589
FXUS64 KJAN 310059 AAA
AFDJAN

Area Forecast Discussion...UPDATED
National Weather Service Jackson MS
759 PM CDT Thu Jul 30 2026

...New MESOSCALE UPDATE, AVIATION...

.KEY MESSAGES...

- Heat stress will continue to be a concern over much of the area
  today and Friday.

&&

.MESOSCALE UPDATE...
Issued at 759 PM CDT Thu Jul 30 2026

Rest of this evening into tonight...

The region remains on the eastern periphery of deep anticyclone
ridge centered near west TX and southern AZ and large scale
troughing along the Atlantic seaboard and East Coast. This has
driven a stationary frontal boundary centered across the
Interstate 20 corridor. With continued compression south of the
front and thermal warmth, dangerous heat has continued into the
current hour. The previous heat advisory just expired at the top
of the hour but heat concerns will persist the next couple of
hours. With deep moisture (2.2 to 2.5 inch PWs) centered along the
stationary front, scattered to numerous showers and storms have
developed today. Northwest flow has driven in a few shortwaves
that, combined with frontal convergence, helped sparked the
convective coverage today. Mid level lapse rates were not too
high (vertical totals around 23C) but low level lapse rates and
high boundary layer dewpoints in the mid to upper 70s was driving
high SBCAPE/MLCAPE (around 3500 to 5000 J/kg). This was helping
some stronger storms at times with locally heavy rain as well.
This convection will wind down over the next couple of hours at
most. There will not be much relief overnight with seasonable
warmth, some 4F to 6F above (73F to 76F). Updates are out. /DC/

&&

.DISCUSSION...
Issued at 147 PM CDT Thu Jul 30 2026

Through Friday: Unfortunately, the relief from the dangerous heat
stress has been delayed some, and a heat advisory has been
extended through Friday and now includes the entire area. The
oppressive heat has maintained today over most of the area as
boundary layer humidity is peaking at the worst time in
association with moisture pooling associated with a weak surface
boundary over our area. High dewpoints combined with temperatures
rising well into the 90s is sending heat index values to around
110, but will say that scattered convective precipitation will
hopefully help to reduce some of the heat, or at least keeping it
from reaching more dangerous levels, as we go through the
remainder of the afternoon. Expect a general repeat of today`s
weather for Friday with fairly high coverage of diurnally driven
convection, and have maintained the elevated heat threat graphic.
/EC/

Saturday Onwards: The long-term forecast remains on track.
Increased chances for convective activity and cloud coverage will
take hold due to the surface confluence from the aforementioned
front, which could provide a few degree dip, thus mitigating heat
threat concerns. With upper flow becoming more northerly and
northwesterly during this time frame, we will see the potential
for one or two convective complexes moving into the area or
developing over the area. This will result in continued higher
diurnal rain chances heading into the weekend. Going into early
next week, conditions become less favorable for convective
coverage. In terms of sensible weather, we`ll see rain chances
diminish and heat potentially rebuild some, but it should remain
below what we`ve seen over the last few days. /OAJ/EC/

&&

.AVIATION...
(00Z TAFS)
Issued at 759 PM CDT Thu Jul 30 2026

VFR conditions exist at all TAF sites, but the occasional SHRA or
TSRA could restrict visibility and bring brief gusts in excess of
30 to 40mph at times. Convection should wind down around 31/02Z
at most, with quiet overnight period. Winds will weaken and
become light and variable, with some clouds overnight. The only
exception could be near MEI where the occasional lowered stratus
cannot be ruled out overnight. However, not confident to put
actual restrictions in the 00Z TAF cycle. Light westerly wind,
with occasional gusts higher than 10 to 15mph, will be the norm
into Friday afternoon. SHRA and TSRA potential peak again
tomorrow afternoon, generally after 31/19 through the end of the
TAF period. /DC/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       75  93  75  93 /  20  60  20  20
Meridian      74  91  74  91 /  40  70  40  50
Vicksburg     75  94  76  93 /  10  40  20  20
Hattiesburg   76  91  75  92 /  20  50  20  30
Natchez       75  95  75  94 /  10  10  10  10
Greenville    75  95  76  94 /  20  40  40  30
Greenwood     74  93  75  93 /  10  60  40  30

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...Heat Advisory from 10 AM to 7 PM CDT Friday for MSZ018-019-
     025>066-072>074.

LA...Heat Advisory from 10 AM to 7 PM CDT Friday for LAZ007>009-015-
     016-023>026.

AR...Heat Advisory from 10 AM to 7 PM CDT Friday for ARZ074-075.

&&

$$

DC/DC