South Santee River to Edisto Beach, SC Marine Forecast
|Today...N Winds 15 To 20 Kt, Becoming Ne 10 To 15 Kt This Afternoon. Seas 4 To 5 Ft.|
|Tonight...Ne Winds 5 To 10 Kt. Seas 3 To 4 Ft.|
|Sat...Ne Winds 10 To 15 Kt With Gusts To 20 Kt. Seas 3 To 4 Ft.|
|Sat Night...Ne Winds 10 To 15 Kt. Seas 3 To 4 Ft.|
|Sun...Ne Winds 15 To 20 Kt. Seas 4 To 5 Ft, Building To 4 To 6 Ft In The Afternoon.|
|Sun Night...Ne Winds 10 To 15 Kt, Increasing To 15 To 20 Kt After Midnight. Seas 4 To 5 Ft.|
|Mon...Ne Winds 15 To 20 Kt. Seas 4 To 5 Ft.|
|Mon Night...Ne Winds 15 To 20 Kt. Seas 4 To 6 Ft.|
|Tue...Ne Winds 15 To 20 Kt. Seas 4 To 6 Ft.|
|Tue Night...Ne Winds 15 To 20 Kt. Seas 4 To 6 Ft. A Slight Chance Of Showers.|
| Area Forecast Discussion|
National Weather Service Charleston SC
347am EDT Fri September 29 2023
A wedge of high pressure will remain across the area into at least the middle of next week, while a broad trough of low pressure persists well offshore.
Near Term - Through Tonight
GOES-East water vapor clearly indicated a closed low centered over western PA/NY, with a trough extending south along the Atlantic coast to the northern Gulf of Mexico.Near Term - Rest Of Today Through Tonight
ance indicates that the mid-level trough will remain over the forecast area through today. At the sfc, a ridge should remain over the region this morning, then weaken this afternoon into a broad area of high pressure. This pattern should maintain a trough of 1000-850 mb thicknesses across the CWA (County Warning Area) through this afternoon. Favoring the cooler members of MOS guidance, high temperatures are forecast to range from the low to mid 80s across the CHS Tri-county to the mid 80s across SE GA. In addition, conditions will feature dry weather with generally steady northeast winds.
Tonight, the H5 pattern across the CONUS will evolve into a Omega Block by late tonight, with the ridge axis over the Mississippi River Valley. This pattern will support a broad mid-level trough across the CWA with weak surface high. Using a blend of MOS, low temperatures are forecast to range from the low 60s inland to the mid to upper 60s along the coast.
Short Term - Saturday Through Monday
Low pressure aloft centered over New England on Saturday will slowly shift eastward and off the east coast Sunday while ridging builds over the Mississippi Valley. At the surface high pressure will be the dominant feature over the local forecast area. With high pressure at the surface and a lack of synoptic forcing aloft, a dry forecast has been maintained through the weekend. Mostly sunny skies, rain-free conditions, and temperatures within a few degrees of normal will make for a rather pleasant weekend across the forecast area.
Long Term - Monday Night Through Thursday
Broad troughing aloft will prevail just off the southeastern coast through the period, while ridging across the Mississippi Valley slowly weakens. A mid-level trough is forecast to slowly swing eastward from the Rockies, approaching the southeastern states near the end of the week. At the surface, high pressure will remain in control through mid week, slowly weakening as the upper level disturbance approaches later in the week. With the trough displaced so far offshore, little to no synoptic forcing will be present over the forecast area and therefore a dry forecast has been maintained. Temperatures are forecast to be within a degree or two of normal.
Today and tonight, surface high pressure will continue to ridge over the marine zones through the near term. Northeast winds of 15 to 20 kts will likely continue outside the CHS Harbor today, decreasing to 10 to 15 kts tonight. Seas should range between 3-6 ft today and tonight.
Saturday through Wednesday: High pressure will prevail over the land zones while a trough persists off the southeastern coast. This pinched pressure gradient will yield slightly enhanced northeasterly winds across the marine waters, generally 15 to 20 knots. A Small Craft Advisory remains in effect for the 20-60 offshore GA waters through Thursday morning for seas of 6-8 ft. Additional marine zones may need to be added to the Small Craft Advisory at a future juncture for 6 ft seas.
Several days of moderate northeasterly winds, a small amount of swell energy, and the recent Perigee and Full Moon will lead to an enhanced risk of rip currents into at least this weekend. A Moderate Risk of rip currents is in effect for all beaches today and Saturday. The risk could very well remain enhanced into early next week with similar wind and swell conditions.
Tides / Coastal Flooding
A Coastal Flood Advisory has been issued for all coastal zones from Charleston to McIntosh County for this morning's high tide. The latest expectations are for tides to reach 7.8 to 8.0 feet Mean Lower Low Water at Charleston, and 9.8 to 10.0 feet Mean Lower Low Water at Fort Pulaski. It is possible that a Coastal Flood Warning may become necessary for Charleston and coastal Colleton Counties this morning. High tide occurs around 8 to 9am Friday.
A continuation of at least moderate northeasterly winds, plus tides that are already elevated due to the Perigean Spring Tides, will result in a multi-day period of coastal flooding during each of the two daily high tides. At least moderate coastal flooding will occur in Charleston and coastal Colleton, with minor to moderate flooding from Beaufort to coastal McIntosh, including the Tybee/Savannah area. These conditions will continue into the weekend, maybe even into early next week. With such a prolonged period of elevated tides, areas of beach erosion will also occur.
NOAA Charleston SC Office: Watches - Warnings - Advisories
GA...Coastal Flood Advisory until 10am EDT this morning for GAZ117- 119-139-141. SC...Coastal Flood Advisory until 10am EDT this morning for SCZ048>051.
Small Craft Advisory until 8am EDT Thursday for AMZ374.