Bluffton, South Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

501
FXUS62 KCHS 160640
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
240 AM EDT Mon Mar 16 2026

.WHAT HAS CHANGED...
A Freeze Warning has been issued for parts of the area for
Tuesday morning. The Aviation section has been updated for the
06z TAF issuance.

&&

.KEY MESSAGES...
- 1) An isolated severe thunderstorm or two will be possible
 across southeast Georgia and southeast South Carolina through
 daybreak.

- 2) A powerful cold front will sweep through southeast Georgia
  and southeast South Carolina today, bringing an increased
  risk of severe thunderstorms, very gusty winds outside of
  storms, and brief bursts of moderate to heavy rainfall. The
  entire area is highlighted in an Enhanced Risk (level 3/5) for
  severe weather with the SPC Day 1 Severe Weather Outlook.

- 3) Frost/freeze is possible tonight through Wednesday night.

&&

.DISCUSSION...
KEY MESSAGE 1: An isolated severe thunderstorm or two will be
possible across southeast Georgia and southeast South Carolina
through daybreak.

The forecast area will sit within the warm and moist south to
southwesterly flow ahead of strong cold front to the west. Hi-
res model guidance suggests we will see periodic clusters of
thunderstorms develop and pass through, as there is a corridor
of 500-1,000 J/kg of MLCAPE. Effective bulk shear is currently
in the 25-35 knot range, but should continue to strengthen
overnight as increasing low and mid-level flow spreads in. In
fact, the KCLX VWP suggests there is already 35-40 kt of flow in
the 2-4 kft layer. We`ve already seen some excitement as a
strong thunderstorm developed across western Charleston County
and produced a 50 kt gust at KCHS and golf ball sized hail in
Goose Creek around 11-11:30 pm. All of this to say that there
will be an isolated severe threat through sunrise with any
clusters of showers and storms that develop and move through the
area. Perhaps the threat is highest along the coast, but it
could occur anywhere.

KEY MESSAGE 2: A powerful cold front will sweep through
southeast Georgia and southeast South Carolina today, bringing
an increased risk of severe thunderstorms, very gusty winds
outside of storms, and brief bursts of moderate to heavy
rainfall. The entire area is highlighted in an Enhanced Risk
(level 3/5) for severe weather with the SPC Day 1 Severe Weather
Outlook.

As we have discussed for several days now, a strong cold front
will sweep across southeast GA/SC and bring several hazards to
the area.

Severe Thunderstorms: The primary hazard associated with this
cold front will be the potential for significant severe weather.
Overall, the near storm environment appears to be on track
consistent with what we have seen for a number of forecast
cycles. A very strong wind field will overspread the area,
resulting in impressive ambient shear. Guidance suggests 0-6km
shear on the order of 50-60 kts, 0-3 km shear on the order of
40-50 kt, as well as pockets of SRH values up around 200 m2/s2.
Model soundings continue to mostly show nearly unidirectional
shear so it makes sense that the SRH values aren`t particularly
high. The biggest change noted this morning is the much earlier
arrival time in the suite of hi-res models. This earlier arrival
time will have notable impacts on the overall severe threat,
mainly in the form of lower instability values. Model soundings
now suggest MLCAPE in the 500-1,000 J/kg range, with a few
pockets of values in excess of 1,000 possible. This lower
instability will lessen the potential of discrete cell
development ahead of the line and will favor more linear bands.
Soundings also show considerable mid-level dry air, yielding
DCAPE values into the 700-900 J/kg range. So, the primary threat
remain damaging wind gusts (with potential for 75+ mph gusts),
an isolated line-embedded QLCS tornado or two, and a much lower
hail threat compared to previous forecasts. Another thing to
keep an eye on is the fact that near-surface winds are expected
to be from 210 degrees which means that at some point up the
coast, trajectories will start to be sourced from the nearby
cooler shelf waters. This marine influence will likely begin
around and north of the Savannah River entrance, potentially
altering and lower the severe weather threat for the immediate
SC coast from around Hilton Head, to Beaufort, Edisto,
Charleston, and McClellanville.

The earlier arrival time of the convective line will lead to
some notable adjustments for the timing of the severe threat.
The line should be knocking on the door of Jenkins, Candler, and
Tattnall counties ~9-10am, the Savannah area around 11am-noon,
and the Charleston area around 1-2pm. This would put the main
convective line offshore by around 2-3pm, which would be the end
of the severe threat.

