771
FXUS64 KJAN 161744
AFDJAN

Area Forecast Discussion
National Weather Service Jackson MS
1244 PM CDT Tue Jul 16 2024

...New AVIATION...

.MESOSCALE UPDATE...
Issued at 954 AM CDT Tue Jul 16 2024

Morning WV imagery show a narrow mid/upper trough axis extending
from SW to NE over the area and continues to cut off in the upper
levels around east TX/west LA. The rest of the morning will be
relatively quiet as 12Z morning sounding observations show limited
moisture in the low levels, with a strong capped environment near
the mid levels (especially near 700mb). The main bulk of convection
today will hold off until later this afternoon with the best
rain/storm chances (around 35%) across E/SE portions of MS. Cloud
cover will be generally clear mainly for areas west of I-55.
Meanwhile, areas east of I-55 will start to see some mid-high clouds
later this afternoon. Daytime temperatures will peak in the upper
90s across our forecast area with heat indices between 105-110
degrees. A Heat Advisory remains in effect for the entire area until
8 PM this evening for our entire forecast area including portions of
southeast Arkansas, and all of our northeast Louisiana parishes.
/CR/

&&

.DISCUSSION...
Issued at 354 AM CDT Tue Jul 16 2024

Through tonight: For the near term, we will remain locked in a
familiar pattern from the past few days. A narrow shortwave
mid/upper trough axis, evident in current WV imagery, still
extends from SW to NE over the area and is beginning to cut off in
the upper levels around east TX/west LA. Ahead of these features,
there continues to be a seasonably moist airmass over much of the
area. We are beginning the morning with festering isolated
showers and TS across parts of central and east MS which are being
instigated by this feature. However, once again the bulk of
convection today will hold off until maximum heating this
afternoon, lingering into the early evening as instability slowly
wanes. As has been seen in recent days, there will be some
potential for a stronger storm or two given the abundance of
instability, but the threat is limited enough to not highlight
with a formal severe weather outlook at this time. Meanwhile, heat
stress continues to be the primary concern, with heat indices
likely to rise into the 105-110F range again today. A Heat
Advisory remains in effect for the entire area. /DL/

Wednesday through next Tuesday...

Wednesday will spark the beginning of a pattern change across the
region, with a low level ridge maximizing across the southeast
CONUS ahead of an upper trough expected to extend southwards into
the Middle/Lower Mississippi Valley. Increased heights and
westerly flow will prompt dangerous heat conditions across the
region, with highs in the upper 90s and lows in the lower to
middle 70s on Wednesday. heat indices are expected to climb into
the triple digits, with some areas having the potential to exceed
110 degrees. Expect a Heat Advisory as an "Elevated" Risk for
dangerous heat stress is being advertised. By Thursday, the ridge
will break down as a broad trough dips southwards, bring increased
potentials for scattered to numerous showers and storms, along
with more seasonable temperatures through the weekend. PWATS will
be abnormally high along the coast, with values exceeding 2.5
inches at times. The potential for flash flooding will continue to
be monitored for this weekend.

By Sunday into the new work week, low level ridging will begin to
build in from the southeast, which will allow temperatures to
begin to increase into the work week. Highs will range in the
lower to middle 90s through Monday, with heat indices reaching up
to 105 for areas in the southern portions of the CWA. Rain chances
will remain scattered to numerous, as a frontal boundary hangs up
near the Gulf Coast and looks to keep a fairly moist, tropical-
like layer across the south through Tuesday. /AJ/

&&

.AVIATION...
(18Z TAFS)
Issued at 1244 PM CDT Tue Jul 16 2024

VFR ceilings and conditions will prevail across all TAF sites to
start off the period. SHRA and -TSRA will be possible across east
and southeast MS starting around 20Z Tuesday and will last through
02Z Wednesday, which could lead to a few TAF sites (mainly MEI) with
sub-VFR conditions. Rain chances will begin to diminish by 02Z
Wednesday with quiet conditions expected through the overnight
period. Scattered SHRA and TS with brief wind gusts will be possible
18Z Wednesday especially across east and southeast MS. /CR/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       76  97  75  92 /  10  50  40  90
Meridian      74  97  73  93 /  20  60  40  90
Vicksburg     76  97  74  91 /  10  20  30  80
Hattiesburg   76  97  76  94 /  30  60  20  90
Natchez       75  95  75  92 /  10  30  20  80
Greenville    77  97  73  86 /   0  30  50  70
Greenwood     76  97  73  88 /   0  40  60  80

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...Heat Advisory until 8 PM CDT this evening for MSZ018-019-025>066-
     072>074.

LA...Heat Advisory until 8 PM CDT this evening for LAZ007>009-015-016-
     023>026.

AR...Heat Advisory until 8 PM CDT this evening for ARZ074-075.

&&

$$

DL/AJ/CR