996
FXUS64 KJAN 171742 AAB
AFDJAN

Area Forecast Discussion...UPDATED
National Weather Service Jackson MS
1242 PM CDT Tue Sep 17 2024

...New AVIATION...

.MESOSCALE UPDATE...
Issued at 1002 AM CDT Tue Sep 17 2024

The forecast remains on track today with our early morning fog
burning off throughout the CWA and showers expected to develop
across the southern half of the forecast area today. The primary
driving mechanism for the weather today has transitioned from
Francine remnants to the interaction between a continental ridge and
a deep retrograding low centered over the eastern parts of the
Carolinas. This pattern has created easterly flow in SFC-700mb level
which will dry out the northern half of the CWA, inhibiting our rain
chances in those areas. Conversely, the offshore stationary boundary
to our south will allow for a moderate amount of isentropic lift,
coupled with high amounts of surface level moisture from previous
rainfall totals, will provide enough of the necessary ingredients
for light showers south of I-20 today. Nothing to get too excited
about though as projected totals for today are not expected to
exceed 0.10 inches.

High relative humidity values and moderate cloud coverage are
contributing to our smaller diurnal temperature swings, leading to
cooler highs in the mid 80s F and seasonable lows in the mid 60s F.
Winds are not expected to be particularly notable with generally
calm easterly conditions persisting throughout today./OAJ/

&&

.DISCUSSION...
Issued at 340 AM CDT Tue Sep 17 2024

Today and Tonight...

Overall the forecast for the short term period remains on track
with no major adjustment made. HREF model guidance is starting to
pick up on some early morning fog potential mainly across the
Golden Triangle and southwest portions of the area. Early morning
hi-res guidance continues to show a stalled frontal boundary
along the Gulf Coast. This combined with the presence of leftover
tropical moisture will allow for afternoon/early evening scattered
showers and storms generally for areas along and south of I-20.
Forecast confidence is much higher today given that the latest
GFS/NAM continues to hold onto rain chances through late Tuesday
afternoon. The presence of cloud cover combined with scattered
storms will help keep afternoon highs in the upper 80s across our
CWA. Later this evening, rain chances will begin to diminish
leading to quiet conditions across our forecast area with
overnight lows dropping into the mid 60s. With that being said,
continued saturated soil conditions along with stable overnight
conditions will help heighten widespread fog development heading
into the overnight period. Conditions will continued to be
evaluated for any potential dense fog advisories as we get closer
to early Wednesday morning. /CR/

Wednesday through Monday: With the exception of Wednesday afternoon
where there will be low chances of afternoon showers in our south,
dry weather is expected through Monday. Our normal lows run in the
lower 60s while our normal highs run in the mid 80s. Much of the
forecast period will see above normal morning lows and afternoon
highs.

Come Wednesday morning our CWA will still be on the back side of an
upper level trough with a weak center of high pressure to our north.
A stalled frontal boundary will be just to the south of our
southeast most zones. The surface high will remain in place but the
upper level trough will shift east through the day with shortwave
ridging aloft moving over our CWA. Model consensus develops a few
showers during the heat of the day and spreads the activity into our
southern zones. This convection is expected to dissipate by early
evening. With the shortwave ridge axis and the surface ridge across
our CWA Thursday, temperatures will top out a degree or two warmer
and convection will be inhibited. The ridging surface and aloft will
change its orientation across our region but remain dominant through
Monday. /22/

&&

.AVIATION...
(18Z TAFS)
Issued at 1237 PM CDT Tue Sep 17 2024

Morning low clouds and vis restrictions are improving, but we`re
still seeing some MVFR conditions hold for a bit longer. The
afternoon will be main VFR and only issues will be with areas
across the south half that could see some Iso/Sct showers. Evening
will be clear and focus will shift to fog potential. Guidance
seems bearish, but with solid rad cooling conditions and wet
ground and moist low levels fits with good conditions for fog to
develop. Due to this, will be having MVFR/IFR vis conditions
between 09-14z. Conditions could get worse and be more widespread,
so that`s something to watch. VFR conditions for Wed after 14z.
/CME/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       68  88  66  88 /   0   0   0   0
Meridian      64  89  64  90 /   0   0   0   0
Vicksburg     68  88  66  89 /   0   0   0   0
Hattiesburg   70  90  69  91 /  10  10   0   0
Natchez       69  88  68  89 /   0  10   0   0
Greenville    64  86  63  87 /   0   0   0   0
Greenwood     65  88  64  89 /   0   0   0   0

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...None.
LA...None.
AR...None.
&&

$$

OAJ/CME/