761 FXUS62 KCHS 302017 AFDCHS Area Forecast Discussion National Weather Service Charleston SC 317 PM EST Wed Jan 30 2019 .SYNOPSIS... Cold high pressure will dominate into early Friday. Weak upper level disturbances will affect the area over the weekend into early next week. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... A reinforcing shot of cold air is expected overnight as arctic high pressure builds from the northwest. Expect quite a bit of high clouds the first part of the night before clearer skies return for most areas, possibly lingering a good part of the night near the Altamaha River. Winds will generally be light enough to allow temperatures drop to freezing or colder for most areas except near the immediate coast. Inland areas should dip into the mid-upper 20s which means several hours of freezing temperatures and wind chills possibly into the lower 20s. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/... Cool, dry surface high pressure will remain north of the area Thursday through Saturday. As the high weakens and gradually shifts to the east, the return of warm air advection will result in a quick warming trend, with highs in the middle 60s by Saturday. Aloft, a series of weak disturbances will move across the northern Gulf Coast, resulting in a weak coastal trough developing off the GA coast. By Friday night or Saturday we could see isolated showers developing over the marine area and moving into coastal areas. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... This period continues to have a lot of model uncertainty. Latest model trends seem to be pointing toward possibly slightly higher PoPs through period. Again, the GFS is the driest, while the ECMWF and Canadian are more moist, but do have timing differences for Saturday night/early Sunday. Have continued slight chance PoPs most areas, but if just went with GFS solution, it would be much drier. By Sunday and into mid week, models continue to show generally zonal to slightly southwest upper flow with the main storm track remaining north and west of the area. Given model differences with moisture and timing of moisture, do not want to get caught up into trying to fine tune details at this point. Have continued mainly slight chance to low end chance PoPs through this period. All global models hinting that the best chance for precipitation might be at the very end of the period as the potential for another front to approach the area increases. Temperatures are still expected to continue to moderate through the period, remaining above normal. && .AVIATION /20Z WEDNESDAY THROUGH MONDAY/... VFR through 18Z Thursday. Extended Aviation Outlook: MVFR ceilings possible Saturday night and Sunday night as several upper disturbances move through. && .MARINE... Tonight: Arctic high pressure will build from the northwest with a reinforcing shot of cold air. Winds will begin the night from the west before shifting to the north late. Speeds will mainly be 20 kt or less with seas 2-3 ft near shore and up to 4 ft in the offshore waters. Thursday through Monday: High pressure will dominate Thursday through Friday night, remaining north or northeast of the waters with winds/seas below advisory levels. Models begin to show some significant differences Saturday, Saturday night and part of Sunday with the potential for a weak surface low center to develop over or just south of the waters. If this low center does develop, winds and seas could be a bit higher than currently forecast, especially over the southern half of the waters. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...None. && $$ NEAR TERM...RJB SHORT TERM...JRL LONG TERM... AVIATION...JRL/RJB MARINE...JRL/RJB