518
FXUS64 KJAN 190200 AAA
AFDJAN

Area Forecast Discussion...UPDATED
National Weather Service Jackson MS
900 PM CDT Wed Sep 18 2024

...New MESOSCALE UPDATE, AVIATION...

.MESOSCALE UPDATE...
Issued at 900 PM CDT Wed Sep 18 2024

Rest of tonight...

A quiet night is on tap. The Gulf Coast region remains in northwest
drying flow, with drier air analyzed in GOES East total precipitable
water (PWs) imagery & regional 00Z soundings (1.2-1.4 inches).
Sfc ridge of high pressure will keep light flow & favorable
radiational cooling environment around overnight. Lows will be
more seasonable north of I-20 (62-66F) & seasonably warm along &
south of I-20 (67-71F). With drier air mixing down into the low-
levels from the north, this should limit fog coverage to being
confined to low-lying, sheltered areas & river valleys. There is
a low to medium chance of patchy to localized areas of fog but
dense fog a low chance. Kept mention of fog. HREF probs remain
too low (<30%) & confined to extreme southern corridors of Hwy 84
to Hwy 98 corridors for any mention of dense fog in the HWO.
Updates are out. /DC/

&&

.DISCUSSION...
Issued at 203 PM CDT Wed Sep 18 2024

Tonight through Tomorrow Night

The main challenge will onset, coverage, and thickness of low-
lying stratus and fog development throughout the CWA. That being
said we`ve had some dry air mix into the area mostly off to the
northeastern most quadrant, which should inhibit any low-lying
stratus development in that area. The rest of the CWA will see
areas of patchy fog with denser development in low elevation sites
along shallow river valleys. In any event, hydrometeors are
expected to burn off by mid morning across all sites.

Other weather parameters look to be typical, following with
diurnal trends. Highest wind speeds look to be under 10kts and
generally northerly, although the direction may be variant with
light winds and a ridge that extends from the surface through to
300mb that is slowly building throughout the period. Precipitation
chances remain near 0% with the isentropic lift mechanism eroding
away early this morning, being relegated along the MS/AL/FL gulf
coast. Lows in the mid 60s and highs are expected to be the high
80s.

Friday through Tuesday...

Ridging will continue to entrench itself across the Lower
Mississippi River Valley and as the cut-off low over the Carolinas
(the remnants from an unnamed tropical system that moved through
earlier this week) begins to fill and push eastward; we will see a
shifting of the ridge axis to a more positive tilt. This will
result in tame conditions across the region for the remainder of
the period, with rain chances rebounding into the 20% range
Wednesday afternoon as the ridge completes its traversal across
our area and a trough beginning to meander over from the west.
Relative humidity values are not expected to change much so expect
a more narrow diurnal swing in our temperatures: Highs in the mid
to high 80s and lows in the low to mid 60s./OAJ/

&&

.AVIATION...
(00Z TAFS)
Issued at 835 PM CDT Wed Sep 18 2024

VFR conditions will predominate through the TAF period. Brief
localized fog & low stratus cannot be ruled out early Thursday
morning, but confidence at any specific site is too low to include
in TAF in the 00Z TAF cycle. Any localized flight restrictions
that develop will lift mid-morning after 19/15-16Z Thursday. Winds
will be near calm tonight & northerly Thursday, generally less
than 10mph. /DC/DL/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       68  90  67  90 /   0   0   0   0
Meridian      65  91  67  92 /   0   0   0   0
Vicksburg     69  91  66  91 /   0   0   0   0
Hattiesburg   71  92  69  94 /   0   0   0   0
Natchez       70  90  67  91 /   0   0   0   0
Greenville    64  88  65  90 /   0   0   0   0
Greenwood     64  90  67  92 /   0   0   0   0

&&

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

$$

DC/OAJ/DL