Charleston, SC 29409 Weather

What has changed

Aviation section has been updated.

Key messages

- 1) A multi-day coastal flooding event will slowly diminish through the remainder of this week.

- 2) Sustained northeast winds will lead to a High Risk for rip currents along our South Carolina and Georgia beaches through Thursday.

- 3) Dry and warming conditions will continue through the week before rain chances increase late weekend.

Discussion

.KEY MESSAGE 1: A multi-day coastal flooding event will slowly diminish through the remainder of this week.

The full moon was on 10/26, while the lunar perigee will today leading to a similar astronomical tide as yesterday. Astronomical tides will begin to trend lower the rest of this week as we move past the lunar perigee, with the morning/early afternoon high tide being the higher of the two tide cycles. Additionally, northeasterly winds are expected to gradually ease, especially towards the end of this week. This will also cause tidal departures to lower.

Charleston Tide Gauge: Moderate coastal flooding is forecasted with the Wednesday and Thursday morning high tide cycles, followed by minor coastal flooding Friday, and maybe even Saturday. Coastal Flood Advisories will be needed.

Fort Pulaski Tide Gauge: Minor coastal flooding is forecasted with the Wednesday morning high tide. A Coastal Flood Advisory will be needed.

KEY MESSAGE 2: Sustained northeast winds will maintain a High Risk of rip currents along our South Carolina and Georgia beaches through Thursday.

The combination of sustained, gusty northeast winds, persistent long- period swell, and continuous wave action will support dangerous rip currents along our beaches. A High Risk for rip currents is in place for all area beaches through Thursday, driven by 5+ ft swells every 8-9 seconds. An enhanced risk will likely continue through Saturday, October 31, which marks the end of the 2026 surf season and the final routine issuance of the Surf Zone Forecast.

KEY MESSAGE 3: Dry and warming conditions will continue through the week before rain chances increase late weekend.

High pressure will begin to slowly breakdown and drift over the Carolinas as we head into the second half of the week. The high pressure at the surface and the upper- level ridging will yield a dry forecast through the remainder of the week. Temperatures will steadily warm into the weekend, with highs pushing 80 away from the coastline by Friday. Overnight lows initially in the 50s will warm into the 60s.

By the weekend, A rather drastic shift in the synoptic pattern is expected this as the high pressure breaks down and a shortwave trough aloft pivots across the Southeast/Mid- Atlantic states this weekend. Rain/thunderstorm chances will increase this weekend and into early next week associated with this upper level feature. A couple more systems will likely arrive by the middle part of next week bringing increased rain chances through most of next week.

Aviation

12Z TAFs: Light north-northeasterly flow should continue this morning with VFR conditions prevailing. Some lowered ceilings have moved into coastal South Carolina this morning but confidence is not high enough to support lowered ceilings at CHS this morning. Northeasterly winds should increase this afternoon with gusts to around 20 knots possible. Expect winds to ease back after 20-21Z. Lowered ceilings may arrive early Thursday morning mainly along and east of I-95. MVFR ceilings could impact all local TAF sites with some light ground fog west of I-95 around 12Z Thursday.

Extended Aviation Outlook: Gusty north-northeast winds are expected over the weekend at KCHS, KJZI, and KSAV, primarily during the afternoon hours.

Marine

Wednesday through Thursday: A persistent inland wedge of high pressure will maintain elevated northeast winds and seas, with little improvement through Thursday night. Small Craft Advisories remain in effect for all nearshore waters out 20 nm (excluding Charleston Harbor) and the offshore GA waters out 60 nm. Expect north-northeast wind gusts of 25 to 30 kt, nearshore seas of 5 to 8 ft, and offshore seas of 8 to 10 ft (highest across Georgia waters).

Friday through Monday: Conditions will improve markedly on Friday as the pressure gradient relaxes, bringing an end to the prolonged Small Craft Advisories (all with the exception of the outer GA waters). However, improvement will be short-lived. A broad area of low pressure developing over the Southeast U.S. will tighten the gradient once again over the weekend, driving gusts back up to 25 to 30 kt and building seas back above 6 ft. Another round of Small Craft Advisories could be needed Saturday afternoon through the remainder of the weekend and potentially into Monday.

Watches, warnings and advisories

GA: High Risk for Rip Currents through this evening for GAZ217-219-239- 241. Coastal Flood Advisory until noon EDT today for GAZ217-219-239- 241. SC: High Risk for Rip Currents through this evening for SCZ148>151. Coastal Flood Advisory until noon EDT today for SCZ148>151. MARINE: Small Craft Advisory until 8 AM EDT Friday for AMZ360-362. Small Craft Advisory until 8 PM EDT Friday for AMZ364. Small Craft Advisory until 7 PM EDT Monday for AMZ384.