sc discuss
Office: CHS
FXUS62 KCHS 131813
AFDCHS
Area Forecast Discussion
National Weather Service Charleston SC
213 PM EDT Sun Sep 13 2026
.WHAT HAS CHANGED...
All sections updated.
&&
.KEY MESSAGES...
- 1) Limited rain chances today and Monday, with record challenging
high temperatures forecast Monday.
- 2) Cooler and drier conditions expected Tuesday through mid
week.
- 3) Minor coastal flooding possible with the Tuesday midday
high tide along the Charleston and Colleton county coasts.
&&
.DISCUSSION...
KEY MESSAGE 1: Isolated showers and thunderstorms are forecast to
develop along the sea breeze this afternoon.
Despite a PWAT of 2.31 inches with this morning's 12Z KCHS RAOB
Sounding, conditions are forecast to dry out into the afternoon
hours as a shortwave trough advances towards the local forecast
area. This shortwave can be easily seen on the GOES mid-level water
vapor imagery, as of 17Z roughly located just to the west of
Jenkins/Screven/Allendale counties. The KCLX radar has begun to
detect isolated showers over southeastern GA. These showers are
forming just ahead of the shortwave, likely initiating with the
assistance of the sea breeze. Most model guidance from this morning
paint a rather benign picture of isolated convection this afternoon
and any showers/storms diminishing with nightfall. A similar set-up
is forecast on Monday, with the shortwave trough pushing through the
region overnight. With the arrival of the shortwave PWATs are
forecast to drop even lower, with some guidance showing values as
low as 1.5 inches. The bigger story with Monday's forecast will be
the hot temperatures.
High pressure will build into the forecast area on Monday aloft,
centered over the Deep South. At the surface high pressure will
briefly build into the region ahead of an approaching front.
Guidance points to high temperatures reaching into the upper 90s
across most of the forecast area. The 850mb temperatures are
forecast to reach as high as 18-20C, which would point to high
temperatures in the mid 90s. Surface winds are forecast to shift to
the NW on Monday. This direction typically leads to some downsloping
influences and drier/warmer conditions over the local forecast area.
These temperatures could potentially be record breaking at the local
climate sites. See the Climate Section for more details.
KEY MESSAGE 2: Cooler and drier conditions expected Tuesday through
mid week.
A backdoor cold front will drop through the area Monday night,
followed by seasonally strong high pressure ridging south into the
Carolinas and Georgia for midweek. This will bring temperatures down
to more typical September levels, with highs largely in the 85-90
range. Lows are expected to fall well into the 60s over most inland
locations.
The chance for rainfall should be pretty limited during this time
period as PWats are forecast to eventually drop below 1 inch (which
is 10-15th percentile of climo). The exception would be on Tuesday
across portions of southeast Georgia where low level convergence
intersects some lingering deep moisture before the drier air really
arrives. Otherwise, it looks to be a pleasant couple of days.
Northeast winds could get a bit gusty along the coast.
KEY MESSAGE 3: Minor coastal flooding possible with the Tuesday
midday high tide along the Charleston and Colleton county
coasts.
Minor coastal flooding is possible with the Tuesday midday high tide
along the Charleston and Colleton County coasts. Strengthening
northeast winds are expected on Tuesday which will increase tidal
departures. The tide would need ~1 ft departure to reach minor
flooding thresholds of 7 ft MLLW in the Charleston Harbor. Most
guidance indicates this could be achieved, with tide levels possibly
falling somewhere in the 7.0-7.2 ft MLLW range. A Coastal Flood
Advisory could be needed. No issues expected further south along the
lower SC and southeast GA coasts.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
Dry conditions are forecast through the 18Z TAF at KCHS/KJZI while
some VCTS are possible at KSAV through the afternoon. Confidence is
too low to include restrictions at KSAV due to showers/storms, so
have VCTS from 18 to 23Z. Skies are forecast to go SKC Monday
morning with winds tipping around to the NW.
Extended Aviation Outlook: VFR. Gusty winds are possible Tuesday
through Thursday afternoons.
&&
.MARINE...
