion
National Weather Service New Orleans la
422 am CDT Fri may 26 2017

Short term...
the nice weather will begin its transition to the warm muggy
conditions again by this evening. A cold front will slowly move
into the area and stall near the coast by late Monday and remain
into Thursday before lifting back to the northeast. Best support
while the frontal boundary is in the area will be Sunday through
Monday night. Sunday will begin a daily sea breeze. And Monday
this sea breeze will begin to interact with the stalling frontal
boundary. This will aid moderate severe weather variables for
Sunday and Monday. Although a severe thunderstorm would be
a possibility Sunday, there will be more activity around Monday
providing a slightly better chance. This does not look widespread
but a few individual cells could reach the severe threshold.
Tuesday through Thursday should be more of a normal Summer pattern
for the area as scattered sh/ts should be capable of developing
each day with the help of the stalled sfc trough, sea breeze and
daytime heating.

Long term...
Friday is also where global suites are beginning to advertise a
strong inverted tropical wave developing from the Bay of Campeche
toward the Texas coastal Bend with a very deep fetch of moisture
connected to the Pacific. The Pacific is where this feature is
expected to come from as well. This system is currently at about
10.0n 87.0w or roughly 140 miles west of Costa Rica. Models are
bringing this trough to the Gulf of Tehuantepec before stalling it
Sunday through Wednesday. The northern end of the trough then
becomes more active over the Bay of Campeche Thursday of next
week. Variables conducive for tropical development are not very
strong as this feature develops northward. But that would not
normally be the focus for a weak feature with tropical origins in
June. It is not abnormal to see a weak barotropic system move
through the Gulf in June and the main issue with these are
normally very heavy rainfall for someone. The only issue at this
point is that this is the first time models have initiated this.
We would like to see several successive model runs produce this
before showing it as relevant to the extended fcast. But it is
still a possibility as we move into the start of the tropical



VFR conditions will persist at all of the terminals through 06z.
After 06z, some MVFR and IFR restrictions may develop as a low
stratus deck forms below an elevated inversion. 32



Little change in thinking from the previous forecast. A broad ridge
of high pressure will remain over Florida and the eastern Gomex
through the middle of next week. This will keep a general onshore
wind of 10 to 15 knots in place through the period in the open. Gulf
waters. Seas of 1 to 3 feet are also expected through Wednesday. In
the sounds and tidal lakes, a weak front will stall and dissipate
along the Louisiana and Mississippi coastline on Monday night into
Tuesday. Winds should decrease to around 5 knots or less and turn
more variable with the dissipating front in the area. Waves will
generally remain 2 feet or less through the entire period. 32


Decision support...
Activities...monitoring Mississippi River flooding

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


Preliminary point temps/pops...
mcb 89 70 90 73 / 0 10 10 10
btr 89 72 91 75 / 0 0 10 10
asd 87 73 90 76 / 0 0 10 10
msy 87 74 89 76 / 0 0 10 10
gpt 84 74 85 77 / 0 10 10 10
pql 85 70 87 73 / 0 0 10 10


Lix watches/warnings/advisories...

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