Byram, Mississippi 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

324
FXUS64 KJAN 131203
AFDJAN

Area Forecast Discussion
National Weather Service Jackson MS
703 AM CDT Fri Jun 13 2025

...New AVIATION...

.DISCUSSION...
Issued at 428 AM CDT Fri Jun 13 2025

Through next Wednesday night...

Today and Tonight: Synoptic pattern consists of cutoff low lifting
into the Ozarks into northeast OK to the KS, MO and AR border. Moist
southerly return flow and deep tropical moisture (1.8-2.1 inches)
situated across the Gulf Coast region. Scattered to numerous rain
and storm coverage (55-85%) is anticipated by late morning and
persisting into the aftn to evening. Upper level jet dynamics and
southwesterly low-level jet is progged to lift northeast through the
day. Lapse rates will be limited and bulk shear in the 0-3km/0-6km
layer in the 20-25kt range. This should limit any concern with any
stronger convection to generally southeast of the Natchez Trace
corridor and into the I-59 to Hwy 45 corridors. With nearly 10-15kts
southwesterly bulk shear in the 0-2km layer, northeast propagating
convection orthogonal to the background wind flow could bring the
potential for gusty wind. Localized heavy downpours exceeding 2-3
inches remains a concern again, but boundary/mesoscale interactions
and forward propagation mitigate some of those concerns. WPC has
highlighted northern areas for a "Slight" risk of heavy rain/flooding
risk. However, prob match mean (PMMs) exceeding 3 inches remain
generally less than 10%, with exceeding 1 inch probs of 30-50%.
Exceeding flash flood guidance and 2-5 return interval probs remain
less than 20%, further supporting no mention in HWO graphics. Rain
and storm chances wind down before midnight across the heart of the
region, but isolated to scattered coverage (15-35%) will spread
southward into the I-20 corridor overnight. Sensible weather will
consist of seasonable highs (86-92F), some seasonably cool in the
Delta region, and seasonably warm lows, some 3-8F above (69-74F).

Saturday through next Thursday night: Upper cutoff low will somewhat
phase over the Mid South to TN Valley with the synoptic jet situated
well off to the north southern Canada, Hudson Bay, Newfoundland and
northern Atlantic. This will aid in summertime warmth and rain/storm
coverage. Numerous to widespread rain and storm coverage (65-90%)
will persist into the weekend Saturday but shifting focus further
eastward into late weekend. Low level flow will lighten and become
more westerly. Highs will be seasonable through the weekend (86-
93F), with seasonably warm lows, some 3-8F above (69-75F). High
humidity, combined with wet antecedent soils, will keep elevated
boundary layer moisture. Dewpoints should range from 74-79F, with
resultant aftn heat indices exceeding 102F daily. This summertime
heat and humidity will result in increased heat stress into the
weekend, especially along and south of I-20. Due to high rain/storm
coverage, holding off heat stress HWO graphics but may be needed
later.

The upper level low lifts northeast across the TN Valley to
Appalachians, westerly low level flow will support some continued
moist advection and deep moisture around 2 inches. Scattered to
numerous rain and storm coverage continue, with another shortwave
trough axis progged to swing across the Mid South to Gulf Coast
states into early to late next week. This increased ascent, combined
with deep tropical moisture and northwest flow, support continued
wet pattern. There are increasing trends in ensembles (GFS and Euro)
of longwave trough and frontal propagating across the Plains and
into the lower to mid MS Valleys around mid-late week. This may lead
to just enough low level flow to support some organized strong to
severe storms late next week. However, trough amplitude and timing
diverge in global guidance and ensembles. Will need to continue to
monitor this to see if trends persist. Muggy conditions worsen as
highs moderate to seasonably warm, some 2-5F above (88-92F Monday to
90-94F both Tuesday to Wednesday) while lows remain seasonably warm,
some 3-9F above (71-76F Monday and Tuesday while the warmest on
Wednesday morning). Combined with an uptick in boundary layer
moisture, heat stress will worsen into mid to late week (Wednesday
to Thursday). HWO heat graphics may be needed as we get closer. Make
sure to stay hydrated, wear comfortable and cool clothing and check
on family, neighbors and pets who may need cool places to stay
during hot afternoons and muggy nights. /DC/

&&

.AVIATION...
(12Z TAFS)
Issued at 659 AM CDT Fri Jun 13 2025

A mix of VFR/MVFR/IFR conditions prevail at TAF sites this
morning, but expect improvement to mostly VFR/MVFR conditions
later this morning into the afternoon hours. Scattered showers
and thunderstorms will continue this morning through much of the
day once again, which will bring occasional MVFR/IFR conditions
to sites into this evening. /15/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       89  72  89  73 /  80  40  80  30
Meridian      89  71  90  71 /  70  30  80  40
Vicksburg     88  72  90  74 /  80  30  70  30
Hattiesburg   91  74  93  74 /  60  20  80  30
Natchez       87  72  89  74 /  70  30  70  20
Greenville    86  72  86  73 /  60  50  80  40
Greenwood     87  72  87  73 /  80  60  90  40

&&

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

$$

/15