922
FXUS64 KMEG 142330
AFDMEG

Area Forecast Discussion
National Weather Service Memphis TN
630 PM CDT Sun Jul 14 2024

...New AVIATION...

.SYNOPSIS...
Issued at 257 PM CDT Sun Jul 14 2024

An upper level ridge of high pressure over the southern Rockies
will expand eastward in the lower Mississippi River Valley over
the next few days. This will result in warming temperatures across
the Midsouth, with heat indices in excess of 105. A Heat Advisory
has been issued for Monday for West Tennessee, the Missouri
bootheel, all of eastern Arkansas and northwest Mississippi. A
Heat Advisory will likely be need for all the Midsouth on
Tuesday.

Wednesday will see some moderation in temperatures north of
Interstate 40, due to increased clouds and thunderstorm coverage.
A weak cold front will pass through the Midsouth late Wednesday
night and Thursday, moderating temperatures as we head into next
weekend.

&&

.DISCUSSION...
(This evening through next Saturday)
Issued at 257 PM CDT Sun Jul 14 2024

Primary weather concern over the next few days remains the heat.
A 598dam 500mb height ridge centered over the 4-corners region
will deamplify and expand eastward into the southern plains and
lower MS River Valley through Tuesday. Relative to today, 850mb
temps over the Midsouth will warm 1 to 1.5C on Monday and another
0.5C on Tuesday. The right entrance region of a weak subtropical
jet may aid in the development of scattered storms over northeast
MS Monday afternoon, limiting the chances of 105 or greater heat
indices- but it will be close call. Over the remainder of the
Midsouth, heat indices in excess of 105 are more probable,
neccessitating a Heat Advisory for Monday. Later shifts will
likely expand the Heat Advisory through all the Midsouth on
Tuesday. The good news is that the probabilities of 110+ heat
indices are lower than it earlier appeared for Tuesday, and have
thus held off issuing an Excessive Heat Watch.

Wednesday will be a day of transition, as midlevel height falls
lower the excessive heat risk north of I-40, while increasing deep
layer shear and thunderstorm chances. With possible dewpoint
pooling in advance of a Wednesday night/early Thursday cold
frontal passage, there will be ample moisture for thunderstorms.
PWAT will range from 2 to 2.5 inches north of I-40 Wednesday
afternoon. To the south of I-40 heat headlines will likely be
needed on Wednesday.

Height falls will continue Wednesday night and Thursday, as a
midlevel trough axis rotates through. A surface cold front, though
not particularly well-defined, will drop into the Midsouth on
Thursday. By Thursday evening, thunderstorm chances will shift
south of I-40, as drier midcontinental air spreads in from the
north.

The front will likely stall over northeast MS Thursday night, as
weak midlevel flow transitions to a southwesterly direction.
Scattered daytime storms will be possilbe in the humid air around
this residual frontal boundary as we head into next weekend.

PWB

&&

.AVIATION...
(00Z TAFS)
Issued at 630 PM CDT Sun Jul 14 2024

VCTS will continue across the Mid-South for the next hour, before
activity decreases after sunset. Otherwise, VFR conditions with
winds remaining from the southwest through the current TAF period.
Afternoon VCTS will return tomorrow, with the greatest chance near
TUP.

&&

.MEG WATCHES/WARNINGS/ADVISORIES...
AR...Heat Advisory from 10 AM to 10 PM CDT Monday for ARZ009-018-
     026>028-035-036-048-049-058.

MO...Heat Advisory from 10 AM to 10 PM CDT Monday for MOZ113-115.

MS...Heat Advisory from 10 AM to 10 PM CDT Monday for MSZ001-007-008-
     010>012-020-021.

TN...Heat Advisory from 10 AM to 10 PM CDT Monday for TNZ001>004-
     019>022-048>055-088>092.

&&

$$

PUBLIC FORECAST...PWB
AVIATION...CMA