Gusty winds: The strong wind field across the area will produce
gusty winds outside of thunderstorms. Strong momentum and the
onset of mixing should produce an environment suitable to
increasing gusts beginning around sunrise and continuing until
the front moves offshore. Gusts into the 30-35 mph range should
be relatively common just about everywhere, with the best gust
potential into portions of the Charleston area region. Gusts in
excess of 40 mph will be possible, and a Wind Advisory remains
in effect for the Charleston metro area. Also, a Lake Wind
Advisory is in effect for Lake Moultrie.

Rainfall: The convective line will certainly be capable of
producing short-lived bursts of moderate to heavy rainfall.
However, the line will be moving fast enough to prevent too much
residence time and will therefore reduce the heavy rainfall
threat. Rainfall amounts should mostly end up the 0.25-0.50"
range with some locally higher amounts possible. Therefore, the
risk for intense rainfall producing flooding remains rather low.

KEY MESSAGE 3: Frost/freeze is possible tonight through
Wednesday night.

Cold high pressure will spread over the area behind the cold
front tonight. Temps will quickly drop this evening. A brief
advection freeze is expected Tuesday morning, mainly across far
interior GA/SC where temps could dip to 30-32F. We felt
confident enough that we upgraded the Freeze Watch to a Warning,
and also added Inland Colleton County.

Tuesday night the high will be centered close to the area,
allowing surface winds to decouple in the evening. Skies should
be clearing out during the evening, so good radiational cooling
will occur overnight. Temps are expected to dip into the upper
20s far inland with lower to middle 30s elsewhere. Even where
temps don`t hit freezing, frost formation seems pretty likely.
We will likely need another round of Frost/Freeze headlines for
Tuesday night.

Wednesday night could also feature some frost issues across the
inland half of the area where temps dip to the low/mid 30s and
skies remain mostly clear.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
The 06z TAF period begins with VFR conditions at KCHS, KJZI,
and KSAV. The first issue is that there could be a short window
of LLWS before winds increase. It should be short-lived as the
low-level wind field is increasing and will become breezy even
before sunrise. Thereafter, the main forecast concern is for the
arrival of a line of thunderstorms later today. Based on
expected faster timing we have moved the TSRA TEMPO groups
earlier. For KSAV, the line is expected to move through during
the 15-17z time period and for KCHS and KJZI it is expected to
be 17-19z. A period of very heavy rain with IFR visibilities
will be possible as well as very strong winds. We have
introduced gusts up to 40 kt with the thunderstorms and there is
potential for even higher. Once the line moves through there
will be a period of showers behind it before precip comes to a
complete end this evening. Winds will ramp up quickly after
sunrise and will be gusty in advance of the thunderstorm line.
Winds will remain gusty while turning westerly this evening.

Extended Aviation Outlook: VFR conditions are expected to
prevail.

&&

.MARINE...
Strong low-level wind fields will result in gusty winds over
the waters today as a strong cold front approaches. 35 kt gusts
are likely over the SC nearshore waters and Charleston Harbor
where we maintained a Gale Warning. Small Craft Advisories exist
elsewhere.

Winds will abruptly shift to WNW by early this evening after
the cold front sweeps through. The gusty winds and elevated seas
will subside by Tuesday morning.

&&

.EQUIPMENT...
The KCLX radar is scheduled for radome panel replacement March
17-20, 2026. The radar will be down during this time. Users are
encouraged to use data from the following nearby radar sites
during the maintenance outage:

KCAE - Columbia, SC
KLTX - Wilmington, NC
KJAX - Jacksonville, FL
KVAX - Moody AFB, GA
KJGX - Robbins AFB, GA

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...Freeze Warning from 4 AM to 10 AM EDT Tuesday for GAZ087-088-
     099-100-114-115.
SC...Freeze Warning from 4 AM to 10 AM EDT Tuesday for SCZ040-042-
     043.
     Lake Wind Advisory until 2 AM EDT Tuesday for SCZ045.
     Wind Advisory from 8 AM this morning to 8 PM EDT this evening
     for SCZ050-052.
MARINE...Gale Warning until 8 PM EDT this evening for AMZ330-350-352.
     Small Craft Advisory until noon EDT Tuesday for AMZ354-374.

&&

$$

BSH/JRL