433 FXUS62 KCHS 070235 AFDCHS Area Forecast Discussion National Weather Service Charleston SC 1035 PM EDT Thu Oct 6 2022 .SYNOPSIS... High pressure will prevail until a cold front moves through the area early Saturday. High pressure will then return for the weekend and early next week. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... Earlier this evening, KCLX detected a thin line of light dBZ associated with a sea breeze, drifting inland. Dewpoints in the wake of the sea breeze have risen well into the 50s, with low 60s along the coast. Temperatures across the coastal counties are forecast to cool into the mid to upper 50s, possibly exceeding the crossover temperatures over portions of the coastal counties. In fact, the 21Z run of the SREF increased the probabilities of 1 and 3 mile visibilities to 35 to 45 percent. Given the recent dewpoint observations, the updated forecast will feature a mention of patchy fog from the Santee River south to the Altamaha River. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/... Broad mid-level troughing will prevail to our north, with mainly zonal flow over our area through Sunday. At the surface, Atlantic High pressure will prevail through most of Friday. Thickness values support high temperatures a few degrees above normal, especially across our GA counties. A dry cold front is forecasted to move through the area early Saturday, bringing some clouds, but no rain. Cool air advection doesn't appear to be too strong behind the front, even when factoring in the northwest surface winds and building High pressure. In fact, High temperatures may only be a few degrees cooler on Saturday, which is still close to normal. Though, mostly clear skies and light winds Saturday night will lead to decent radiational cooling. Lows Saturday night will be a few degrees below normal, and they may still need to be dropped more with future forecasts. High pressure continues to build in from the northwest on Sunday. Though, the temperature gradient will be more pronounced with highs in the low to mid 70s across our northernmost tier and the mid 80s across our far southern/inland GA counties. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... High pressure will dominate our forecast as it slowly passes to our north through Thursday. The High will bring dry conditions through Wednesday night, with signs of increasing moisture later Thursday. Temperatures will be within a few degrees of normal. && .AVIATION /03Z FRIDAY THROUGH TUESDAY/... Prior to the 0Z TAFs, KCLX detected a thin line of light dBZ associated with a sea breeze, drifting inland. Dewpoints in the wake of the sea breeze have risen well into the 50s, with low 60s along the coast. Temperatures at KSAV and KCHS are forecast to cool into the mid to upper 50s, possibly exceeding the crossover temperatures at the terminals. The 0Z TAFs will feature a mention of IFR fog at KSAV, improving to VFR by 13Z. KCHS may see a period of ground fog between 9-14z. The fog should dissipate during the first hour or two of daylight, leaving light SSW winds and mostly clear sky through the rest of TAF period. Extended Aviation Outlook: VFR. && .MARINE... Tonight: No marine concerns tonight. Weak pressure pattern will keep south/southwest winds around 10 knots or less. Seas will average 1-2 feet. Extended Marine: High pressure will prevail on Friday, yielding sustained winds generally 10 kt or less. A cold front is forecasted to move through the area early Saturday, causing winds to veer to the northwest by late in the day. The surface pressure gradient will become somewhat enhanced Saturday night through the first part of next week, as High pressure builds in from the northwest, then passes to our north. Conditions are expected to remain below Small Craft Advisory criteria through Monday. Seas could build to 6 ft across the GA waters beyond 20 nm on Tuesday. && .TIDES/COASTAL FLOODING... Astronomical influences from the upcoming full moon will lead to elevated tide cycles this week. Moderate coastal flooding will be possible with the evening high tides through late week, mainly along the Charleston and Colleton County coasts. Over the weekend, both morning and evening high tides could have moderate to major coastal flooding along the Charleston and Colleton County coasts, then with the morning high tides through mid-week. From Beaufort County to McIntosh County, minor to moderate coastal flooding will be possible with the morning and evening high tides this weekend, then with the morning high tides through mid-week. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...None. && $$ NEAR TERM...NED SHORT TERM... LONG TERM... AVIATION...NED MARINE... TIDES/COASTAL FLOODING...