299 FXUS62 KCHS 301710 AFDCHS Area Forecast Discussion National Weather Service Charleston SC 1210 PM EST Tue Dec 30 2025 .SYNOPSIS... High pressure will prevail for the remainder of the week, followed by a cold front moving through the area this weekend. && .NEAR TERM /THROUGH TONIGHT/... The base of a H5 longwave trough will remain over the region tonight. Downslope H85 flow should support a sfc lee trough across the Carolinas tonight. Northwest flow should also yield weak CAA through this evening, with some slow recovery late tonight. Near term guidance indicates that sub-zero H85 temperatures will remain over the CHS Tri-county through daybreak Wednesday. The sfc pressure gradient will remain very weak this evening, increasing to around 2 mb by the pre-dawn hours. After light to calm winds this evening, wind speeds over portions of SE GA may increase to around 5 mph late tonight, providing some mixing. It is interesting to note that the HREF indicates a solid band of mountain wave cirrus over the western Carolinas this evening, it is possible that some tufts of cirrus could reach the Midlands before dissipating. Given the clear sky and light winds, low temperatures are forecast to range in the mid to upper 20s along and west of I-95, with values around 30 degrees east. The cold temperatures combined with wind up to 5 mph may yield some low 20s wind chill across inland GA. Similar to this morning, conditions appear just above criteria for a Cold Weather Advisory. && .SHORT TERM /WEDNESDAY THROUGH FRIDAY/... While not quite as cool, Wednesday will remain on the cooler side of normal as northwesterly flow persist. Ample sunshine should help make it feel a little warmer, with afternoon highs expected to be in the lower to mid 50s. Overnight, lows dip down into the mid 30s across inland areas while areas near the beaches are a bit warmer in the upper 30s to lower 40s. A weak front moves through on Thursday, bringing a resurgence of westerly winds across the area which become marginally gusty in the teens, along with high temperatures in the upper 50s to lower 60s. Overnight into Friday, radiational cooling brings overnight temperatures back into the mid 30s inland and up to the lower/mid 40s along the coast. Temperatures continue to moderate on Friday as a warm front lifts across the region, bringing afternoon temperatures in the lower to mid 60s. && .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... Behind the warm front, overnight lows into the weekend will be much warmer in the mid 40s to lower 50s. A weak shortwave looks to move across the area on Saturday, accompanied by a surface low pressure system in some models. This will bring chances for light to moderate rain showers starting early Saturday morning and ending overnight into Sunday, along with temperatures in the lower to upper 60s. Ensemble clustering analysis shows that model agreement is fairly high, with the two dominant clusters showing 70-80% probabilities for a quarter inch of rain across across southeast South Carolina, and 50-70% probabilities across southeast Georgia. Probabilities for half an inch of rain are about 20-30% less across the board. Temperatures cool into the mid 50s to lower 60s on Sunday as a cold front moves through, warming up into the lower to mid 60s on Monday. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... 18Z TAFs: VFR. West-northwest winds should remain between 5 to 10 kts through the rest of this afternoon, then becoming light and variable early this evening. Northwest winds between 5 to 10 kts should redevelop during the early daylight hours Wednesday morning. Extended Aviation Outlook: VFR conditions expected to prevail through the rest of the week. Chances for rain return on Saturday, along with possible flight category restrictions from both lowered cigs and vsbys. && .MARINE... Tonight, the pressure pattern will support northwest winds between 10 to 15 kts, strongest over the GA waters. Wave heights will range between 2-4 ft. Wednesday through Saturday: Winds remain out of the northwest throughout most of Wednesday as surface high pressure builds across the southeast. Winds pickup overnight into Thursday as a front moves towards and then through the area, bringing the waters from Savannah to Altamaha Sound 20-60nm out to Small Craft Criteria, due to wind gusts near 25 knots for a few hours Thursday morning. Westerly winds remain gusty throughout the day, weakening overnight into Friday. Chances for rain return on Saturday as a cold front begins to move through, with gusty winds near Small Craft Criteria possible, especially in the outer Georgia waters Saturday morning/afternoon. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...None. && $$ NEAR TERM...NED SHORT TERM... LONG TERM... AVIATION...NED MARINE...