743
FXUS62 KCAE 021331
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
Issued by National Weather Service Greenville-Spartanburg SC
931 AM EDT Thu May 2 2024

.SYNOPSIS...
Upper ridging and surface high pressure will continue to build
back into the region Thursday with high temps pushing 90F. Much
the same expected for Friday before rain chances steadily
increase late Friday evening into Saturday. Deep moisture
convergence coinciding with an upper level trough will drive
widespread showers and isolated thunderstorms Saturday.
Lingering moisture and little changes aloft will yield further
shower-storm chances Sunday through Wednesday.

&&

.NEAR TERM /THROUGH TONIGHT/...
Dense fog has cleared out of the area, prompting the
cancellation of the Dense Fog Advisory early. Minor adjustments
to near term temperatures and winds. By 1000 am, surface ridge
centered off the coast and upper ridge will be building across
the area. Boundary layer temperatures this afternoon are a few
degrees warmer than yesterday and soundings show subsidence
inversion. Low level flow will be more southeast this afternoon
which could keep temps down slightly given maritime influence,
but think highs around CAE and AGS will be around 90 degrees. So
went slightly above the NBM and overall consensus guidance for
highs. Little change in the air mass tonight, so clear skies
with maybe some patchy early morning fog. Lows mainly in the low
60s although slightly cooler in the SC Piedmont.

&&

.SHORT TERM /FRIDAY/...
Mid-upper level ridging will begin to flatten out Friday as a
series of shortwaves push through the ridge axis. Offshore
surface ridging will consequently weaken slightly, but will
shift far enough east to allow southwesterly to develop below
500mb. Moisture advection will be fairly slow however, keeping
PWAT`s stuck around 1.0" through later Friday and thus keep
precip chances low until late Friday evening; hi-res guidance
and global deterministic push the vast majority of resolved
diurnal precip into the extreme western CSRA and Upstate.
Sufficient moisture convergence for scattered precip in the CSRA
and Midlands will arrive overnight Friday and Saturday morning
with PWAT`s jumping over 1.5" as a sharper 500-250mb trough
slides into AL-GA. The poor diurnal timing with this initial
moisture surge should prevent much in the way of thunderstorm
activity but some scattered showers will likely develop.
Diurnal heating, the approaching shortwave aloft, and strong
moisture convergence with PWAT`s over 1.75" will yield
widespread showers and storms Saturday afternoon. Thunderstorm
activity will likely remain weak however as only modest
instability will develop with meager mid-level lapse rates and
cloud cover; GEFS prob of > 500 J/kg is ~80% for most of the
area, but > 1000 J/kg is only 10-20%. Organized convection is
also not expected as very weak mid-level flow will only muster
0-6km shear of 10-15 knots.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
A summer-like pattern is expected to develop as we move late in
the weekend and into next week with broad ridging remaining
across the SE CONUS. NAEFS highlights this period pretty clearly
with slightly above average heights, temps, and PWAT`s yielding
a favorable setup climatologically for diurnal shower-storms
each day. While the ridge will remain anchored aloft, some
shortwaves associated with a deep trough over the north-
central CONUS will provide some further focus for lift and
precip chances, especially on Monday, with the conditional
unstable airmass lingering. GEFS and ECE steadily increase
instability each afternoon as the airmass steadily warms with
southwest low- level flow expected to continue; probs of > 1000
J/kg are over 50% by Monday. Towards the end of the longer term
period and into late next week, well above average temps are
expected to develop; there is increasing potential for high
temps in the low- mid 90`s (10-15 degrees above average) as GEFS
and EC members come into tighter agreement.

&&

.AVIATION /14Z THURSDAY THROUGH MONDAY/...
Restrictions in fog early this morning.

Pressure ridge across the area. Dense fog has developed at the
OGB terminal. Satellite showing fog/stratus moving inland toward
the CAE and CUB terminals at 10z. Drier air near AGS and DNL so
fog threat appears lower at those terminals.  A sea breeze
front has moved into central SC and dew points have come up a
bit from OGB to CAE.

Will continue with MVFR fog at CAE/CUB with tempo IFR through
13z...the fog appears to be just to the west of CAE. LIFR
visibility at OGB. After the fog lifts, expect scattered cumulus
in the afternoon especially in eastern SC associated with sea
breeze. Winds light and variable early then favoring southeast 5
to 10 knots in the afternoon.

EXTENDED AVIATION OUTLOOK...Late night/early morning fog and stratus
possible through the period. Increased potential for showers and
thunderstorms Friday afternoon through Monday.

&&

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

&&

$$