418
FXUS64 KJAN 201940
AFDJAN

Area Forecast Discussion
National Weather Service Jackson MS
240 PM CDT Thu Jun 20 2024

...New DISCUSSION...

.DISCUSSION...
Issued at 240 PM CDT Thu Jun 20 2024

Tonight and Tomorrow...

Hi-res global guidance continues to highlight high pressure sfc
ridging across much of the southeast CONUS. This will help keep
weather conditions generally quiet across central MS tonight.
Easterly flow will continue to push a weak shortwave, located on the
southern peripheral of the sfc high, which could bring some low PoPs
(around 11%), mainly for areas along and southeast of the I-59
corridor. The higher rain chances will remain along the southern
Gulf coast as guidance shows Tropical Storm Alberto moving westward
across central Mexico. We can expect to see some cloud coverage
especially for areas along and west of the I-55 corridor heading
into the overnight period. Expect overnight lows to drop into the
low 70s areawide. Dry/quiet conditions are expected tomorrow for most
of the area as high pressure ridging continues to push the drier
airmass across the southeast CONUS. A few popup showers or an
isolated storm can`t be ruled out, especially further southwest
portions of the area where somewhat greater moisture exists. Expect
afternoon highs to peak into the mid 90s across the forecast area.

Friday Night through Thursday...

The combination of high pressure ridging and a persistent dry
airmass will keep our weather relatively dry through the end of this
week. Within this regime, afternoon temperatures will gradually
increase into the upper 90s to near 100 by Sunday. Around this
timeframe, low-level flow will begin to shift to the south and
moisture will begin to return to the area, with dewpoints climbing
into the low 70s. This will begin to yield heat indices in the
triple digits in many areas. Went ahead and made a few modifications
to the heat graphic for Sunday. The limited risk has been expanded
further east to cover the Golden Triangle. Heading into the next
work week, mid/upper ridging will begin to break down and shrink
westward, resulting in a more perturbed NW upper flow pattern as
future global guidance highlights a 1012 mb sfc high slowly moving
eastward across the Ohio River Valley.

Rain chances will start to increase starting on Monday as deep layer
moisture continues to increase across the area. Hot conditions will
persist given the increased moisture allowing for heat indices to
reach critical thresholds. Given the warming trends, adjustments
have been made to the heat graphic for Monday and Tuesday. The
Elevated heat risk has be expanded further east to cover our entire
forecast area. Heading into Wednesday-Thursday, the precip coverage
will have a big impact on the afternoon highs. Although heat indices
around this timeframe are around critical threshold, forecast
confidence is low at this point regarding how the precip coverage
will impact the heat potential. We will continue to monitor trends
will provide updates to the heat potential for Wednesday as we get
closer and forecast confidence increases.

In addition to this, NHC is monitoring an area of potential
development in the southwest Atlantic, just off the coast of the
southeast US. At the moment, none of this activity is expected to
have an impact on our weather through the extended period. We will
continue to closely monitor this area of development and will
provide updates as trends start to increase. /CR/

&&

.AVIATION...
(18Z TAFS)
Issued at 144 PM CDT Thu Jun 20 2024

VFR conditions with easterly winds around 5-10 kts should prevail
at the TAF sites through the period. /NF/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       71  94  71  95 /   0   0   0   0
Meridian      69  94  69  97 /  10   0   0  10
Vicksburg     71  94  72  95 /   0   0   0   0
Hattiesburg   72  94  70  97 /  10   0   0  10
Natchez       70  92  71  95 /   0  10   0   0
Greenville    72  96  73  97 /   0   0   0   0
Greenwood     71  95  72  97 /   0   0   0   0

&&

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

$$

CR/NF/CR