540
FXUS62 KCHS 020606
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
206 AM EDT Tue Jul 2 2024

.SYNOPSIS...
A cold front will impact the area tonight into early Tuesday
before dissipating offshore. A hot and humid air mass will
build over the region during the latter half of the week. By
Monday, a weak cold front may reach coastal Georgia and South
Carolina.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
Tonight: Sfc analysis continues to show a front currently draped
east to west across the local area, from the South Carolina coastal
waters through the Beaufort, SC area and inland just south of the
Metter, GA. The environment remains very moist along and south of
the feature (PWATs around 2.2 inches), suggesting showers and
thunderstorms continuing for a few more hours near the front where
moisture convergence is enhanced. Moderate to isolated heavy
rainfall is possible, especially near the coast where an onshore
flow continues to advect ample moisture over land near the front.
Here an additional 1-3 inches of rainfall is possible tonight.
Latest radar trends are also suggesting some development of
showers and thunderstorms along the southeast Georgia coast,
shifting north within a light southerly flow and potentially
impacting the Savannah Metro given the front will be slow to
make further southward progress overnight. Overnight lows will
be slightly cooler than the previous night, particularly north
of the front. In general, low temps should range between the
upper 60s/lower 70s well inland and north to mid 70s across
southeast Georgia. Temps should remain in the upper 70s near the
Georgia beaches.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY/...
Tuesday: The surface pattern is expected to feature a stalled
boundary across SE GA with drier high pressure ridging across
the SC Lowcountry. The environment along and south of the front
should continue to feature deep instability and PW. The forecast
will feature scattered to numerous showers and thunderstorms
along and south of the front, keeping portions of inland SC dry.
Using a blend of MOS, high temperatures are forecast to range
in the mid to upper 80s.

Wednesday: Short term guidance indicates that a 595 dm ridge
will build over the Deep South and Southeast CONUS. At the sfc,
the center of high pressure will remain off the NE and middle
Atlantic states, resulting in ENE flow across the forecast area.
This pattern will support a sea breeze to develop, serving as a
focus for deep convection. Given the wide field of instability,
scattered to numerous showers and thunderstorms are forecast to
develop along the sea breeze. High temperatures are forecast to
range around 90 degrees. A few counties across extreme SE GA
may see heat index values peak between 100-105 degrees.

Independence Day: Mid-level ridge will build over the forecast
area on Thursday. Given high pressure over the western Atlantic,
a sea breeze may develop during the afternoon. However, GFS
forecast soundings indicate drier conditions compared to the
first half of the week. Forecast soundings indicate PW around
1.5 inches with an inversion centered at H65. This profile
indicates limited instability. The forecast will indicated
isolated showers and thunderstorms. High temperatures are
forecast to range between 90-95 degrees over dewpoints in the
low to mid 70s. Heat index values are forecast to peak between
100-105 degrees.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Friday through Sunday, the feature of concern will remain the
595 dm ridge over the region. The forecast area under the strong
ridge will feature high temperatures in the mid to upper 90s
each day. In addition, dewpoints will climb in the mid to upper
70s. The max heat index will range between 105 to 113 each
afternoon. This may result in either a Heat Advisory or a
Excessive Heat Warning late this week into early next week. The
forecast will indicate diurnal isolated to scattered showers and
thunderstorms each day.

On Monday, a weak front will approach from the west as the mid-
level ridge shifts over the western Atlantic. Conditions across
the forecast area will remain hot. However, storm coverage
should increase, bringing some relief from the heat.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
KCHS/KJZI: MVFR cigs will prevail through 10Z Tuesday, before
turning to VFR late morning. However, recent shower development
along the southeast South Carolina coast could drift back over the
terminals tonight, leading to reduced vsbys, and perhaps IFR
conditions before daybreak. For this reason, have started with
TEMPO MVFR vsbys as well due to showers at the JZI terminal
between 06Z-08Z Tuesday.

KSAV: Light showers will continue to impact the terminal during the
next hour or two. Regardless, MVFR cigs will prevail through at
least 13Z, before gradually returning to VFR a few hours after
daybreak. Additional showers and thunderstorms remain possible
at the terminal Tuesday afternoon with a nearby front and ample
moisture in place. TEMPO flight restrictions will likely be
needed in future TAF issuances to account for activity directly
impacting the terminal. Outside of precip, MVFR cigs look to
return by around 02Z Wednesday and could prevail through the
night.

Extended Aviation Outlook: Brief flight restrictions are
possible in showers and thunderstorms, mainly in the afternoon
and evenings through the period.

&&

.MARINE...
Tonight: A cold front will work slowly south across local
waters. Winds will shift to the northeast behind the front with
speeds reaching 15-20 kt in the South Santee-Edisto Beach
nearshore leg late. A few gusts could touch 25 kt, but the
duration and coverage are to small to justify a Small Craft
Advisory at this time. Otherwise, winds speeds will remain 15 kt
or less. Widespread showers/tstms could reduce vsbys to 1 NM or
less at times. A few strong convective wind gusts in excess of
35 kt could also occur. Seas will average 2-4 ft.

Tuesday through Saturday: Gusty ENE winds should develop across
the nearshore SC waters on Tuesday. The region will remain
between building high pressure and the front stalled to the
south. Gusts are forecast to remain around 20 kts with 3-4 ft
seas. Conditions are forecast to remain below Small Craft
Advisory criteria through the rest of the week. A weak pressure
gradient should support winds 15 knots or less and seas
averaging 2-3 ft.

&&

.CLIMATE...
Daily Rainfall Records for July 1:
KCHS: 2.66 set in 1948
KCXM: 1.64 set in 1966 (*As of 8pm, 1.93 has fallen today*)
KSAV: 2.76 set in 1871

&&

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

&&

$$

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