435
FXUS62 KCHS 140703
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
303 AM EDT Fri Aug 14 2026

.WHAT HAS CHANGED...
All sections have been updated.

&&

.KEY MESSAGES...
- 1) Heat will remain a concern into the middle of next week.

- 2) Strong to severe thunderstorms are possible each afternoon
  through the weekend.

&&

.DISCUSSION...
KEY MESSAGE 1: Heat will remain a concern into the middle of next
week.

Today and Saturday: A warm pattern will remain in place with a large-
scale ridge across much of the Deep South and Southeast United
States through the weekend. Ample sunshine will promote strong sfc
heating in advance of afternoon convection each day, with 1000-850mb
thickness values supportive of afternoon highs in the mid-upper 90s,
with a few locations potentially touching 100 degrees away from the
coast, which could result in some record warmth (see Climate Section
below). In addition to hot temperatures, conditions will remain
humid with sfc dewpts in the mid-upper 70s each day. A west-
northwest downsloping wind should result in a slightly delayed
seabreeze the next few afternoons, promoting some mixing out of sfc
dewpts inland, but moisture pooling along/near the sea breeze
will eventually shift higher moisture content onshore each day
for at least a few hours as well. This will likely result in
the higher heat/moisture combination along coastal zones (along/east
of I-95) for the next couple days, with heat index values up to
the 110-115 range late morning into the afternoon and again on
Saturday. Given the setup and expected heat index values, an
Extreme Heat Warning remains in effect for coastal counties from
11 AM to 8 PM today while remaining areas are included in a Heat
Advisory for the same time period. The slightly more favorable
position of the synoptic ridge supports slightly higher heat
index values along the coastal corridor Saturday, especially if
convection holds off longer than anticipated mid-late afternoon.
Therefore, an Extreme Heat Watch has been issued for all Southeast
SC/GA coastal zones from 11 AM to 8 PM Saturday. Another Heat
Advisory could be needed for inland areas on Saturday as well.

Early to Middle of Next Week: Hot/humid conditions likely remain
across the Southeast United States late weekend into the middle of
next week with the large-scale ridge centered over or nearby,
although a front could lead to greater shower/thunderstorm coverage
that limits maximum heat conditions Sunday. Record warmth is
possible next week with guidance suggesting several areas of
100+ temps Monday/Tuesday and little to no shower/thunderstorm
activity. Additional heat headlines are likely early into the
middle of next week.


KEY MESSAGE 2: Strong to severe thunderstorms are possible each
afternoon through the weekend.

The heat and humidity (mentioned in Key Message 1) will provide a
moderate amount of instability across our area each afternoon
through the weekend. Depending on the model, SBCAPE values peak in
the 2,000-2,500 J/kg range, with DCAPE values upwards of 800 J/kg.
There are some minor differences amongst the various near- term CAMS
and even the synoptic models. But the general consensus is that
there should be isolated to scattered convection each afternoon
through the weekend. These details will need to be refined with each
forecast. But the storms are most likely to start along the sea
breeze and then shift inland, with outflow and boundary interactions
playing a role in storm formation and persistence. Given the
aforementioned instability, strong to severe thunderstorms are
possible. The main threat would be damaging winds. But heavy
rainfall is also a concern due to weak steering flow. Backbuilding
and/or training of storms could drop enough rainfall to generate
very localized flooding. The convection each afternoon is expected
to dissipate each evening.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
VFR conditions are expected at CHS/JZI/SAV terminals through at
least 18Z Friday. The risk for isolated to scattered showers and/or
thunderstorms increases during afternoon into early evening hours at
all terminals. PROB30 groups for thunderstorms and MVFR conditions
remain in place for CHS/SAV between 19-24Z Friday and for JZI
between 18-23Z Friday. Gusty winds could also accompany thunderstorms.
VFR conditions are then expected to prevail at all terminals
between 02-06Z Saturday.

Extended Aviation Outlook: Afternoon showers and thunderstorms will
bring brief flight restrictions through the weekend.

&&

.MARINE...
Today and Tonight: Conditions are expected to remain quiet across
local waters between the western periphery of an Atlantic high and
weak troughing inland, although thunderstorms that develop over land
could shift offshore late afternoon into early evening hours. A few
thunderstorms could remain strong when shifting across coastal
areas. Outside thunderstorms, southwesterly winds around 10 kt this
morning should turn more southerly and gust up to 15-20 kt this
afternoon, then persist into evening hours, before slowly weakening
and returning to a southwesterly direction overnight. Seas should be
no larger than 2-3 ft.

Extended Marine: There will be areas of High pressure in the western
Atlantic and the northern Gulf, while surface troughing will be over
the Southeast U.S. The interaction between all of these synoptic
features will generate a typical summertime wind pattern. Winds
will generally be from the SW, backing a bit each day and veering
some each night. The strongest winds should be during the day,
especially closer to the coast due to the sea breeze. Seas will
mainly be in the 2-3 ft range.

&&

.CLIMATE...
Record High Temperatures:

August 14:
KCHS: 102/1995
KSAV: 102/1925

August 15:
KCHS: 96/2023
KCXM: 99/1918
KSAV: 100/1918

August 16:
KCHS: 99/1954
KSAV: 100/1954

August 17:
KCHS: 102/1954
KSAV: 102/1954

August 18:
KCXM: 97/1995
KSAV: 100/1995

Record High Minimum Temperatures:

August 14:
KCHS: 80/2023
KCXM: 83/2023
KSAV: 80/2023

August 15:
KCHS: 78/1995
KCXM: 83/2021
KSAV: 80/1995

August 16:
KCHS: 78/2019
KCXM: 83/2016
KSAV: 78/2019

August 17:
KCHS: 80/2017
KCXM: 83/2017
KSAV: 78/2017

August 18:
KCHS: 80/2017
KCXM: 82/2017
KSAV: 78/2010

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...Heat Advisory until 8 PM EDT this evening for GAZ087-088-
     099>101-114-115-137.
     Extreme Heat Warning until 8 PM EDT this evening for
     GAZ216>219-238>241.
     Extreme Heat Watch from Saturday morning through Saturday
     evening for GAZ216>219-238>241.
SC...Heat Advisory until 8 PM EDT this evening for SCZ040-042>044.
     Extreme Heat Warning until 8 PM EDT this evening for SCZ045-
     147>152.
     Extreme Heat Watch from Saturday morning through Saturday
     evening for SCZ045-147>152.
MARINE...None.

&&

$$