AFD_CHS

FXUS62 KCHS 032318 AFDCHS

Area Forecast Discussion National Weather Service Charleston SC 618 PM EST Tue Mar 3 2026

.WHAT HAS CHANGED...

All sections updated.

.KEY MESSAGES...

- 1) Areas of fog expected across portions of southeast Georgia

and the South Carolina Lowcountry and adjacent waters tonight into Wednesday morning.

- 2) Unseasonably warm temperatures are expected through the

weekend.

.DISCUSSION...

KEY MESSAGE 1: Areas of fog expected across portions of southeast Georgia and the South Carolina Lowcountry and adjacent waters tonight into Wednesday morning.

Satellite imagery shows that an area of dense fog is already ongoing across the GA coastal waters and likely starting to push onshore along the McIntosh County coast. Current thinking is that dense fog across the coastal waters will gradually expand inland along the coast later this evening and then spread across the entire area through the night. Dense fog looks likely, and a Dense Fog Advisory will probably eventually be needed for most or all of the area. Fog will stick around through at least mid morning on Wednesday and likely not completely improve until late morning or midday.

KEY MESSAGE 2: Unseasonably warm temperatures are expected through the weekend.

The mid-levels will consist of broad ridging over the Gulf coast states Wednesday morning. It'll shift over the Southeast U.S. Wednesday afternoon, then offshore on Thursday, where it'll prevail through Saturday. The ridge is then expected to shift further offshore early next week, causing heights to lower over our region. At the surface, High pressure will prevail in the western Atlantic Wednesday through the weekend. This will usher some moisture into our region. Wednesday and Thursday should be dry, while POPs are slight chance across our far inland counties Friday afternoon and Saturday afternoon. POPs appear to trend a bit higher Sunday afternoon and Monday afternoon. But no severe thunderstorms are expected.

What will be noticeable is the unseasonably warm temperatures. High temperatures Wednesday will range from the mid to upper 70s across our SC counties to the upper 70s to lower 80s across our GA counties, except cooler at/near all of our beaches. High temperatures Thursday should be a tad higher, from the upper 70s to near 80 degrees across our SC counties to around 80 degrees to the lower 80s across our GA counties, except cooler at/near all of our beaches. Temperatures remain well above normal Friday through early next week. Highs will range in the upper 70s to middle 80s across our SC counties and the lower to middle 80s across our GA counties. Though, it'll be cooler at/near the beaches. Low temperatures during this time period will be in the upper 50s to lower 60s. Despite these temperatures, no records are currently forecasted to be tied or broken.

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...

The 00z TAF period begins with VFR conditions at KCHS, KJZI, and KSAV. The primary forecast challenge will be dense fog and very low ceilings expected to begin developing later this evening. Current thinking is that marine dense fog and low stratus will gradually spread inland later this evening and through the overnight. Widespread IFR conditions, with dense fog, are anticipated and reflected in the TAF's. Full improvement back to VFR likely won't occur late morning or midday on Wednesday.

Extended Aviation Outlook: Restrictive ceilings are possible overnight into the early morning hours each night through the end of the week due to low stratus/fog.

.MARINE...

Early evening update: Satellite imagery shows a large area of dense fog and low stratus across both the nearshore and outer GA waters. Therefore, we have issued a Dense Fog Advisory that runs through noon Wednesday.

High pressure across the region will result in calm winds overnight. Moisture below a persistent llvl inversion should result in low stratus to develop this evening, spreading from the coast. Dewpoints across the marine zones in the mid to upper 50s across shelf waters in the low to mid 50s will favor sea fog formation. Recent runs of the HRRR indicate that sfc condensation pressure deficits fall to around 0 mb late tonight into daybreak Wednesday. HREF shows the probability of less than 0.5 mile visibility across the region remains around 50 percent along the coast to 40 percent inland. Dense Fog Advisories may needed for the marine zones tonight into Wednesday morning.

High pressure will prevail in the western Atlantic midweek through the weekend. This will cause surface winds to shift to the east by Wednesday, then the southeast Wednesday night into Saturday. Winds should veer to the south/southwest early next week, which would increase the potential for sea fog. Otherwise, winds and seas will stay below Small Craft Advisory levels.

.CHS WATCHES/WARNINGS/ADVISORIES...

GA...None. SC...None. MARINE...Dense Fog Advisory until noon EST Wednesday for AMZ354-374.

BSH