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Area forecast discussion 
National Weather Service New Orleans la
645 PM CST Wednesday Nov 25 2015

..sounding discussion...

Moisture is up again in the sounding this evening as stronger
onshore flow is in place... precipitable water is at 0.99 inches. Isolated
showers will occasionally be a possibility in this maritime
layer. Winds are east southeast from the surface to 800 mb then from
the south in an inversion layer to 700 mb. The air is much drier
still above the inversion and winds are northwest aloft. Peak wind
is 105 kts at 180 mb.



Previous discussion... /issued 252 PM CST Wednesday Nov 25 2015/


High pressure centered off the Maine coast is exerting its
influence over the eastern half of the country this afternoon. Low
pressure over southwest Ontario has a cold front extending
southwestward into northeast New Mexico. An upper low was centered
near Reno Nevada early this afternoon.

Across the local area...skies have been partly sunny with east-
southeast winds. Temperatures have warmed nicely with temperatures
in the lower and middle 70s...and dew points around 60...which is
unseasonably warm for late November.

Short term...

The upper low will not make a lot of eastward progress through
Saturday...remaining over the Great Basin area. The current
frontal system over the Great Plains will only move very slowly
eastward as it weakens. The front by Saturday morning is likely to
extend from Pennsylvania to near Shreveport into Texas.

With the persistent east to southeast flow in place over the
area...we could see a few showers like occurred this morning
moving in from the Gulf...but much of the area should remain dry
through Saturday. Temperatures should continue to be 5-10 degrees
above normal through Saturday...and will trend toward the middle
to warmer end of the guidance.

The persistent easterly flow will continue to enhance tide heights
through the next 36 to 48 hours. Tides are running 1 to 2 feet
above normal...and with relatively large tidal ranges the next two
cycles...will leave the coastal Flood Advisory in place. Per
coordination with the midnight shift...they will extend the
advisory through tomorrow night once we pass tonights high tide
cycle. 35

Long term...

Frontal system will continue to ooze its way eastward Sunday into
Monday. GFS and European model (ecmwf) solutions are now pushing the front into the
area on Monday. Any eastward progress will be rather slow...and
will be leaving some mention of precipitation in the forecast
through midweek. Temperatures Sunday and Monday will remain well
above normal ahead of the front. With somewhat better agreement on
frontal movement in the medium range...will accept the cooling
trend shown by guidance...but will not go quite as low as the
European model (ecmwf) numbers are showing. 35


Expect VFR to MVFR conditions to prevail through the taf period at
all terminals. Expect VFR through the evening as ceilings begin to drop
tonight and into tomorrow. Expect mostly MVFR conditions for
tomorrow. 13/mh


The coastal Flood Advisory continues as persistent easterly flow
should increase The Tides and swells and should cause some minor
nuisance coastal flooding impacts this through Thursday. High
pressure over the Atlantic coast line will be slow to move. Still
maintaining current forecast but have elected to issue exercise
caution for Lake Pontchartrain. A cold front will progress
southeastward and stall near Texarkana Friday. As this occurs...a
strong pressure gradient will build over the southern US and Gulf
coastal waters. Easterly winds will remain elevated through the
week then shifting to southeast into the weekend. The cold front
may make it through the area by next week. 13/mh

Decision support...

Activities...coastal Flood Advisory tonight.
Small Craft Advisory through Thursday.
Monitoring minor flooding along Pearl River.

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 58 73 59 74 / 10 10 10 10
btr 62 76 62 78 / 10 10 10 10
asd 60 73 59 74 / 10 10 10 10
msy 65 73 63 77 / 10 20 10 10
gpt 59 70 57 72 / 10 10 10 10
pql 59 72 58 74 / 10 10 10 10


Lix watches/warnings/advisories...
la...coastal Flood Advisory until 6 am CST Thursday for laz040-050-

GM...Small Craft Advisory until 6 PM CST Thursday for gmz532-534-536-

MS...coastal Flood Advisory until 6 am CST Thursday for msz080>082.

GM...Small Craft Advisory until 6 PM CST Thursday for gmz534-536-538-



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