Through Tonight: Weak troughing across inland locations have shifted
winds to the SSW. As the troughing weakens winds will tip to the W
overnight, generally in the 10 to 15 knot range. Seas will average 2
to 3 ft.
Monday through Thursday: No marine concerns on Monday. Winds and
seas will increase Tuesday as high pressure ridges south into the
region, with conditions remaining elevated into Thursday. Wind gusts
are expected to peak in the 25-30 knot range while seas build to 5-7
feet. There is a low-end chance some gusts reach near gale force
later Tuesday and again later Wednesday, particularly over the GA
waters. However, it looks marginal and short-lived with NBM
indicating probabilities for gusts over 34 knots are less than 30%.
Will continue to monitor. Pressure gradient should begin to ease on
Thursday, with conditions likely falling below advisory levels
Friday.
Rip Currents: Gusty northeast winds and increasing seas Tuesday into
midweek will lead to an elevated risk of rip currents. Latest rip
current forecast for Tuesday indicates a Moderate Risk for SC
beaches and a High Risk for GA.
&&
.CLIMATE...
Record High Temperatures
September 14:
KCHS: 94/1991
KCXM: 94/1938
KSAV: 96/1991
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...None.
&&
$$
CPM/ETM
FXUS62 KCHS 131825
AFDCHS
Area Forecast Discussion
National Weather Service Charleston SC
225 PM EDT Sun Sep 13 2026
.WHAT HAS CHANGED...
All sections updated.
&&
.KEY MESSAGES...
- 1) Limited rain chances today and Monday, with record challenging
high temperatures forecast Monday.
- 2) Cooler and drier conditions expected Tuesday through mid
week.
- 3) Minor coastal flooding possible with the Tuesday midday
high tide along the Charleston and Colleton county coasts.
&&
.DISCUSSION...
KEY MESSAGE 1: Limited rain chances today and Monday, with
record challenging high temperatures forecast Monday.
Despite a PWAT of 2.31 inches with this morning's 12Z KCHS RAOB
Sounding, conditions are forecast to dry out into the afternoon
hours as a shortwave trough advances towards the local forecast
area. This shortwave can be easily seen on the GOES mid-level water
vapor imagery, as of 17Z roughly located just to the west of
Jenkins/Screven/Allendale counties. The KCLX radar has begun to
detect isolated showers over southeastern GA. These showers are
forming just ahead of the shortwave, likely initiating with the
assistance of the sea breeze. Most model guidance from this morning
paint a rather benign picture of isolated convection this afternoon
and any showers/storms diminishing with nightfall. A similar set-up
is forecast on Monday, with the shortwave trough pushing through the
region overnight. With the arrival of the shortwave PWATs are
forecast to drop even lower, with some guidance showing values as
low as 1.5 inches. The bigger story with Monday's forecast will be
the hot temperatures.
High pressure will build into the forecast area on Monday aloft,
centered over the Deep South. At the surface high pressure will
briefly build into the region ahead of an approaching front.
Guidance points to high temperatures reaching into the upper 90s
across most of the forecast area. The 850mb temperatures are
forecast to reach as high as 18-20C, which would point to high
temperatures in the mid 90s. Surface winds are forecast to shift to
the NW on Monday. This direction typically leads to some downsloping
influences and drier/warmer conditions over the local forecast area.
These temperatures could potentially be record breaking at the local
climate sites. See the Climate Section for more details.
KEY MESSAGE 2: Cooler and drier conditions expected Tuesday through
mid week.
A backdoor cold front will drop through the area Monday night,
followed by seasonally strong high pressure ridging south into the
Carolinas and Georgia for midweek. This will bring temperatures down
to more typical September levels, with highs largely in the 85-90
range. Lows are expected to fall well into the 60s over most inland
locations.
The chance for rainfall should be pretty limited during this time
period as PWats are forecast to eventually drop below 1 inch (which
is 10-15th percentile of climo). The exception would be on Tuesday
across portions of southeast Georgia where low level convergence
intersects some lingering deep moisture before the drier air really
arrives. Otherwise, it looks to be a pleasant couple of days.
Northeast winds could get a bit gusty along the coast.
KEY MESSAGE 3: Minor coastal flooding possible with the Tuesday
midday high tide along the Charleston and Colleton county
coasts.
