Emmalane, Georgia Weather Forecast Discussion

949
FXUS62 KCHS 181800
AFDCHS
Area Forecast Discussion
National Weather Service Charleston SC
200 PM EDT Thu Sep 18 2025
.SYNOPSIS...
Weak high pressure will extend across the region this week.
Stronger high pressure will build into the region over the
weekend and early next week, while a coastal trough develops
offshore.
&&
.NEAR TERM /THROUGH TONIGHT/...
Rest of This Afternoon: The local region will remain under the
influence of broad troughing aloft as cyclonic flow in the mid and
upper levels dominates over New England. At the surface, weak high
pressure will prevail across the southeastern states. There is
likely enough forcing aloft to trigger some showers this afternoon,
mainly west of I-95. However, forecast model soundings and the 12Z
KCHS RAOB sounding show a significant amount of dry air aloft, which
would inhibit shower formation. The latest runs of the HRRR continue
to decrease the shower coverage. Therefore, this forecast features
the 01Z NBM PoPs which are mainly around 10%. Any stray shower that
is able to form will likely dissipate by this evening. Some gusty NE
winds are possible this afternoon along the immediate coastline
associated with the afternoon sea breeze. Temperatures this
afternoon will reach into the mid to upper 80s.
Tonight: Some high clouds early tonight and low clouds developing in
the early morning hours will limit the amount of radiational cooling
tonight. Low temperatures are forecast to dip into the mid 60s
inland with low 70s along the beaches.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
Aloft, weak mid-upper lvl troughing should persist across the
Southeast with subtle lobes of h5 vort energy meandering nearby
through Saturday, before subtle ridging takes place on Sunday. At
the sfc, weak high pressure will prevail into early Saturday, prior
to becoming reinforced by a stronger wedge of high pressure from the
north starting late Saturday into Sunday. The pattern should support
mainly dry conditions through Saturday, especially with deep
moisture lacking across the region, but a few light showers could
arrive with the wedge front on Sunday. Additionally, breezy
northeasterly winds are possible Sunday (20-25 mph), highest along
coastal areas where the pressure gradient is more enhanced. 1000-
850mb thickness levels along with mostly sunny conditions suggest
temps to remain above normal, with afternoon highs in the upper 80s
to lower 90s each day (warmest across interior Southeast Georgia).
However, cooler air and some clouds arrive with the wedge/front
later on Sunday, which could limit overall heating potential across
Southeast South Carolina to start off the week. Overnight lows
should remain mild, generally in the mid-upper 60s inland to lower
70s closer to the coast each night.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
Aloft, weak mid-lvl ridging will gradually give way to a trough
passing by to the north, before ridging returns/strengthens across
the Southeast heading into the middle of the week. At the sfc, high
pressure will wedge southward into the Southeast States Sunday night
into Monday, likely presenting cooler conditions, before coastal
troughing develops and mid-lvl ridging returns Tuesday morning and
persists into midweek. Lower-end rain chances remain in the latest
forecast each afternoon (20-30%), with the bulk of activity
occurring along coastal areas where moisture convergence is
strongest along a front and where coastal troughing also leads to
showers advecting onshore within a northeasterly wind. Precip
activity could then trend further inland on Wednesday as moisture
deepens near the remnant front extending across Southeast South
Carolina/Southeast Georgia. In general, high temps should peak in
the low-mid 80s (warmest across inland Southeast Georgia) Sunday and
Monday, followed by upper 80s/around 90 across the interior on
Tuesday. Overnight lows remain in the mid-upper 60s inland to lower
70s closer to the coast.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
Prevailing VFR through the 18Z TAF period at KCHS/KJZI. KSAV
will also remain VFR through this evening and into tonight.
However, low clouds are forecast to develop across SE GA,
bringing the risk for MVFR/IFR cigs. The 18Z TAFs introduce a
few hours of MVFR conditions Friday morning at KSAV. It is
possible that IFR conditions may need to be included with a
future TAF issuance.
Extended Aviation Forecast: VFR conditions are expected at
CHS/JZI/SAV terminals through Sunday. Brief flight restrictions are
then possible with low clouds and showers Sunday and Monday.
Gusty northeasterly winds (15-20 kt) are possible on Sunday as
well.
&&
.MARINE...
Rest of Today and Tonight: The sea breeze this afternoon will yield
S winds gusting to around 15 to 20 knots this afternoon along the
coastline. Gusty winds will diminish this evening and tonight, with
SE winds less than 10 knots in the forecast. Seas should average 1
to 2 ft, with some 3 ft seas in the 20 to 60 nm offshore GA
waters.
Friday through Tuesday: Weak high pressure will prevail across local
waters into early Saturday, resulting in no marine concerns. In
general, southerly winds will be no higher than 15 kt with seas
ranging between 2-4 ft, largest across outer Georgia waters. High
pressure will begin to wedge south across the region over the
weekend, placing a stronger pressure gradient across local waters
between a wedge front and troughing across the Atlantic. The front
should arrive across local waters Sunday, allowing an enhanced
pressure gradient to persist into early next week. Conditions could
support Small Craft Advisories across a portion of local waters
starting as early as Saturday night, then prevail across most local
waters Sunday, before improvement occurs on Monday. During the peak
of the event (Sunday), northeasterly winds gusting around 25 kt and
seas between 4-6 ft are anticipated. Conditions are then expected to
remain below Small Craft Advisory levels by Tuesday.
Rip Currents: Gusty northeasterly winds developing between strong
high pressure inland and coastal troughing offshore along with
increasing swell will favor a Moderate Risk of rip currents along
Georgia beaches Saturday. Conditions could support an enhanced risk
of rip currents along all beaches Sunday.
&&
.TIDES/COASTAL FLOODING...
Strong northeasterly winds are expected to create larger tidal
departures this weekend, which could result in tide levels
approaching 7 ft MLLW in Charleston Harbor starting with the
Saturday evening high tide cycle. The risk for minor coastal
flooding should continue into early next week. Coastal Flood
Advisories could eventually be needed for minor saltwater flooding
in Charleston and Coastal Colleton Counties.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...None.
&&
$$
NEAR TERM...CPM
SHORT TERM...DPB
LONG TERM...DPB
AVIATION...CPM/DPB
MARINE...CPM/DPB

NWS CHS Office Area Forecast Discussion