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915
FXUS62 KCAE 241845
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
245 PM EDT Fri May 24 2024

.SYNOPSIS...
A frontal boundary will approach the region Friday and is
expected to stall near the area resulting in chances of showers
and thunderstorms through the weekend. Another more organized
system is expected to be crossing the eastern US Monday and
Tuesday with additional chances for thunderstorms. Drier weather
is expected to return Wednesday.

&&

.NEAR TERM /THROUGH TONIGHT/...
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A very low amplitude 500 mb shortwave continues to approach the area
this afternoon with some scattered thunderstorms developing across
central GA as of 18z. The primary axis of highest instability still
remains to the west of forecast area, with generally between 1500-
2000 j/kg across the CSRA, falling to around 1000 j/kg in the
Midlands. HREF members generally were too slow with convective
initiation and are a bit too cool on temps and dew points, so
slightly higher instability across the area has been realized this
afternoon. While the HRRR and company were too slow with initiation,
their depiction of thunderstorm propagation and further development
seems very reasonable, spreading east into the CSRA between 20z and
00z. Convective coverage will likely increase across the entire area
throughout the evening but the severe threat still will remain
isolated in nature, so no surprise SPC continued the Marginal
risk across the area; shear remains very weak despite the
shortwave aloft and instability is borderline, with only minimal
mid-level dry air. HREF members generally continue shower and
elevated thunderstorm activity overnight thanks to moisture
convergence with PWAT`s over 1.6" and modest instability between
500-1000 j/kg MU CAPE. So PoPs remain elevated overnight but
the severe threat will be limited.
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&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
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Saturday and Saturday Night: An upper shortwave trough over the
region early in the day is expected to slide eastward and deepen
as it moves over the coast. Behind it, northwest flow aloft is
forecast to bring in slightly drier air; however, PWATs are
anticipated to remain above 1.5" through much of the afternoon
and evening as latest guidance indicates the drier air arrives
a bit slower than previous model runs. Upper ridging is also
forecast to begin building over the region, in general, but
shortwave energy moving through the main pattern should be
enough to kick off a round of isolated to scattered
thunderstorms. There remains some question on how much coverage
we`ll see because of a general lack of triggering mechanism in
the area. The potential for severe weather remains on the lower
side, but strong winds would be the main threat with any
stronger cells.

Sunday and Sunday Night: The upper level ridging continues to
strengthen over the region as southerly low-level flow becomes
more established. As a result, moisture begins to increase again
through the day and temperatures rise to the lower to mid 90s,
causing heat indices to approach, or even exceed, 100F in the
afternoon. Isolated to widely scattered showers and storms are
again possible, though it may be difficult to get much coverage
given the ridge overhead and another lack of triggering
mechanism. The higher chance of activity remains over the
northern portions of the forecast areas. If storms are able to
form, there remains potential for them to become strong to
severe with winds being the primary threat with the stronger
storms. However, the potential for any storms to form has been
on a downward trend.
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&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
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An upper trough over the central CONUS is forecast to begin
moving towards the region on Monday. An associated frontal
boundary is forecast to move through the area, sparking another
round of showers and thunderstorms across the forecast area.
With cooling heights aloft and a more pronounced triggering
mechanism, the potential for severe weather returns for Monday.
As it looks now, Monday looks to be the highest chance for
severe weather. The trough continues to pass over Tuesday,
bringing another round of showers and storms, but the severe
threat looks low at this point. Drier air is then expected to
move into the region for most of the rest of the period. Rain is
thus not anticipated through the forecast period, but there is
uncertainty between model guidance.
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&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
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VFR conditions generally expected during this forecast period,
outside of any shower-storm activity.

Convection is developing across central GA currently, slowing
moving towards the Augusta terminals. Expecting possible
thunderstorm activity to move into those terminals between
~19-21z, so a tempo group for TSRA has been included for those
sites. Scattered thunderstorm activity is expected to linger
into the evening for AGS and DNL, along with OGB. Confidence is
still too low for a TAF mention at CAE and CUB due to the timing
and coverage. Shower and storms are also possible for all sites
through roughly 08z, but again confidence is too low for
explicit TAF mentions but ran with VCSH overnight. Some
scattered areas of fog and stratus are possible overnight
outside and behind any showers.

EXTENDED AVIATION OUTLOOK...Restrictions possible at times
through early next week in afternoon and evening showers and
thunderstorms.
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&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...None.
GA...None.

&&

$$