Minor coastal flooding is possible with the Tuesday midday high tide
along the Charleston and Colleton County coasts. Strengthening
northeast winds are expected on Tuesday which will increase tidal
departures. The tide would need ~1 ft departure to reach minor
flooding thresholds of 7 ft MLLW in the Charleston Harbor. Most
guidance indicates this could be achieved, with tide levels possibly
falling somewhere in the 7.0-7.2 ft MLLW range. A Coastal Flood
Advisory could be needed. No issues expected further south along the
lower SC and southeast GA coasts.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
Dry conditions are forecast through the 18Z TAF at KCHS/KJZI while
some VCTS are possible at KSAV through the afternoon. Confidence is
too low to include restrictions at KSAV due to showers/storms, so
have VCTS from 18 to 23Z. Skies are forecast to go SKC Monday
morning with winds tipping around to the NW.
Extended Aviation Outlook: VFR. Gusty winds are possible Tuesday
through Thursday afternoons.
&&
.MARINE...
Through Tonight: Weak troughing across inland locations have shifted
winds to the SSW. As the troughing weakens winds will tip to the W
overnight, generally in the 10 to 15 knot range. Seas will average 2
to 3 ft.
Monday through Thursday: No marine concerns on Monday. Winds and
seas will increase Tuesday as high pressure ridges south into the
region, with conditions remaining elevated into Thursday. Wind gusts
are expected to peak in the 25-30 knot range while seas build to 5-7
feet. There is a low-end chance some gusts reach near gale force
later Tuesday and again later Wednesday, particularly over the GA
waters. However, it looks marginal and short-lived with NBM
indicating probabilities for gusts over 34 knots are less than 30%.
Will continue to monitor. Pressure gradient should begin to ease on
Thursday, with conditions likely falling below advisory levels
Friday.
Rip Currents: Gusty northeast winds and increasing seas Tuesday into
midweek will lead to an elevated risk of rip currents. Latest rip
current forecast for Tuesday indicates a Moderate Risk for SC
beaches and a High Risk for GA.
&&
.CLIMATE...
Record High Temperatures
September 14:
KCHS: 94/1991
KCXM: 94/1938
KSAV: 96/1991
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...None.
&&
$$
CPM/ETM
Office: CAE
FXUS62 KCAE 131719
AFDCAE
Area Forecast Discussion
National Weather Service Columbia SC
119 PM EDT Sun Sep 13 2026
.WHAT HAS CHANGED...
Updated Aviation Discussion for 18Z TAFs.
&&
.KEY MESSAGES...
- 1. Above normal temps expected through Monday, with a backdoor
front ushering in drier and slightly cooler air through the
middle of next week.
&&
.DISCUSSION...
KEY MESSAGE 1: Above normal temps expected through Monday, with
a backdoor front ushering in drier and slightly cooler air
through the middle of next week.
Not much change in the forecast thinking, with Sunday being a
transition day aloft as broad mid-level trough shifts east and
ridging will steadily build into Monday. The pattern will then
steadily amplify as persistent troughing across the western
CONUS will yield strong downstream height rises across the
southeastern CONUS, resulting in one of the stronger 500 hPa
ridges on record for this time of year based on the NAEFS climo.
While this would typically suggest potentially record high
temps, a stout shortwave is expected to round the ridge into the
northeastern CONUS Monday, with associated strong convergence.
This convergence is forecast to usher in a strong surface high
pressure system into the Northeast, driving ridging lee of the
Appalachians through mid-week. As this ridging digs southward it
will manifest as backdoor surface front will some denser,
cooler & drier air pushing in from the northeast and bringing
near normal highs & below normal dewpoints and PWs by Tuesday.
Ahead of this backdoor front however, Monday will be quite warm,
with highs forecast in the mid 90s. But Tuesday-Thursday should
feature highs in the upper 80s to lower 90s, dewpoints in the
low 60s during the afternoons or upper 50's, and overnight lows
in the mid 60s. Southerly component flow and broad scale
moisture returns by late week with increased precip chances
along with it.
&&
.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
VFR conditions are expected through the TAF period.
