934
FXUS62 KCHS 051511
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
1111 AM EDT Fri Jul 5 2024

.SYNOPSIS...
High pressure will persist through Friday, then a weak cold
front will stall over the area this weekend and linger through
the middle of next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 11 AM: Latest round of observations indicated that many
areas have warmed to around 90 degrees with dewpoints between 75
and 80 degrees. Visible satellite indicated a well-defined land
breeze across the outer SC/GA waters, advancing to the east.
Over land, a field of fair-weather cumulus clouds have develop
across most of the forecast area, conditions appears mostly to
partly sunny. Recent runs of the HRRR indicate that the sea
breeze will develop along the coast by 1 PM, slowly pushing
inland through the rest of the afternoon. Forecast soundings
west of the sea breeze indicates that late afternoon mixing may
reach between 5-6 kft. The deep mixing should reduce afternoon
dewpoints, however, values should remain in the mid 70s. High
temperatures are forecast to range from the upper 90s inland to
the mid 90s along the coast. The combination of the hot
temperatures and elevated dewpoints, inland counties should see
at least a couple of hours of heat index values at or above 108
degrees this afternoon. A Heat Advisory has been issued for many
counties until 8 PM this evening. Given a convective temperature
in the mid 90s, isolated to scattered showers and thunderstorms
are possible late this afternoon and evening across SE GA.

Tonight: Any convection that has developed and/or drifted across far
inland zones should struggle to persist given a loss of diurnal
heating and weak shear in place. Those that do persist, could last
an hour or two post sunset, mainly due to outflow boundary
interactions. The rest of the night will remain rather quiet, but
mild ahead of a front approaching from the northwest this weekend.
In general, lows should range in the mid-upper 70s inland to lower
80s at the beaches.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY/...
The upper ridge will be centered over northern Florida on
Saturday while a weak shortwave rotates around the northern
periphery during the afternoon. A weak cold front is forecast to
drop southeast into the area during the day, then stall nearby
through early next week. The greatest moisture and instability
will be across inland areas on Saturday which is where we show
the greatest coverage of showers and thunderstorms. High temps
in the mid 90s with mid/upper 70s dewpoints will produce heat
indices 105-110F for several hours during the afternoon in most
locations. Dewpoints could mix out just enough far inland to
keep heat indices below 105 in those areas. A Heat Advisory will
likely be needed for much of the area.

Additional shortwaves moving in from the west Sunday and Monday
will break down the upper ridge, reducing high temps by a couple
degrees. The deep moisture is expected to expand eastward, with
the entire area under at least 2.1" PWATs. Considerable
coverage of showers/tstms expected both days.

&&

.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
A fairly wet pattern likely to persist for much of next week due
to deep tropical moisture in place, continual shortwaves, and a
weak convergence axis along the decaying cold front. The
greatest coverage should be during the afternoon and evening
hours. Wednesday looks like the hottest day during this period,
with the potential for Heat Advisories.

&&

.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
VFR conditions are expected to prevail at CHS/JZI/SAV terminals
through 12Z Saturday.

Extended Aviation Outlook: Brief flight restrictions are possible in
showers and thunderstorms, mainly in the afternoon and evenings,
this weekend through the middle of next week.

&&

.MARINE...
Today and Tonight: After some nocturnal surging weakens early this
morning, high pressure extending across local waters from the
northeast along with lee troughing taking place well inland should
favor a modest pressure gradient across local waters. In general,
southwest winds will turn more south-southeast this afternoon,
peaking around 15 kt, highest near the coast where a seabreeze
develops and shifts inland. Overnight, a slightly weaker southerly
wind takes place (10-15 kt) with high pressure continuing across
local waters well in advance of the approaching front this weekend.
Seas will range between 2-3 ft through tonight.

Saturday through Wednesday, a typical summertime pattern will
persist, with prevailing southerly flow and winds/seas well
below advisory thresholds.

Rip Currents: A swell of 2 feet every 10 seconds and proximity to
the new moon will maintain a Moderate Risk for rip currents for
all beaches today, and likely through Saturday due to lingering
2-3 feet swell every 9 seconds and onshore winds.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...Heat Advisory until 8 PM EDT this evening for GAZ087-088-099-
     100-114-115.
SC...Heat Advisory until 8 PM EDT this evening for SCZ040-042>045-
     052.
MARINE...None.

&&

$$

NEAR TERM...NED
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...DPB/JRL
MARINE...DPB/JRL