Area Forecast Discussion
Issued by NWS New Orleans/Baton Rouge, LA

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FXUS64 KLIX 200105

Area Forecast Discussion
National Weather Service New Orleans LA
805 PM CDT Mon Mar 19 2018

.SOUNDING DISCUSSION...Sounding was successful bursting at 6.4
mb. Nothing really interesting to talk about in this evenings
sounding. Biggest change from this morning was the continued
drying of the column which was mentioned in previous discussion.
PWS have now dropped down to 1.08. As for winds they have relaxed
a little in the upper levels but have picked up in the LL thanks
to the deepening of the sfc low which was sitting over the
TN/AL/MS border. /CAB/


.PREV DISCUSSION... /issued 410 PM CDT Mon Mar 19 2018/


Cold front over northeast to southwest Louisiana will continue to
push fairly quickly east through most of the forecast area the
remainder of this afternoon and this evening and through the
coastal waters overnight. Drier air has already filtered into the
forecast area ahead of the cold front, and this has capped off and
inhibited most of the convective development today. There is still
a slight chance of a stray shower and possibly a thunderstorm over
eastern areas through just before sunset in advance of the cold
front, but most locations should remain dry. The cooler and drier
air will surge in very noticeably tonight as surface high
pressure builds from the plains into the Mississippi Valley and an
upper level trough slides east towards the eastern seaboard. This
will lead to very pleasant conditions under clear skies despite
being below normal for temperatures Tuesday into Wednesday. Very
low humidity values down around 25 percent are expected during
peak heating on Wednesday, so naturally this will support some
cooler low temperatures in the low to mid 40s for the south
Mississippi and inland southeast Louisiana areas Tuesday and
Wednesday nights.


Northwest flow aloft and surface high pressure will keep the
forecast area dry on Thursday with moderating high temperatures
returning closer to the seasonal normals. Upper level troughs on
both the west and east coast regions will be gradually sliding
east which will allow the shortwave ridge to move over and east of
the forecast area Friday night through Saturday night. Southwest
flow will become more active in the southern stream out of Mexico
and Texas, so the next initial weak shortwave trough may bring our
next chance of showers about Monday, but it appears it should
be dry and warm this weekend. 22/TD


VFR conditions will prevail at all of the terminals through around
12z tomorrow.  An area of MVFR ceilings ranging between 2000 and
3000 feet could develop between 12z and 18z tomorrow at KMCB as a
thermal trough associated with an upper level low passes through the
Lower Mississippi Valley.  These low ceilings should begin to clear
after 18z tomorrow at KMCB. 32


A cold front will pass through the waters tonight.  A much colder
and drier airmass will advect in behind this front, and produce a
period of Small Craft Advisory conditions from late tonight through
Wednesday morning.  Conditions will quickly improve through the
afternoon hours on Wednesday as a strong surface ridge builds over
the Gulf South.  Winds should average around 10 knots and seas
should be 3 feet or less Thursday and Friday.  The high is expected
to shift toward the eastern Gulf by Saturday, and winds should
increase from the south to around 15 to 20 knots. 32

DSS code: Blue.
Deployed: None.
Activation: None.
Activities: Monitoring river flooding

Decision Support Services (DSS) Code Legend
Green  = No weather impacts that require action.
Blue   = Long-fused watch, warning, or advisory in effect or high
         visibility event.
Yellow = Heightened impacts with short-fused watch, warning or
         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 of severe and/or direct
         tropical threats; Events of National Significance.


MCB  49  64  42  67 /  10  10   0   0
BTR  51  66  44  69 /  10   0   0   0
ASD  55  68  43  69 /  10   0   0   0
MSY  57  68  50  68 /  10   0   0   0
GPT  57  67  45  68 /  10  10   0   0
PQL  58  68  42  69 /  10  10   0   0


GM...Small Craft Advisory from 4 AM Tuesday to 10 AM CDT Wednesday
     for GMZ532-536-538-550-552-555-557-570-572-575-577.

GM...Small Craft Advisory from 4 AM Tuesday to 10 AM CDT Wednesday
     for GMZ536-538-550-552-555-557-570-572-575-577.


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