FEW to SCT cumulus are developing this afternoon with westerly
winds around 5-8 kts. VFR conditions likely continue through the
remainder of the day where a spotty shower cannot be ruled out
near AGS/DNL, but impacts are unlikely. Overnight, a few passing
cirrus could be seen as light and variable to calm winds
develop. Slightly drier air is expected to push in, bringing
lower chances for morning restrictions, as seen in the latest
HREF, HRRR, and LAMP guidance. Cannot rule out a few patches of
fog or stratus early Monday morning mainly in portions of the
CSRA and southeastern Midlands, but confidence in impacts to the
TAF sites is fairly low. Winds Monday morning shift a bit more
northerly to northeasterly as VFR conditions likely continue
through the end of the TAF period.
EXTENDED AVIATION OUTLOOK...Rain unlikely for much of the week
but there will still be some potential for early morning
fog/stratus persists at least through Tuesday.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...None.
GA...None.
&&
$$
DISCUSSION...42
AVIATION...DH
Office: GSP
FXUS62 KGSP 131846
AFDGSP
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
246 PM EDT Sun Sep 13 2026
.WHAT HAS CHANGED...
The forecast has trended a bit drier for the first half of the week.
&&
.KEY MESSAGES...
1. Our area should remain mostly dry through the first half of
the week. Diurnal shower and thunderstorm chances increase for
the latter half of the week with temperatures remaining above
normal for mid-September.
&&
.DISCUSSION...
Key message 1: Our area should remain mostly dry through the first half
of the week. Diurnal shower and thunderstorm chances increase for the
latter half of the week with temperatures remaining above normal for
mid-September.
In the wake of a weak frontal passage, we could see a few showers
and maybe an isolated thunderstorm or two this afternoon/evening.
Otherwise, the weather should be mostly quiet with temperatures
roughly 3 to 6 degrees above normal.
A stout upper shortwave is expected to pass to our north on Monday,
helping to push a back door cold front southward across our area.
The model guidance continues to show little in the way of response
wrt the fropa. This makes sense given the weak cap and minimal CAPE
across the region Monday afternoon/evening as it moves through. On
Tuesday, broad upper ridging spreads over the Southeast from the west
and persists thru mid-week. The upper ridge will help support sfc
high pressure that migrates eastward from the lower Great Lakes to
New England from late Monday through Tuesday. On Wednesday, the sfc
high gets pushed off the New England Coast by robust low pressure
tracking across eastern Canada. Brief, weak cold air damming tries
to develop on Tuesday, however a lack of moisture in the light ELY
low-level flow will likely produce little in the way of precipitation.
In addition, the expected lack of persistent cloud cover thru the day
should allow high temperatures to top-out near, if not a few degrees
above normal. If better cloud cover lingers for longer, fcst tempera-
tures could be too warm. For the second half of the week, a frontal
boundary stalls just to our north while a weak surface low tries to
develop somewhere off the coast of south Florida. At present, the
deeper moisture associated with the frontal bndy appears to remain
mostly over the mtns each day, suggesting a chance of diurnal showers
and storms each day Thursday thru Saturday with temperatures remaining
1 to 2 categories above normal for mid-September.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
At KCLT and elsewhere: Expect mostly dry, VFR conditions to prevail
thru the 18z TAF period. Most of the latest guidance suggests another
round of mtn valley fog and low stratus overnight, but it's unclear
whether it will reach KAVL. Winds will favor a NWLY direction at KAVL
overnight, but they will be weak and could be more VRB at times. For
the time being, I have 5sm visby from 10 to 13z at KAVL. Otherwise,
expect mostly few high clouds thru the period with winds becoming
light and VRB (or at times favoring a NW direction) at most sites
later tonight. Winds will pick up from the N/NE tomorrow afternoon
with speeds in the 5 to 10 mph range. KAVL will likely see some low-
end gusts thru the early evening with winds becoming light later
tonight. Winds at KAVL will favor a NW direction tomorrow.
Outlook: Mostly dry conditions are expected to persist through the
middle of the week. Shower chances and their associated restrictions
increase later in the week.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...None.
NC...None.
SC...None.
&&
$$
JPT
