Edisto Beach, SC to Savannah, GA Marine Forecast
|This Afternoon...S Winds 10 To 15 Kt. Seas 3 To 4 Ft. A Chance Of Showers And Tstms.|
|Tonight...Sw Winds 10 To 15 Kt. Seas 3 To 4 Ft, Subsiding To 2 To 3 Ft After Midnight. A Slight Chance Of Showers And Tstms.|
|Sun...Sw Winds 5 To 10 Kt, Becoming S 10 To 15 Kt In The Afternoon. Seas 2 To 3 Ft. A Slight Chance Of Showers And Tstms In The Afternoon.|
|Sun Night...Sw Winds 10 To 15 Kt. Seas 2 To 3 Ft. A Slight Chance Of Tstms. A Chance Of Showers, Mainly In The Evening.|
|Mon...Sw Winds 5 To 10 Kt, Becoming S In The Afternoon. Seas 2 To 3 Ft. A Slight Chance Of Showers And Tstms In The Morning, Then A Chance Of Showers And Tstms In The Afternoon.|
|Mon Night...S Winds 10 Kt, Becoming N After Midnight. Seas 2 To 3 Ft. A Chance Of Showers And Tstms.|
|Tue...Se Winds 5 To 10 Kt. Seas 2 Ft. A Chance Of Showers And Tstms.|
|Tue Night...Se Winds 5 To 10 Kt. Seas 2 Ft. A Chance Of Showers And Tstms.|
|Wed...Se Winds 5 To 10 Kt. Seas 2 Ft. A Slight Chance Of Showers And Tstms.|
|Wed Night...S Winds 10 To 15 Kt. Seas 3 To 4 Ft. Winds And Seas Higher In And Near Tstms.|
| Area Forecast Discussion|
National Weather Service Charleston SC
152pm EDT Sat May 21 2022
Several upper disturbances and a few fronts should lead to unsettled weather at times into late next week.
Near Term - Through Tonight
This Afternoon: High pressure will prevail across the western Atlantic, but the mid-upper level ridge axis should nudge further offshore while pockets of mid-level energy traverse along its western periphery across the Southeast United States. Early this afternoon, convective initiation has taken place across the Midlands, just west of the local area primarily where greatest surface heating is occurring. Further south and closer the coast, cirrus clouds associated with convection over the northern Gulf of Mexico continue to spread across the region, limiting surface heating. The setup should only delay convective development across southern areas for a few hours until peak diurnal heating when south-southwest surface winds advect deeper moisture in the region (PWATs (Precipitable Waters) around 1.75 inches). Showers and thunderstorms should develop and increase in coverage by mid- afternoon, a few of which could be strong and/or marginally severe along/ahead an inland moving seabreeze late afternoon into early evening. Latest mesoanalysis suggests weak shear across the region, but MLCAPE values ranging between 2500-3000 J/kg, DCAPE around 800 J/kg, and PWATs (Precipitable Waters) near 1.75 inches suggest the potential of pulse type convection capable of producing isolated instances of damaging winds and/or hail, especially if thunderstorms interact with outflow boundaries and/or a sea breeze circulation. Areas of brief heavy rainfall are also possible due to slower moving thunderstorms and greater precipitation coverage than previous days. The Storm Prediction Center currently marks the entire area in a Marginal Risk of severe weather for today. Shower and thunderstorm activity could linger into early evening hours along remnant boundaries. Diurnal heat loss will eventually take over, resulting in convection weakening/diminishing.
Outside thunderstorms, winds could be fairly breezy along the coast where a sea breeze circulation develops this afternoon (~20 mph). High temps should generally range in the mid-upper 80s, while some areas approach 90 degrees across inland Georgia.
Tonight: Early evening convection coverage and placement will be driven mostly by boundary interactions and location of the sea breeze. We should maintain at least isolated coverage through about midnight, with mostly dry conditions expected for the latter half of the night. Lows are forecast to range from the upper 60s inland to the low 70s along the coast.
Short Term - Sunday Through Tuesday
Atlantic high pressure and an inland trough should prevail at the surface until a cold front moves into the area Monday. The front should push into at least inland portions of the Lowcountry before basically stalling out into Tuesday. Increased moisture levels, upper level shortwaves and the aforementioned stalling cold front will be the main triggers for higher than normal rain chances each day, especially inland during the afternoons/evenings. Fortunately, the lack of strong deep layer shear will preclude much organized convection and the overall severe storm risk. However, the slow storm motions could enhance the risk of localized flash flooding. Temperatures should mainly stay near to above normal, although could end up below normal Tuesday when at least a portion of the area will be on the north side of the front.
Long Term - Tuesday Night Through Saturday
A stalled front over or near the area to start the period will eventually lift north as a warm front by Wednesday night ahead of an approaching cold front. There seems to be a bit more model agreement now that the late week cold front could move into and possibly even through the Lowcountry/Coastal Empire Friday night into Saturday which could lead to drier conditions than currently forecast. Should see higher than normal rain chances much of the period with temperatures generally near to above normal.
This Afternoon through Tonight: South/southwest winds will prevail across local waters through tonight. Wind speeds are expected to peak this afternoon into the evening, primarily along the land/sea interface where a sea breeze circulation occurs. Wind speeds up to 15-20 kt will be common during this period, and a few isolated gusts to 25 kt winds can't be ruled out, mainly near the Charleston Harbor. However, conditions should fall short of Small Craft Advisories. Seas are expected to remain in the 2-4 ft range.
Sunday through Thursday: Atlantic high pressure will prevail across the southern SC/northern GA Atlantic nearshore waters into early next week before a cold front likely pushes into the area Monday night and lingers into Wednesday. This will lead to some varying wind directions depending on the position of the front and this is probably the least confident portion of the forecast. Although there will likely be some enhanced winds at times, especially Thursday, conditions overall should stay below Small Craft Advisory levels as significant wave heigheights should stay mostly below 5 feet.
May 21 Record High Min Temperatures: KCHS: 74/last set in 2001 KCXM: 78/1998 KSAV: 74/last set in 2017
NOAA Charleston SC Office: Watches - Warnings - Advisories