563
FXUS62 KCAE 040729
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
329 AM EDT Wed Jun 4 2025

.SYNOPSIS...
A return to a more active weather period begins today with
increasing deeper moisture as an upper trough lifts northward
from the Gulf. Widespread showers with scattered thunderstorms
expected this afternoon into Thursday with a warmer and drier
day on Friday, then returning over the weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
Key Message(s):

- Significant increase in atmospheric moisture leading to increased
rain chances today and tonight
- Cooler and cloudy with moderate to heavy rain late afternoon and
tonight

Upper ridging over the region is giving way to lowering 500mb
heights as the upper low over the eastern Gulf begins to lift
northward today. Satellite imagery shows widespread higher clouds
spreading northward into SC and expect clouds to continue to
increase through the day with ceilings lowering through the day as
atmospheric moisture increases significantly by this evening.
PWATs are around an inch or less but a strong gradient exists
across far southern SC into eastern GA.

Continued deep easterly flow off the Atlantic from the surface up to
above 500mb will support PWATs rising significantly to over 2 inches
by 00z in the southeast Midlands and across the entire forecast area
by 06z tonight. Regional radar already showing scattered showers
moving onshore across southeast GA and these shower will
gradually shift northward through the day as isentropic lift
increases and the combination of surface heating and some
atmospheric destabilization and shortwave energy lifting
northward should yield increasing rain chances through the day
from southeast to northwest with the best chances of rain across
the eastern Midlands and lower CSRA.

As the upper trough lifts northward tonight an inverted surface
trough develops along the coast with weak surface low development
which should focus the higher rainfall totals in the vicinity of the
Coastal Plain and far eastern Midlands. WPC has much of the area
outlooked in a marginal risk of excessive rainfall and this seems
reasonable given forecast soundings this afternoon and tonight
become very moist adiabatic with PWATs over 2 inches and rainfall
should be quite efficient. Cannot rule out the possibility of some
scattered thunderstorms but instability is not overly strong with
extensive cloud cover expected and severe threat is quite low. Any
training of moderate to heavy showers or thunderstorms will bring a
possibility of isolated localized flooding. Temperatures today
should be cooler than the previous days with the northern Midlands
last to get the overcast conditions so warmest temperatures expected
there with highs ranging from the upper 70s lower CSRA to lower 80s
northern Midlands. Rain continues tonight across much of the area
but focused across the easter Midlands and Pee Dee region overnight.
Extensive cloud cover and precipitation should limit radiational
cooling and expect lows in the mid to upper 60s.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
Key Message(s):

- Rain chances should depart on Thursday afternoon, with clouds
  quickly clearing
- Warmer and drier on Friday

Departing upper level low is expected to dictate the weather
both Thursday and Friday. It`ll be slowly pushing away on
Thursday, with high PWs still remaining across the area for the
first half of the day. HREF guidance suggests that our best rain
chances should fall in the period prior to about 2p on Thursday
as the surface low develops and treks across the area Thursday
morning. Thereafter, strong subsidence behind the surface and
upper low is expected to drive PWs back to near normal (from the
>2" range Thursday morning). Have adjusted PoPs to reflect
this. Its also worth noting how the guidance has trended with
this system, consistently bringing rainfall in earlier and
earlier and leading to a quicker departure as well. So its
possible that continues and leads to rain chances being a bit
lower Thursday afternoon than what I have in there right now.
Temps should be below normal everywhere, albeit temps may bump
up a bit if clouds clear quicker in the CSRA. Overnight, "drier"
air and subsidence will continue to overspread the area, with
lows in the mid 60s. Friday should feature lower rain chances as
we`ll be between systems & still dominated by subsidence from
the departing upper low. It will be much more summer like,
though, with highs back in the lower 90s and dewpoints likely in
the low 70s. Expect partly cloudy skies on Friday night with
lows in the upper 60s and lower 70s.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
Key Message(s):

- An active pattern is expected during the extended period, with
  multiple chances for showers and thunderstorms.

- Warm and muggy conditions expected into early next week.

In general, the long term looks fairly unsettled. Guidance
continues to be in fairly good agreement that the synoptic
pattern should evolve from somewhat zonal to start the period
into relatively deep troughing by this time next week. LREF
members & operational models are in good agreement on this
generality, leading to higher than normal forecaster confidence
in at least that. The sensible weather from this pattern is a
bit more uncertain. To start off, a low pressure system is
forecast to push a cold front towards and slowly through the
area on Saturday. A compact shortwave may actually be associated
with this as well, which could set the stage for some strong
storms on Saturday afternoon. This is highly uncertain at this
point as the track & amplitude of the shortwave is going to
modulate any severe threat that may materialize. But with LREF
joint probability of >1000 j/kg CAPE & >30 kts 6km shear around
30-40%, that signal is good enough to get my attention. ML
guidance has highlighted Saturday as a day to pay attention to
as well, so that is probably our best bet for anything
strong/severe in the long term at this point. Doubtful that the
front pushes fully through the region, and even if it does, it
should push northward again quickly Sun/Mon as deep troughing
establishes itself to our west. This should lead to increase
shower/storm chances, especially early next week. Temps should
be near normal given the expectation of daily storm chances,
with above normal overnight temps given copious surface
moisture.

&&

.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
VFR conditions expected to deteriorate at times with MVFR/IFR
ceilings possible this morning potentially continuing through
the day and returning tonight.

Satellite imagery showing higher clouds spreading northward
associated with an approaching upper low and low level stratus
developing across parts of the Midlands with increasing
isentropic lift and upslope flow. MVFR cigs expected to develop
during 09z-12z time frame especially at CAE/CUB and OGB with
lower confidence at AGS/DNL. Increasing moisture today will
yield widespread clouds and lowering cigs with possible MVFR
cigs persisting through the day but higher confidence in
returning by this evening as rain overspreads the region. Winds
will pick up from the east to around 10 knots by late morning
and continue through the afternoon.

EXTENDED AVIATION OUTLOOK...Continued rainfall and restrictions
into Wednesday night and Thursday morning. Moisture remains in
place over the area through much of the extended leading to
potential early morning restrictions and diurnal convection each
day.

&&

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

&&

$$