Area Forecast Discussion
Issued by NWS Columbia, SC

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533
FXUS62 KCAE 201814
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
214 PM EDT Mon May 20 2024

.SYNOPSIS...
High pressure will dominate the region through early Thursday
keeping fair and dry conditions in place along with warming
temperatures. A frontal boundary will approach the region
Friday and is expected to stall just north of the area
resulting in chances of showers and thunderstorms Friday into
next weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
Upper level ridging continues to shift over the region from the
west, while surface high pressure prevails to the northeast. The
deep layered ridging will result in strong subsidence through
tonight.

Cumulus/stratocumulus clouds are scattered across much of the
area this afternoon, but more extensive across the eastern
Midlands where moisture is just a bit deeper. These clouds
should generally dissipate by mid-late evening with the loss of
daytime heating, but some lingering cloud cover is possible
across the eastern Midlands. The northeast flow will persist
into this evening around 5-10 mph, before becoming more light
and variable tonight. Patchy fog is possible is the usual fog-
prone locations, but there are some hints in the short-range
ensembles that light fog is possible across the eastern Midlands
toward daybreak Tuesday. Lows will be slightly below normal due
to a dry airmass, with upper 50s to lower 60s expected by
daybreak Tuesday.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
High pressure aloft and at the surface will remain in place
across the region through midweek with upper ridging overhead
and surface ridge extending from the Mid-Atlantic coast through
the Carolinas. The atmosphere remains stable and dry during this
period with PWATs around 60-80 percent of normal and forecast
soundings showing a prominent subsidence inversion and
significant dry air in the mid and lower levels.

Therefore, no rainfall in the forecast through Wednesday night
as it should all remain well to the west associated with a low
pressure system lifting northeastward into the western Great
Lakes and cold front pushing into the Ohio/Mississippi Valleys.
Temperatures will be warming into the upper 80s to around 90
degrees near to above normal and overnight lows also above
normal.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
Ensemble guidance continues to favor one more rain free day on
Thursday under the influence of upper ridging with forecast
soundings showing a slightly weaker but still prominent
subsidence inversion. Surface ridge axis will be east of the
forecast area offshore on Thursday allowing for southerly flow
and PWATs are expected to rise slightly above normal with the
axis of highest moisture pooled along an approaching frontal
boundary over the southern Ohio Valley into the Mid-Atlantic
states.

Friday through the weekend, atmospheric moisture should remain
above normal and the upper ridge flattens in response to
shortwave energy moving through the 500mb flow which transitions
more zonal during this period. Above normal PWATs combining
with increasing instability and a series of shortwaves moving
over the region through the weekend will keep chances of rain in
the forecast. While it is still too far out to have much
confidence in possible severe weather, 60-70 percent of the
ensemble guidance shows SBCAPE values greater than 500 j/kg.
Temperatures are expected to remain above normal throughout the
period with highs in the upper 80s to possibly lower 90s.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
VFR conditions will prevail through 18Z Monday.

Scattered cumulus/stratocumulus, except broken at VFR levels at
KOGB, should prevail at the terminals through early this
evening, followed by clearing with the loss of daytime heating.
Winds will remain out of the northeast at 5-10 kt today,
becoming light and variable later this evening and overnight,
increasing once again from the northeast by mid-morning Tuesday
as high pressure lingers to the northeast of the area. As
usual, patchy fog is possible mainly at KAGS in the 08-12Z time
frame.

EXTENDED AVIATION OUTLOOK...No significant flight restrictions
are currently anticipated through Wednesday. Low probability of
restrictions during the late week period from afternoon and
evening convection.

&&

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

&&

$$