Area Forecast Discussion
Issued by NWS Columbia, SC

Home |  Current Version |  Previous Version |  Text Only |  Print | Product List |  Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40
429
FXUS62 KCAE 290738
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
338 AM EDT Wed May 29 2024

.SYNOPSIS...
Drier and cooler weather will continue moving into the region as
high pressure builds in from the upper Mississippi Valley.
Moisture is expected to return to the region by the weekend. This
will result in mainly diurnally driven isolated to scattered
afternoon and evening showers and thunderstorms early next week.
Temperatures are expected to be at or slightly below normal
into the weekend then a warming early next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Morning analysis shows a deep upper low over the Great Lakes
region with and upper ridge over the intermountain west. At the
surface, weak high pressure continues to build into the region.
Satellite imagery shows some lingering mid level clouds across
the northern Midlands with some higher cirrus clouds passing
overhead.

A beautiful early summer day is expected with plenty of sunshine
expected and lower humidity with dewpoints in the 50s. The upper
trough axis will continue to drift eastward today and result in
northwesterly 500mb-700mb flow. Atmospheric moisture is
relatively low with ensemble mean PWATs around 50 percent of
normal and dewpoints mixing out into the lower 50s through the
afternoon. Forecast soundings confirm the significant dry air
throughout the atmospheric column and show a strong subsidence
inversion. High temperatures should be slightly cooler today
compared to Tuesday but remain above normal with highs in the
mid to upper 80s. A reinforcing cold front will push south
through the forecast area tonight bringing some cooler air to
the region. Skies should be mostly clear with good radiational
cooling expected and expect lows to drop into the upper 50s to
lower 60s.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
Dry northwest flow aloft as an upper level trough in the
Northeastern states dives southeast to off the Mid Atlantic and
Carolina coast Friday. Strong surface ridge centered over the
Great Lakes and Ohio Valley will be building to the south and
east, especially by Friday. The air mass will become quite dry
by Friday with precipitable water at or below 0.5 inches. A few
fair weather clouds across the north CWA Thursday as short wave
trough/upper level jet moves southeast across NC/northern SC.
Mainly Sunny skies Friday with strong subsidence and dry air.
Cold advection Friday so probably the coolest day of the week.
Highs both days in the low to mid 80s. Overnight lows falling
into the mid 50s by Friday night as more favorable radiational
cooling conditions expected with the surface ridge building into
the area.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
The ensembles suggest mid level ridging over the area early in
the weekend so expect temperatures to recover and moisture for
convection will be limited. The surface ridge will shift off the
coast by Sunday. A short wave trough moving east of mid
Mississippi Valley is expected to break down the ridge and
moisture increases early next week. The question is the degree
of moisture flux into the area. The ECMWF ensemble and GEPS
suggest a weaker short wave/less amplified than the GFS. This
results in a weaker moisture transport and stronger ridging over
the area into early next week. So, cut pops a bit Sunday
through Tuesday From the NBM although isolated to scattered
diurnally driven showers and thunderstorms can be expected
Sunday through Tuesday. Overall instability appears weak through
the period with even the GEFS, which is most aggressive with
pops, having relatively low probability of CAPE > 500 J/kg
through the period. Temperatures should warm to near normal with
surface ridge offshore and air mass modification.

&&

.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
VFR conditions expected through the 24 hr TAF period.

A dry air mass continues to build into the region today with a
secondary cool front pushing south through the Midlands tonight.
No morning fog expected due to large dewpoint depressions from
drier air with lower dewpoints. Light winds through sunrise
should pick up from the west-northwest around 5 to 10 knots by
late morning and some gusts to 15-18 knots possible during the
afternoon. Skies should be mostly clear through the period with
some scattered high clouds and mid afternoon diurnal cumulus
clouds.

EXTENDED AVIATION OUTLOOK...Restrictions not expected through
the end of the week. Low chance of restrictions this weekend.

&&

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

&&

$$