441
FXUS64 KJAN 040249
AFDJAN

Area Forecast Discussion
National Weather Service Jackson MS
949 PM CDT Fri May 3 2024

...New MESOSCALE UPDATE...

.MESOSCALE UPDATE...
Issued at 949 PM CDT Fri May 3 2024

Rest of tonight...

Evening RAP analysis/GOES East water vapor imagery indicate
shortwave axis moving through the northeastern portions of the
region, with rain chances quickly dwindling. In the wake, there is
some descent & GOES East total precipitable water (PWs) indicate
some drying along the Gulf Coast & to the west. 00Z soundings,
especially at SHV, indicate drying in the 700-300mb layer, with
lowered mean RH`s in this layer progged to spread eastward. This
will continue to clear out cloudiness. With continued moist
southerly flow gradually decoupling, lows falling into the low-
mid 60s, crossover temps will reach nearly 3-6 degrees. This
pattern supports low stratus & dense fog developing after
midnight across the region. HREF probs >10-30% are widespread &
convective allowing models (CAMs) indicate potential for areas of
dense fog across the Gulf Coast region. There could be two zones
of concern for dense fog, northwest of the Natchez Trace & to the
southeast, with some decreased coverage along the Natchez Trace &
I-55 corridor. Decided to not get too specific & went ahead with
an areawide "Elevated" HWO graphic / Dense Fog advisory. The
advisory runs from just after midnight through 9AM Saturday.
Updates are out. /DC/

&&

.DISCUSSION...
Issued at 245 PM CDT Fri May 3 2024

Tonight through Sunday night...Isolated to scattered showers and
thunderstorms are occuring across much of the area this afternoon,
and this will continue before ending from west to east early this
evening. Skies may clear some overnight, and with good radiational
cooling patchy areas of dense fog will be possible early on
Saturday. An HWO graphic will be issued for this potential. Another
short wave will move into the area Saturday afternoon and this will
kick off another round of shower`s and storms. With a little better
lapse rate/instability on Saturday, a strong to possibly severe
storm cannot be ruled out Saturday afternoon. Little will change on
Sunday as moisture continues and yet another in a series of short
waves move across the area. Drier air begins to move into the area
Sunday night. Highs through the weekend will be in the 80s, with
overnight lows in the mid 60s./15/

Monday into Friday...the overall forecast for next week remains
similar. Focus will be well above normal/heat early into mid week,
potential for severe storms mainly in the Thu-Fri periods, then
followed by a marked cool down. The driver for the increasing warmth
will be with a pattern shift to more of a ridge influence with the
ridge axis over us Mon, then the ridge shifting eastward as we see a
powerful system dive across the Rockies and Central Plains. We will
be on the western periphery of the low level ridge/high and that
will provide a decent S/SW lower level flow to bring in moisture and
those well above normal lower level temps. Additionally, we will see
capping in play which will keep rain/storm chances more in check.
There`s some 20-30% type PoPs for Mon-Wed, but this is more due to
model variability and I expect this to lower some. The exception
could be in the far N, where more proximity to the better lift could
allow for better chances.

As for severe weather potential...this is mainly looking like
potential for a round or two sometime in the Thu/Fri periods. PoPs
have come in higher which fits and will follow. Look for chances to
continue to increase for a particular period as better timing starts
to work itself out. Like yesterday and prev guidance, uncertainty is
pretty decent on specifics and timing, which is often the case at
day 6-7. However, the pattern and consistency for the needed
ingredients (instability, steep lapse rates, moisture, shear, lift)
continue to show up. I`ll also add, later Wed night is a period to
watch as well as there will likely be severe activity on-going to
our NW/N which could migrate down into some of our northern area.
Lastly, the ingredients I noted are all reaching very solid levels
and fitting of a potentially upper end type event(s). Details will
determine the type of severe, but at this time, confidence is on
wind/hail.

In the wake of this system, the trends are for a solid front/trough
passage for the weekend which would bring much cooler conditions to
the area. /CME/

&&

.AVIATION...
(00Z TAFS)
Issued at 734 PM CDT Fri May 3 2024

Other than some light SHRA lingering at GTR/MEI, expect clearing
over the next hour. Expect a mixed bag of IFR-LIFR flight
categories overnight, with worst flight categorical restrictions
from low stratus & some dense fog across the area. Onset timing
looks to be around 04/07-09Z before lifting to VFR around
07/14-16Z. Light southerly sfc winds will persist the next 24
hours, sustained up to 10mph & brief higher gusts. Some SHRA & iso
TSRA are psbl Saturday aftn, but confidence is too low to
introduce in the 00Z TAF cycle. /DC/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       64  86  66  83 /  10  40  30  50
Meridian      63  88  65  87 /  20  40  30  40
Vicksburg     64  86  67  83 /  10  40  30  50
Hattiesburg   65  88  66  87 /   0  30  10  30
Natchez       64  86  65  81 /   0  40  30  50
Greenville    66  84  67  80 /  10  40  40  60
Greenwood     65  84  67  83 /  10  40  40  70

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...Dense Fog Advisory from 1 AM to 9 AM CDT Saturday for MSZ018-019-
     025>066-072>074.

LA...Dense Fog Advisory from 1 AM to 9 AM CDT Saturday for LAZ007>009-
     015-016-023>026.

AR...Dense Fog Advisory from 1 AM to 9 AM CDT Saturday for ARZ074-075.

&&

$$

DC/CME/DC