102
FXUS64 KJAN 170158 AAA
AFDJAN

Area Forecast Discussion...UPDATED
National Weather Service Jackson MS
858 PM CDT Fri Aug 16 2024

...New MESOSCALE UPDATE...

.MESOSCALE UPDATE...
Issued at 856 PM CDT Fri Aug 16 2024

Tonight`s forecast will be a broad repeat of last night`s, eschewing
the errant thunderstorm in Forrest County expected to die off over
the next hour or so: Overnight tonight into the early morning hours
we will see another bout of warm, steamy, and calm conditions. Lows
are expected to be between 75F-80F across the region tonight with
relative humidity values in the 95% range, making for another
oppressively muggy night, tonight. Sky conditions are expected to be
partly cloudy which will contribute to our warm overnight lows, as
the surface struggles to radiate out efficiently. There is a
organized convective system upstream in Arkansas moving towards the
region, this system is expected to continually weaken and dissipate
overnight before reaching us. The forecast continues to be on track
tonight and tomorrow./OAJ/


&&

.DISCUSSION...
Issued at 216 PM CDT Fri Aug 16 2024

Tonight through late next week...

Dangerous heat remains the primary concern in the near term as our
area remains on the eastern periphery of an upper ridge centered
over Texas. With low level moisture holding steady, temperatures
should only drop to the mid to upper 70s tonight. Therefore, will
maintain heat headlines overnight.

Temperatures are unlikely to change much tomorrow with mainly upper
90s and a few 100s possible. Dewpoints should hold in the mid to
upper 70s, resulting in heat indices in the 105 to 112 range across
the area. Excessive heat warning will continue tomorrow for much of
the area, and a heat advisory will continue in the east.
Additionally, these hot and humid conditions, along with increased
flow and favorable shear vector orientation could support isolated
to scattered thunderstorms tomorrow afternoon with damaging wind
gusts the primary hazard. There is some uncertainty however
regarding the potential for remnant outflow to disrupt the
environment and guidance has downtrended on chances. Should the
environment remain relatively untapped, favorable convective
parameters should support at least a marginal severe risk. Rainfall
totals look to be around quarter to half inch, and it should be
spotty, with widespread soaking rain unlikely.

Heat is likely to continue into Sunday. Have extended the heat
graphic in HWO to capture this. Moisture pooling ahead of the
advancing cold front should hold dewpoints in the mid to upper 70s
for another day, temperatures warm into the upper 90s and low 100s.
Heat indices once again peak in the 105 to 112 range. Timing of the
front though does introduce a big of uncertainty that could impact
heat risk on Sunday, so confidence isn`t quite high enough at this
time to pick a definitive area for heat headlines. Showers and
storms are possible Sunday too, however a lot is dependent on
Saturday and guidance has trended down on chances for Sunday as
well.

By Sunday night, an upper trough will drive the cold front south,
with dry air and seasonal temps in its wake. Next week should be
fairly dry and seasonal with temperatures mainly in the low 90s.
Troughing to the east and ridging to the west should maintain NW
flow through much of next week, keeping dry conditions. By the end
of next week, moisture begins to return as low level flow turns
southerly. This should reintroduce low rain chances in the south.
Some guidance tries to develop a low to our southwest by next
weekend, in which case, rain chances should generally increase./SAS/

&&

.AVIATION...
(00Z TAFS)
Issued at 700 PM CDT Fri Aug 16 2024

Remaining SHRA/TSRA activity will diminish in coverage/intensity
as we go through the evening. Overall, VFR conditions will prevail
through the forecast period along with light surface wind, but
patchy areas of early morning could impact sites early Sat
morning. By Sat aftn, iso/sct TSRA potential should develop, but
confidence is lower than usual regarding where activity may
initiate due to uncertain boundary interactions./EC/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       76  98  77 101 /  10  30  20  20
Meridian      75  99  73 101 /  10  50  20  20
Vicksburg     76  98  77 101 /   0  10  10  20
Hattiesburg   76  99  76 101 /  40  30  10  10
Natchez       76  97  76 100 /  10  10   0  10
Greenville    77  97  76 100 /  10  10  20  20
Greenwood     77  98  76  99 /  10  20  20  20

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...Excessive Heat Warning until 8 PM CDT Saturday for MSZ018-019-
     025>029-032-034>037-040>044-047>050-053>057-059>066-072>074.

     Heat Advisory until 8 PM CDT Saturday for MSZ030-031-033-038-039-
     045-046-051-052-058.

LA...Excessive Heat Warning until 8 PM CDT Saturday for LAZ007>009-
     015-016-023>026.

AR...Excessive Heat Warning until 8 PM CDT Saturday for ARZ074-075.

&&

$$

OAJ/SAS20/EC