575 FXUS62 KCHS 230502 AFDCHS Area Forecast Discussion National Weather Service Charleston SC 1202 AM EST Thu Nov 23 2023 .SYNOPSIS... High pressure will briefly build across the area tonight through Thanksgiving Day. A weak area of low pressure will then impact the region Friday into Saturday. A cold front will push offshore early next week with high pressure returning thereafter. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... No major changes were made with the midnight update. Winds will continue to slowly diminish through the night as post-frontal cold air advection wanes. Lows from the upper 30s/near 40 in the Millen-Allendale corridor to the lower 50s at the beaches look on track. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/... Thursday: High pressure building into the region on Thanksgiving Day will make for quiet, rain-free weather conditions. Aloft, a shortwave across southern Texas will lift toward the Mississippi region. Deep moisture will spread out ahead of the disturbance which will lead to increasing cloud coverage in the evening. Increasing clouds will yield high temperatures in the low 60s, although it could get a bit warmer if the incoming moisture lags behind a bit. Overnight lows will drop into the mid 40s inland and low 50s along the immediate coast. Friday: A weakening shortwave trough will ripple across the southeastern states while surface cyclogenesis tries to initiate an area of low pressure at the surface. Models hint at initial development occurring over the SC Midlands before becoming a bit more established offshore the SC/GA coast. Isolated showers are possible early Friday, moving in from the southwest. Then as the deeper moisture migrates offshore in the afternoon, showers over land should follow suite. POPs over land remain in the slight chance range, with chance POPs occurring along the coast in the afternoon. High temperatures will again be in the low 60s. Cooler min temps are expected with lows in the 40s everywhere except for the beaches where it will drop to around 50 degrees. Saturday: Surface high pressure will wedge inland as the weak low offshore meanders near the Carolina coastline. Saturday will be rain-free over land, with showers limited to the Atlantic. Temperatures will reach the upper 50s to low 60s across southeastern SC and closer to the mid 60s across southeastern GA as the CAD setup forms east of the Appalachians. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... With the CAD setup in place Saturday night, temperatures could dip into the upper 30s inland, with mid/upper 40s closer to the coast. Cloud cover and winds around 5 to 10 mph through the overnight period will yield a low risk for frost development across the cooler inland zones. A weak cold front could approach the region Sunday night into Monday bringing showers, but conditions should quickly clear out for a rain-free period early next week once high pressure returns. Temperatures are forecast to decrease to slightly below normal for the long-term period. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... 23/06z TAF discussion: KCHS/KJZI/KSAV: VFR through the period. Extended Aviation Outlook: There is a slight chance of rain showers on Friday, possibly bringing some flight restrictions. Otherwise, prevailing VFR. && .MARINE... Overnight: Both winds and seas will continue to wane across the waters overnight. Seas at 41004 were down to 6.2 ft and 4.7 ft at the Charleston Pilot Buoy, so the Small Craft Advisory will be cancelled about an hour early. Thursday through Monday: High pressure will build into the region on Thanksgiving Day, with a weak area of low pressure forming over the SC/GA coast late Friday and meandering through Saturday. Northerly winds around 10 knots or less Thursday and Friday will shift to the NE on Saturday as surface high pressure builds inland. Winds will increase Saturday, with gusts 20-25 kt as the pressure gradient tightens with a weak low sitting nearly stationary offshore. Seas around 2-3 ft will increase in response, to around 3-6 ft late Saturday. Small Craft Advisories could be required mainly for the Charleston County nearshore waters and the outer GA waters (from 20- 60 nm) for both winds and seas. Conditions will improve Sunday as the low pressure system begins its northward progression away from the local waters. && .TIDES/COASTAL FLOODING... A recent lunar perigee and full moon on Monday will result in astronomical tide levels to increase to around 6.5 ft MLLW in the CHS Harbor. Periods of onshore winds may produce enough tidal departures to create minor coastal flooding during the morning high tide cycle. Any coastal flooding should occur between 530 and 930 AM. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...None. && $$