Area Forecast Discussion
Issued by NWS Columbia, SC

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147
FXUS62 KCAE 170713
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
313 AM EDT Mon Jun 17 2024

.SYNOPSIS...
High pressure, drier conditions, and near normal temperatures
are expected through mid-week. Unsettled conditions are possible
by late in the week into the weekend as moisture moves in from
the Atlantic. Well above normal temperatures are expected by
Saturday and Sunday.

&&

.NEAR TERM /THROUGH TONIGHT/...
Late night satellite imagery shows a band of high level
cloudiness moving into the Midlands from the CSRA. A few areas
of low clouds are also starting to develop, especially in the
northern Midlands where radar continues to show a few light
showers over the northern part of Lancaster County. The showers
seem to finally be dissipating which should put an end to the
rain threat tonight. Latest guidance continues to support
increasing cloudiness, especially across the western Midlands
and CSRA. The clouds should limit cooling tonight if they
develop as the models suggest with forecast lows in the upper
60s to around 70 degrees in the east and lower 70s in the west.

Strong upper ridging will dominate our weather today. At the
surface, winds are expected to generally be out of the east with
high pressure centered to our northeast. Mainly dry conditions
are expected across the forecast area but a few showers or
thunderstorms cannot be ruled out due to the combination of
strong surface heating, the sea breeze boundary, and PWATs
between 1.5 and 1.75 inches. Morning low clouds should scour out
and transition to partly to mostly sunny skies by midday with
highs in the upper 80s to lower 90s. Moisture decreases tonight
with mostly clear to partly cloudy skies expected and overnight
lows in the upper 60s.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
The region will be positioned along the southern periphery of a
strong high pressure ridge centered over New England and the
northern Mid Atlantic Tuesday and Wednesday. At the surface, an
onshore flow off the Atlantic will prevail. Despite the onshore
flow, deep layered moisture will be lacking. Long range ensemble
mean precipitable water values are around 1 inch on Tuesday and 1-
1.25 inches on Wednesday, well below normal for this time of year.
Given the dry atmosphere and subsidence aloft, expect rain-free
conditions during the short term period. Temperatures will be
moderated some by the cooler onshore flow. Therefore, this period
will likely consist of the coolest temperatures of the week, with
seasonable highs in the upper 80s to around 90.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
Strong upper level ridging will begin to sink south across the Mid-
Atlantic and Carolinas Thursday and Friday. Operational long-range
models and to some extent long-range ensembles suggest an inverted
upper trough retrograding toward the southeast US coast on Friday
beneath the strong ridge. While the signal has been weakening during
recent runs, there is the potential for a trough or area of low
pressure to develop offshore and move toward the southeast US coast
Friday into Saturday, and the latest Tropical Weather Outlook from
NHC indicates a 30% chance of tropical formation. Despite any
potential tropical development, there does appear to be at least a
notable increase in moisture across the area supportive of unsettled
conditions in terms of diurnal convection on Friday and to a lesser
extent on Saturday.

Ensembles then support strengthening ridging at the surface and
aloft over the western Atlantic later Saturday and Sunday. This will
lead to well above normal temperatures over the weekend. In fact,
the long range ensemble forecast shows the probability of
temperatures reaching or exceeding 100 degrees to be 25-35% by
Sunday. The NWS HeatRisk also shows Category 3/Red conditions across
much of the area on Sunday, indicating a potential Major Risk of
heat-related impacts.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
Restrictions Possible this Morning due to Low Ceilings,
Especially at AGS/DNL....

Late night satellite imagery shows a band of high level
cloudiness moving into the Midlands from the CSRA. A few areas
of low clouds are also starting to develop, with MVFR visibility
already being reported at AGS. Latest guidance continues to
support the development of widespread low clouds over the
western Midlands and CSRA, impacting AGS and DNL. Confidence
remains highest at these locations with higher ceilings in the
TAFs at CAE/CUB and OGB.

Strong upper ridging will dominate our weather today. At the
surface, winds are expected to generally be out of the east
between 5 and 10 knots with high pressure centered to the
northeast. Morning low clouds should scour out and transition to
partly to mostly sunny skies by 15Z. Mainly dry conditions are
expected at the terminals but a passing shower or thunderstorm
cannot be ruled out. Have omitted mention of this in the TAFs
due to low confidence.

EXTENDED AVIATION OUTLOOK...Low probability of significant
restrictions.

&&

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

&&

$$