-- Discussion containing changed information from previous version are highlighted. --
791
FXUS64 KJAN 230521 AAC
AFDJAN

Area Forecast Discussion...UPDATED
National Weather Service Jackson MS
1221 AM CDT Sun Jun 23 2024

...New AVIATION...

.MESOSCALE UPDATE...
Issued at 944 PM CDT Sat Jun 22 2024

All is generally on track for the near term forecast and no
significant changes were made in this evening`s update. /EC/

&&

.DISCUSSION...
Issued at 208 PM CDT Sat Jun 22 2024

Tonight and Tomorrow...

Quiet conditions will continue heading into tonight as global
guidance continues to highlight strong mid/upper ridging across our
forecast area. Aside from few high clouds, skies will be generally
clear heading into the overnight period. The clear conditions will
allow for radiational cooling to occur allowing for nighttime
temperatures to drop into the mid 70s areawide. Hot weather
conditions will continue heading into tomorrow as the sfc high
starts to slowly shift east out of our CWA. Although the area will
remain on the eastern periphery of strong mid/upper ridging, low
level flow will become more southerly, with increasing low level
moisture beginning Sunday afternoon. Around this timeframe dewpoints
will reach in the 70s with temperatures in the upper 90s to near
100. This will yield heat indices approaching 105 F - 110 F degree
range especially for areas west of I-55. Elsewhere, areas east of I-
55 will see heat indices approaching 105 F degrees. No changes have
been made to the dangerous heat graphic for Sunday. /CR/

Sunday night through Friday night: Heat and humidity will be the
main concerns through the period with Tuesday expected to be the
most oppressive day.

Come Sunday evening our CWA will be on the eastern periphery of a
large 592dam high while a weak cold front approaches our northern
zones. This cold front is still expected to stall across our CWA as
surface ridging across the northern Gulf tries to remain stout. The
deep moisture including PWATs around two inches that pooled along
and ahead of the front will spread southwest across our CWA during
the day. Combined with the presence of the stalled frontal boundary
and daytime heating, rain chance will return and be greatest over
our eastern zones. Despite the rain chances, temperatures will climb
into the mid to upper 90s and combine with the high humidity to
result in peak heat index values between 105F and 110F over most of
the western half of the CWA Monday and then the whole CWA Tuesday. A
Heat Advisory will likely be needed for at least the west Monday and
likely the whole CWA Tuesday.

By Wednesday morning the large mid level high will have become
centered over the Four Corners region. A shortwave trough topping
the ridge will spill into our region during the day and lead to a
greater coverage of and perhaps an earlier start to convection. This
is expected to help hold temperatures a few degrees cooler than on
Tuesday and result in lower peak heat index values. The shortwave
trough is expected to be dropping south along the
Mississippi/Alabama stateline Thursday helping to maintain rain
chances over the southeast half of the CWA until tapering off from
the northwest Thursday evening. Friday the mid level high is progged
to build east back across our region. This will lead to warmer
temperatures and raise the concern of heat stress again. /22/

&&

.AVIATION...
-- Changed Discussion --
(06Z TAFS)
Issued at 1221 AM CDT Sun Jun 23 2024

VFR flight categories will prevail at area TAF sites over the
next 24 hours. Winds tonight will be calm to light from the
southwest around 3 knots. These will increase through late
morning, eventually becoming west southwesterly between 5-8 knots.
/19/
-- End Changed Discussion --

&&

.PRELIMINARY POINT TEMPS/POPS...
-- Changed Discussion --
Jackson       95  76  96  76 /  10   0  30  10
Meridian      98  75  97  74 /  10  10  30  10
Vicksburg     96  77  97  76 /   0   0  20  10
Hattiesburg   97  76  97  76 /  10   0  30  10
Natchez       95  75  95  75 /   0   0  20  10
Greenville    98  79  99  78 /  10  10  10  10
Greenwood     97  77  97  77 /  20  10  20  10
-- End Changed Discussion --

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
MS...Heat Advisory from noon today to 8 PM CDT this evening for
     MSZ018-019-025-034.

LA...None.
AR...Heat Advisory from noon today to 8 PM CDT this evening for
     ARZ074-075.
-- End Changed Discussion --

&&

$$

19