Area Forecast Discussion
Issued by NWS Charleston, SC

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637
FXUS62 KCHS 142323
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
723 PM EDT Mon Jul 14 2025

.SYNOPSIS...
Atlantic high pressure will prevail into the upcoming weekend.

&&

.NEAR TERM /THROUGH TUESDAY/...
SPC mesoanalysis indicates that the CWA has CIN values between
50-75 J/kg following widespread thunderstorms this afternoon
and evening. Isolated to scattered showers and thunderstorms may
develop along newer outflow boundaries until late this evening.
The rest of the night should remain dry. The forecast update
will align hourly temperatures with recent observations, showing
large areas of rain-cooled temps in the mid 70s.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...
Tuesday: A weakening TUTT will be approaching Florida with dry
air located on the northwest flank. PWATs drop to less than
1.5", with 2"+ PWATs on either side. Surface convergence from
Monday will have moved further inland over GA on Tuesday with a
sea breeze forecast to move inland during the afternoon. The
lower PWAT air will likely limit convection slightly, but the
overall extent of coverage should still be at least chance. High
temperatures will also be lower on Tuesday as 1000/ 850 mb
thicknesses fall to 1415 m (or about 10 m cooler than Monday)
due to the undercutting TUTT.

Wednesday - Thursday: Another TUTT will break off and approach the
region Wednesday allowing thunderstorms to continue both days. Storm
motions Wednesday are forecast to be around 10 kt, but increase to
near 20 kt by Thursday as the TUTT moves overhead and elongates the
wind field slightly. This means the greatest chance for locally
heavy rainfall will be on Wednesday, with slightly lower chances on
Thursday due to increased storm motion. High temperatures will be
near climo or in the lower 90s.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
The TUTT that was near the area on Thursday will cross Florida
Saturday keeping afternoon thunderstorm chances in the forecast
through the weekend. High temperatures will also remain near
climo/ slightly above climo as low level thicknesses slowly
recover. Max heat index values each afternoon will be near or
just below advisory criteria (108 F).

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
Prior to the 0Z TAFs, a few remnant showers were drifting around
KSAV, with little to no impact expected. These showers should
dissipate by 1Z. The rest of the night, terminals should remain
dry with light winds. Sea breeze convection is forecast to
develop across KCHS and KJZI between 16-19Z. The KCHS and KJZI
TAFs will feature TEMPOs to highlight -TSRA, restricting
visibility to MVFR. Coverage around KSAV appears too low to
mention of this time.

Extended Aviation Outlook (Tuesday through Saturday): VFR will
mainly prevail throughout the period, however brief flight
restrictions are possible within showers and thunderstorms that
develop in the afternoon and/or evening hours.

&&

.MARINE...
This Afternoon and Tonight: Expect generally northeast to east-
northeast flow at 5 to 10 kt to prevail through tonight. This flow
pattern will generally be driven by the circulation around the
developing low pressure off the Florida coastline. It could become a
bit gusty in the afternoon with gusts up to 15 to 20 kt as the
seabreeze pushes inland (gusts strongest across the immediate
coastline and the Charleston Harbor). Southeasterly swell will
continue to mix into the local waters and seas will be 1 to 2
ft. Showers and thunderstorms will develop over the coastal
waters tonight and increase in coverage closer to daybreak.
Otherwise, no marine concerns expected.

Tuesday through Saturday: A TUTT will be located just off of the SC
coast through the extended while at the surface Bermuda high
pressure will be in control. For the marine zones, this will
translate to each afternoon featuring wind gusts peaking 15 to 20 kt
due to an inland advancing sea breeze. Seas through the period will
be 2-4 ft.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...None.

&&

$$

NEAR TERM...NED
SHORT TERM...Haines
LONG TERM...Haines
AVIATION...NED
MARINE...Dennis/Haines