244 FXUS62 KCHS 120849 AFDCHS Area Forecast Discussion National Weather Service Charleston SC 449 AM EDT Tue Mar 12 2019 .SYNOPSIS... High pressure will build north of the region through mid week then linger into late week. Another cold front will sweep across the region Friday night. High pressure should then return by early next week. && .NEAR TERM /THROUGH TONIGHT/... Pre-dawn: Clouds have been decreasing since midnight with mainly just high clouds remaining over the area. There has been some isolated stratus and fog forming over inland GA and we opted to mention patchy fog nearing sunrise over a few zones well inland from I-95. Otherwise, temps were falling as low-level cold advection ongoing across the region. We adjusted temps a bit lower than the evening forecast to initialize. Today: Surface high pressure will build over the Mid Atlantic Region while ridging aloft builds north from the Lower Gulf Coast Region. Much drier deep layered air in store for the area today with only occasional high clouds spilling over the ridge axis from time to time. We made very few and minor changes to forecast temperature schemes and max temps today. Highs near 68 degrees far north to 73 degrees far south the average 5 degree range with beaches and barrier islands running cooler thanks to northeast breezes and gusts topping 20-25 mph at times through mid afternoon. Tonight: High pressure will settle north of the area while mainly clear skies dominate our region. Coolest temps are expected over northern and inland zones where a few spots dip close to 40 degrees. Mid to upper 40s will be common over inland Southeast GA but the northeast flow will keep milder readings in the 50s right on the beaches and barrier islands. && .SHORT TERM /WEDNESDAY THROUGH FRIDAY/... Wednesday and Thursday: Dry conditions will prevail through mid-week as sfc high pressure centered over Mid-Atlantic and Northeast states gradually shifts further east over the western Atlantic. Sfc winds will turn from east to south-southeast across the area in response to the high shifting further offshore mid-week while a mid/upper lvl ridge of high pressure extends across the region before its axis eventually shifts off the Southeast Coast by Thursday. Given the setup, a warm-up is expected mid to late week. In general, highs should approach the low/mid 70s Wednesday afternoon, followed by noticeably warmer conditions in the upper 70s to around 80 Thursday afternoon before the onset of clouds. Friday: A large mid/upper trough of low pressure will shift over the East Conus with a south/southwest extending cold front that eventually reaches the Southeast United States Friday evening and night. Ahead of the front, south/southwest sfc winds will help drive warm/moist air to the region, which should bring some showers and thunderstorms to inland areas mid afternoon through the evening. In general, temps should warm into the upper 70s to around 80 before the onset of precip. At this time, the threat of severe weather remains low. && .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... A cold front is anticipated to shift through the region Friday night into early Saturday, bringing chances of precip across most areas as PWATs approach 1.50-1.70 inches along/near fropa. The front should then push well offshore by daybreak Saturday with cool/dry high pressure returning to the area late weekend into early next week. Once fropa occurs, temps will struggle to warm into the mid/upper 60s Saturday, Sunday and Monday afternoon. Overnight lows should also be cooler, dipping into the low/mid 40s inland to upper 40s/lower 50s near the coast Saturday night and Sunday night. The next chance of precip to the region could arrive along/near the coast as a low develops offshore. && .AVIATION /08Z TUESDAY THROUGH SATURDAY/... VFR expected at KCHS/KSAV through 06Z Wednesday. Extended Aviation Outlook: VFR conditions are expected at both CHS and SAV terminals through early Friday. Flight restrictions are possible at both terminals Friday evening/night into early Saturday due to showers and/or thunderstorms along a passing cold front. && .MARINE... High pressure will build north of the waters through tonight with cooler northeast flow expected over all of our waters. Cold (and drier) air advection over the waters today will result in steeper low level lapse rates and improved mixing profiles. It was a close call on opting out on a Small Craft Advisory both Charleston Waters and GA waters beyond 20 NM. Surging will strengthen this morning with close to 20 kt winds developing for a period before speeds tend to subside over SC waters after mid afternoon. Seas were only 2 ft to initialize out at buoys 41004 and 41008 and wave guidance hinted at some 6 ft seas right at the outer fringe of the GA waters later today. We will be monitoring for updates as the main concern areas closer to the Gulf Stream east of the GA coast. Tonight: High pressure settles north of the waters and both thermal and pressure gradient remain decent and supportive of onshore flow 15-20 kt outer GA waters and up to 15 kt at times near shore legs. Seas will range from 3-4 ft withing 20 NM and 4-5 ft offshore. Wednesday through Sunday: Conditions should slowly improve over all waters mid week as high pressure centered north/northwest of the area shifts off the Mid-Atlantic Coast and turns sfc winds more east Wednesday, then south Thursday and Friday. In general winds should peak around 15 kt mid week while seas range between 2-4 ft, highest in offshore Georgia waters. There should be a slight uptick in winds Friday afternoon into Saturday as a cold front approaches, then shifts over coastal waters Friday night. South/southwest winds peaking around 20 kts will likely shift to north/northwest post fropa. Seas should range between 2-4 ft. High pressure will then prevail late Saturday through Sunday. Conditions should remain below Small Craft Advisory levels during the weekend. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...None. && $$ NEAR TERM... SHORT TERM...DPB LONG TERM...DPB AVIATION...DPB MARINE...DPB