405 FXUS62 KCHS 071954 AFDCHS Area Forecast Discussion National Weather Service Charleston SC 354 PM EDT Fri Oct 7 2022 .SYNOPSIS... A weak cold front will move through the region early Saturday. High pressure will then build across the region behind the front and remain dominant through much of next week. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... The mid-levels will consist of west-southwest flow overhead, with a trough moving across the Great Lakes region. At the surface, a cold front over the Appalachians this evening will approach our area overnight. The front may barely make it into our far inland counties by daybreak Saturday, but it probably won't make it to the coast. The front lacks moisture, so we're forecasting dry conditions. The question will be cloud cover. There should be some high clouds with the front late tonight. But if there are less clouds than expected, then this will lead to more radiational cooling and lower temperatures overnight. Given the current satellite imagery, we leaned towards the lower temperatures. Also, less clouds could make it easier for some patchy shallow fog to form across portions of our area late. Some of the models are already hinting at this, so we added this to the forecast. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/... Surface cold front stretches NE-SW across the Appalachians this afternoon and expected to move through the CWA overnight through early Saturday morning. No significant weather is anticipated with the front, but it will usher in slightly cooler air into the region for the weekend, knocking temps back to a little below normal, particularly on Sunday. There may be some lower cloud cover that spreads down through the region with the cooler air...Saturday night into Sunday...that might make low temperature forecasts a bit tricky. But otherwise, overall quiet conditions will be the rule through the short term period. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... Low amplitude short-wave ridging and large expanse of surface high pressure will be the dominant players across the region through a good portion of the period. Temperatures will run right around normal for mid October. By later in the week, a fairly vigorous/deep short-wave trough is forecast to deepen over the Great Lakes with suppressed heights down through the SE CONUS. This may drive a fairly strong cold front through the region late Thursday into Friday and bring our next chance for rainfall. && .AVIATION /20Z FRIDAY THROUGH WEDNESDAY/... 18Z TAFs: Mainly VFR. There could be some shallow ground fog early Saturday morning, but the probabilities of flight restrictions are currently too low to warrant mention in the TAFs. Extended Aviation Outlook: Some lower cloud cover might spread into the region Saturday night into Sunday. Otherwise, overall VFR conditions will prevail. && .MARINE... Through Sunset: A sea breeze will continue to produce onshore winds with occasional gusts near the land/sea interface. Tonight: A cold front will approach from the northwest, causing winds to initially be from the southeast in the evening. The front will almost make it to the waters late tonight, causing winds to veer to the southwest by daybreak Saturday, while remaining sustained at 10 kt or less. Seas will be in the 1-2 ft range. Extended Marine: A cold front will move through the region early Saturday with winds veering into the north/northeast by later in the day. Winds will also increase Saturday and remain a bit gusty through the early part of next week. Conditions are expected to remain below Small Craft Advisory criteria through Monday. But seas could build to 6 ft across the GA waters beyond 20 nm Tuesday through midweek. && .TIDES/COASTAL FLOODING... For the evening high tide (~7 pm)... At Charleston, the astronomical high tide is 6.55 ft MLLW. Positive tidal departures persist despite the somewhat unfavorable coastal winds. The tide should barely hit minor flooding, so a Coastal Flood Advisory is in effect for Charleston and coastal Colleton Counties. At Fort Pulaski, the astronomical high tide is 8.39 ft MLLW. Based on the latest tidal departures, the tide will probably not be high enough to generate coastal flooding. Astronomical influences from the upcoming full moon will lead to elevated tide cycles this weekend and into next week. 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...Coastal Flood Advisory until 8 PM EDT this evening for SCZ049- 050. MARINE...None. && $$ NEAR TERM... SHORT TERM...TBA LONG TERM...TBA AVIATION...TBA MARINE...TBA TIDES/COASTAL FLOODING...