National Weather Service Raw Text Product

784 
FXUS62 KCHS 121112
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
712 AM EDT Thu Jun 12 2025

.SYNOPSIS...
A series of upper level disturbances will affect the area
through the weekend while high pressure remains offshore. 

&&

.NEAR TERM /THROUGH TONIGHT/...
Today: Aloft, ridging will continue to be centered from just 
off the east coast of FL and extending into the forecast area 
and the Southeast. At the surface, the subtropical high over the
Atlantic will drive the summer-like pattern as it extends back 
to the west and into the area. The morning will start off with 
isolated to scattered coastal showers from the GA coast up
through Beaufort County. These showers will be developing 
within subtle convergence boundaries that show up on radar and
could spread up into the Charleston area as well. These showers
will move relatively slow to the northeast within the weak 
steering flow, and could drop a few hundredths of an inch of 
rainfall. This activity should dissipate by mid morning and 
attention will then turn to afternoon convection. Convection 
should start developing along the sea breeze in the early 
afternoon and gradually shift inland into the evening. Overall, 
the best coverage is expected inland of the coast especially by 
late afternoon and the evening. Model soundings aren't 
particularly impressive showing little to no shear and weak 
DCAPE values. MLCAPE looks to be in the 1,000-1,500 J/kg range. 
The overall severe threat is quite low, but we could still see a
strong to marginally isolated severe storm where boundary 
interactions can work to enhance updrafts. Storm motion will be 
very slow, on the order of 5-10 knots. This means there will be 
a threat of locally heavy rainfall and possibly a few instances 
of minor flooding. Temperatures are forecast to reach the low 
90s in most places. 

This evening and tonight: Afternoon convection should shift 
inland through the evening and we should be pretty much 
convection-free by the late evening. Overnight, we will see the 
focus for showers and thunderstorms shift to the SC coast and 
the adjacent coastal waters. There are no significant concerns 
for fog at this time. Lows are forecast to fall into the low to 
mid 70s.

&&

.SHORT TERM /FRIDAY THROUGH SUNDAY/...
The forecast area will remain on the backside of high pressure 
at the surface and aloft late week into the weekend. Diurnally-
driven showers and thunderstorms will be possible each day, with
coverage highest in the afternoon and evening. Shortwave energy
rotating through the region at times could provide additional 
focus for convective development. Organized severe weather is 
not expected, but a couple stronger storms are possible, as is 
typical for this time of year. Highs will be seasonable in the 
upper 80s to around 90, but heat indices will likely exceed 
triple digits in many spots over the weekend. Values are held 
below Heat Advisory criteria. Lows will be in the 70-75 range, 
except a bit higher at the beaches.

&&

.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
Ridging will persist during the early to middle of next week, 
with a shortwave trough to pass by to the north early in the 
period. The surface will feature high pressure offshore and a 
trough of low pressure inland. Scattered showers and 
thunderstorms will be possible each day, especially during peak 
heating. Temperatures will be warming, and combined with higher 
humidity, heat indices are currently forecast to approach or 
exceed 105F, possibly even close to Heat Advisory criteria of 
108F in spots.

&&

.AVIATION /11Z THURSDAY THROUGH MONDAY/...
The 12z TAF period begins with VFR conditions at KCHS, KJZI, 
and KSAV. Coastal showers are developing this morning and could
shift into the vicinity of the terminals over the next few
hours. We have included VCSH at KSAV from 12-15z, and at KCHS
and KJZI starting at 15z. It is possible these showers could
produce brief rainfall and perhaps MVFR ceilings, but the
chances of direct impacts are low. For afternoon and evening 
thunderstorm chances, model guidance suggests the best chances 
will be inland of the TAF sites. Therefore, we have not included
any mention of thunder in the TAF's. 

Extended Aviation Forecast: Brief flight restrictions are 
possible in showers and thunderstorms each day, mainly in the 
afternoon.

&&

.MARINE...
Today and tonight: High pressure to the east in the Atlantic 
will drive southerly onshore flow across the local waters 
through the period. Wind speeds should top out around 15 knots 
this afternoon and evening along the land/sea interface with the
sea breeze. Seas are forecast to average 2-3 feet. 

Friday through Tuesday: Marine conditions are expected to stay 
below Small Craft Advisory criteria through the period. 
Southerly flow will persist with speeds 15 knots or less. Seas 
will average 2-3 feet, with some occasional 4 footers in the 
outer portions of the waters.

&&

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

&&

$$

NEAR TERM...BSH
SHORT TERM...ETM
LONG TERM...ETM
AVIATION...BSH/ETM
MARINE...BSH/ETM