557
FXUS64 KJAN 061135
AFDJAN

Area Forecast Discussion
National Weather Service Jackson MS
635 AM CDT Sat Jul 6 2024

...New AVIATION...

.DISCUSSION...
Issued at 428 AM CDT Sat Jul 6 2024

Today through tonight: The most impactful weather, including
thunderstorm potential and the risk for dangerous heat, will
generally be for locations along/south of the I-20 corridor as we
begin the weekend. A weak west-to-east oriented frontal boundary
will meander over the forecast area this weekend, and the hottest
and most humid conditions should generally exist along and south
of the boundary, where we expect the development of numerous
showers and storms this afternoon. Poor lapse rates will continue
to limit updraft/storm intensity, but very moist air with
precipitable water (PW) up to 2.4 inches and H850 dewpoints up to
16 deg C will support very efficient and locally heavy rainfall
if slow-moving storms become focused. As we go into the evening,
storms should diminish quickly and then mostly quiet and humid
conditions are expected for the overnight. /EC/

Sunday through Friday night:

To begin the forecast period, very moist tropical airmass will
continue to flow into the area around weakening high pressure
stationed over the southeastern states. The increase in tropical
flow will combat the drier air associated with the stalled
boundary in the northern portions of the CWA throughout the day
eventually pushing the front northward out of the area. With this
moist tropical airmass, we can expect to see surface dewpoints in
the mid to upper 70s and PWs in the 2 to 2.5 inch range. This
tropical airmass will help maintain areawide rain chances
throughout the day with the greatest chances being in the
southeast. Increasing cloud cover and convection will likely limit
daytime temps Sunday for a majority of the CWA, however the
southern portions of the CWA will have the opportunity for some
early heating allowing for heat indices to approach dangerous heat
criteria. Thus the limited heat stress HWO graphic will remain in
effect for Sunday.

Going into next week: Upper level troughing will continue its track
eastward through the central states into the mid MS valley on
Monday. Southwesterly flow will persist allowing for continuous deep
layer moisture to flow into the area keeping scattered to isolated
diurnal convection constant each day of the period. By Tuesday we
will see increasing chances for showers and storms along the western
edges of the CWA as TC Beryl continues its track. NHC guidance
now show the cyclone turn more to the northeast across eastern
Texas as it weakens to a depression. This track will help to
increase rain chances Tuesday and Wednesday for our area,
especially over the ArkLaMiss Delta region where there could end
up being a risk for heavy rainfall. As we go through the
remainder of the week, we can expect diurnally driven rain and
storm chances to continue through end of the period. /KP/

&&

.AVIATION...
(12Z TAFS)
Issued at 631 AM CDT Sat Jul 6 2024

A considerable amount of IFR/LIFR category stratus/br/fg will
continue until about mid morning, then expect quickly improving
conditions during the late morning. Scattered SHRA/TS will be most
prominent during the afternoon to early evening for the southern
half of the area. Otherwise, VFR conditions and light surface wind
will prevail this afternoon and evening. Another round of low
stratus seems inevitable for early Sunday morning. /EC/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       90  74  91  75 /  60  30  50  20
Meridian      92  73  93  73 /  60  30  60  30
Vicksburg     90  74  90  75 /  50  10  40  20
Hattiesburg   93  76  94  76 /  70  50  70  20
Natchez       88  74  90  74 /  70  30  50  20
Greenville    92  73  91  75 /  10  10  20  20
Greenwood     93  74  91  75 /  10  10  20  20

&&

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

$$

EC/KP/EC