Area Forecast Discussion
Issued by NWS Charleston, SC
Issued by NWS Charleston, SC
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896 FXUS62 KCHS 301141 AFDCHS Area Forecast Discussion National Weather Service Charleston SC 641 AM EST Sun Nov 30 2025 .SYNOPSIS... High pressure will prevail into Monday, and then a storm system will pass through the region late Monday into late Tuesday. High pressure returns for the middle to end of next week. && .NEAR TERM /THROUGH TONIGHT/... This morning, KCLX detected isolated weak showers over the nearshore waters of GA/SC, drifting towards shore. These showers were developing within an inverted sfc trough over the Atlantic waters. These isolated showers should remain through much of the day, supported may PW values around 1 inch, weak values SBCAPE, and periods of LLVL moisture convergence. It is possible that these showers may brush the coast today, but measurable rainfall is not expected. Otherwise, the primary weather feature will be a cold front approaching from the west. Near term guidance indicates that the front will remain west of the forecast area through the daylight hours. Temperatures are expected to peak across the SC Lowcountry in the mid to upper 60s with low 70s across southeast GA. The cold front is timed to sweep across the CWA this evening. Isolated showers may develop along and ahead of the front, especially across the inland counties. The forecast will feature SCHC PoPs inland and along the coast, resulting in little to no QPF. Low temperatures should range from the mid 40s inland to the low 50s along the coast. && .SHORT TERM /MONDAY THROUGH WEDNESDAY/... On Monday, another cold air damming scenario unfolds as surface high pressure builds into the region from the north throughout the day, with the aforementioned cold front being pushed off to our south into northern Florida. This will drop afternoon temperatures back down into the mid 50s to mid 60s, warmest across southeast Georgia. Chances for rainfall remain low throughout the day (<20%), though mostly cloudy skies remain expected. As an upper-level trough move towards the area before lifting up into the northeast coast, a surface low will be moving towards the area from the Gulf which will be increasing rainfall chances Monday evening and overnight into Tuesday. Model consensus has shifted the track of the low back towards the coast, but the heaviest rainfall remains more across the midlands than the coast. Timing of the heaviest rainfall from showers and isolated thunderstorms for the region looks most likely during the morning hours on Tuesday as the surface low traverses the region, though lingering light rain will be possible into the evening hours. Despite precipitable water percentiles ranging from 90 to 97.5 of climatology, which are in the 1.5-1.75 inch range, rainfall amounts look to remain largely in the 0.5-1.0 inch range, highest across inland southeast South Carolina. Given the current drought conditions and lack of recent appreciable rainfall, no flooding concerns are expected. Chances for rainfall dwindle overnight into Wednesday, with surface high pressure building into the region behind the cold front. With strong zonal flow aloft, the surface high pressure begins to moves towards the coast by the evening hours on Wednesday. && .LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/... As the aforementioned surface high pressure moves offshore, temperatures will begin to nudge back to near normal, though likely remaining a few degrees shy in the mid 50s to lower 60s Thursday and Friday as another surface high pressure develops over the central CONUS. Model consensus remains rather poor for the end of the week as they struggle to determine what to do with the strong shortwave/trough along the west coast, with the NBM bringing back low-moderate (20-40%) chances for rainfall on Friday. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... VFR conditions will prevail at KCHS, KJZI, and KSAV through 12z Monday. Prior to the 12Z TAFs, KCLX detected isolated showers along the Charleston County coast, it is possible that brief periods of restrictions could occur at KJZI this morning. Otherwise, light winds are forecast through the period, generally 5 kts or less. A weak cold front should sweep across the terminals this evening, bringing thick mid- level clouds. Extended Aviation Outlook: There are moderate probabilities (30-50%) for flight restrictions Monday, due to low ceilings. A storm system will bring higher probabilities (50-80%, lowest along the coast) of flight restrictions late Monday into Tuesday, with both low ceilings and lowered vsbys possible in addition to rain showers and scattered thunderstorms. && .MARINE... Today, a weak pressure gradient will remain across the adjacent Atlantic waters as a cold front approaches from the west. Varying winds are expected to remain between 5 to 10 kts. Seas should range between 2 to 4 ft. The cold front is timed to sweep across the marine zones this evening. In the wake of the front, northeast winds should develop, speeds between 10 to 15 kts. No significant in wave heights tonight. Monday through Thursday: Behind a cold frontal passage, winds may approach small craft criteria on Monday along the southeast coast, with some 6 foot seas also possible as a coastal surface trough develops. Overnight into Tuesday, a surface low pressure begins to move towards the region, traversing the area on Tuesday. This will bring the highest rainfall chances Tuesday morning, with both showers and isolated thunderstorms possible, decreasing into the evening hours. Winds currently looking sub-advisory and will be varying directions throughout the day, but seas do build and begin to approach/exceed 6 feet again on Tuesday. Thus, small craft advisories may be needed, especially in the offshore Georgia waters where seas approach 8 feet 60nm out. High pressure returns on Wednesday, with conditions improving and no marine hazards expected into the end of the week. && .TIDES/COASTAL FLOODING... Chances for minor coastal flooding return with the Tuesday early morning high tide, along the Charleston and Colleton county coast. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...None. && $$ NEAR TERM...NED SHORT TERM...APT LONG TERM...APT AVIATION...APT/NED MARINE...APT/NED