021
FXUS64 KJAN 140916
AFDJAN

Area Forecast Discussion
National Weather Service Jackson MS
416 AM CDT Tue May 14 2024

...New DISCUSSION...

.DISCUSSION...
Issued at 415 AM CDT Tue May 14 2024

Today and Tonight:

The bulk of the precipitation has move north and east of the area
this morning, but a few isolated showers will continue to be
possible through the morning. The main upper trough axis will move
across the area today and this may kick of isolated to scattered
showers/storms mainly for the northern and eastern portions of the
area. WIth limited moisture/instability expect any storms that do
develop this morning into the afternoon hours to remain below
strong/severe limits. Drier air will build in this afternoon and
expect the activity to move east of the area later this afternoon
and evening along with clearing skies. Skies will be mostly clear
overnight, with lows in the low 60s. /15/

Wednesday through Monday:

A split flow pattern will continue across the CONUS through next
weekend. Shortwave ridging over the Gulf Coast will prevail through
the day Wednesday and into Wednesday night, allowing for temps to
rebound into the mid and upper 80s Wednesday afternoon. Then
Thursday into Friday, model guidance indicate that a strengthening
southern stream jet and positively-tilted shortwave trough shift
eastward across the Southern CONUS. Increasing lift and instability
in advance of this system will increase the possibility for
organized severe thunderstorms in the Thursday-Friday window.
ECMWF/CMC solutions generate convection over East Texas Thursday and
steers a likely MCS toward central LA/MS Thursday night as well as
re-development closer to the central Gulf Coast Friday evening
overnight. Meanwhile the GFS/NAM solutions are less robust with
Thursday`s East Texas convection escaping the Plains and hold off
until Friday before brining more intense convection into our
forecast area. If the storms hold off in our area until Friday,
instability will have a greater chance to build northward in advance
of the system. GFS paints 1500-2000 J/kg of MLCAPE across the
southern tier of our forecast area by Noon on Friday with 50-60 kts
of westerly deep-layer shear across the area. These conditions would
certainly support organized severe thunderstorms across portions of
our forecast area.

The big *BUT* that must be emphasized is that with these southern
stream waves exciting storms upstream over the Southern Plains, it
has occurred several times recently that sheared storms to our west
have the chance to spread farther east and faster if an organized
MCS can develop. Therefore will highlight the Thursday evening into
Friday period as our next chance for severe storms. SPC has
introduced a Marginal Risk for severe storm to our southwest before
12Z Friday and Slight Risk (15% area) for central/northeast LA and
central/southern MS after 12Z Friday. To not get overly specific
with timing yet, will combine this threat into one graphic for the
previously-mentioned time range and leave further refinement to the
next few updates as the details of the wave come into better focus.
In addition to the threat of severe thunderstorms, the strong shear
and instability will be paired with increasing humidity in the
region. Latest guidance pushes PWAT values into the 1.7-2.0 inches
range by Friday, leading to a threat for heavy rain with storms.
Localized flash flooding could be a concern, especially for parts of
our area that have seen the most rain in the last week or two.
Current FLASH soil moisture values are most saturated from around
Richland and Madison parishes southeast to Clarke and Wayne
counties. A quick 2-3 inches of rain over any of those areas could
easily lead to ponding water or flash flooding. A Limited threat
area for Flash Flooding has therefore been introduced for Thursday
and Friday as well.

The upper-level trough axis should be clearing east of our forecast
area by Saturday night, so trended POPs lower than guidance Saturday
night and Sunday based on latest trends in deterministic guidance.
Peaking ahead into next week, the flow looks to become better phased
across the CONUS as a trough deepens over the western CONUS and a
ridge amplifies over Mexico and the western Gulf Coast region. The
likelihood of high temps reaching the lower 90s increases to start
the new work week, with average temps expected to be 5-10 degrees
above normal for much of the area. /NF/

&&

.AVIATION...
(06Z TAFS)
Issued at 1249 AM CDT Tue May 14 2024

A mix of VFR/MVFR/IFR conditions prevail across sites this evening
as the bulk of the precipitation exits the area. Expect mostly
MVFR/IFR conditions through the remainder of the night. Drier air
will build in on Tuesday with most sites becoming VFR after
16-17Z and continuing through the end of the period./15/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       82  61  85  63 /  10   0   0   0
Meridian      83  61  86  61 /  30   0   0   0
Vicksburg     83  60  86  64 /  10   0   0   0
Hattiesburg   86  63  88  64 /  30   0   0   0
Natchez       83  60  86  64 /   0   0   0   0
Greenville    81  63  85  65 /  20   0   0   0
Greenwood     81  62  84  64 /  30  10   0   0

&&

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

$$

15/NF/15