659 FXUS62 KCHS 271753 AFDCHS Area Forecast Discussion National Weather Service Charleston SC 153 PM EDT Sat Apr 27 2024 .SYNOPSIS... High pressure will prevail through much of next week. A weak cold front could approach late next week. && .NEAR TERM /THROUGH TONIGHT/... This Afternoon: Aloft, the axis of a mid-upper lvl ridge will extend across the Southeast United States. At the sfc, the local area will remain along the southern periphery of high pressure centered to the north while subtle coastal troughing persists off the Southeast Coast. Weak isentropic ascent along with sufficient low-lvl moisture driven onshore has allowed a few showers to develop across southeast South Carolina early this afternoon, which could also drift into parts of southeast Georgia by mid afternoon. Expect activity to remain isolated, light and diurnally driven, peaking in coverage during the next few hours, then waning late afternoon. Regardless of precip, an east-southeast low-lvl flow should continue to produce scattered to broken cumulus/stratocumulus through the day. This could play a role in limiting sfc heating potential for the rest of the afternoon. Latest guidance still suggests afternoon highs in the upper 70s to lower 80s, warmest across southeast Georgia. The pressure gradient has weakened considerably across the area early this afternoon, mainly due to high pressure nudging further south and holding more firm across southeast South Carolina and southeast Georgia. For this reason, east/southeast winds are expected to remain a bit lighter than previously forecasted, generally peaking between 10-15 mph with an occasional gusts to 20-25 mph during a seabreeze. Tonight: There is very little change in the pattern both surface and aloft, with still some hints of a subtle trough over the ocean. While there can be few-scattered cumulus/stratocumulus from off the Atlantic, most cloud cover will be of the mid and high level variety. Winds will decouple in some far inland locations. But there is still enough of a gradient around the high to keep things mixed just enough across a good chunk of the region. As a result, minimum temperatures will rang from the mid 50s to lower 60s inland, middle 60s near and along the coast. && .SHORT TERM /SUNDAY THROUGH TUESDAY/... An upper trough will remain centered over the area on Sunday while surface high pressure sits just off the coast, maintaining a moderate southeast flow. A decent layer of cumulus should develop during the daytime hours given the moist onshore flow in the lower levels. Highs will be near normal in the upper 70s to lower 80s. The upper ridge axis will shift east on Monday while the surface high strengthens over the western Atlantic. The low-level flow will become more southerly on Monday, while thickness advection results in a warming trend with highs in the low to mid 80s. A weak shortwave will pass by to the north Tuesday afternoon. Limited forcing and moisture point to dry weather on Tuesday, though we can't rule out an isolated shower or tstm in the afternoon, especially inland. Highs will be in the mid 80s in southern SC and upper 80s in southeast GA. && .LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/... A quasi-zonal flow will persist aloft while Bermuda high pressure sits to our east. A cold front could drop into the area Friday night or Saturday, though rain chances do not look particularly high. Above normal temperatures expected with highs climbing into the upper 80s to lower 90s. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... VFR conditions are expected to prevail at KCHS, KJZI, and KSAV through 18Z Sunday. East-southeast winds will average 10-15 kt this afternoon with peak wind gusts near 20 kt. There are some hints of MVFR cigs reaching the SAV terminal late tonight/near daybreak Sunday morning, but confidence remains too low to include in the latest 18Z TAF issuance. Extended Aviation Outlook: Prevailing VFR conditions. && .MARINE... This Afternoon: Sfc high pressure centered well to the north has made a slight push south, more so that the pressure gradient has weakened a bit across local waters. For this reason, east-southeast winds should remain lighter, peaking between 10-15 kt closer to the coast where the seabreeze starts an inland shift. A Small Craft Advisory will remain in effect across offshore Georgia waters, mainly for seas up to 6 ft. Tonight: The local pressure gradient slackens a tad as the surface high sags a little south, with the center off the Delmarva. Winds and seas won't change much from the daytime, with a continuation of the Small Craft Advisory on the Georgia waters beyond 20 nm offshore, for seas up to 6 or 7 feet. Winds on Sunday will turn more to the southeast, allowing seas to slowly subside. The 6 footers in the offshore GA waters should dissipate by late Sunday afternoon. Quiet marine conditions expected through next week as Atlantic high pressure prevails. Wind directions will gradually turn from SE to S by the middle of next week. Speeds should generally be no higher than 15 kt, though we expect a fairly strong afternoon sea breeze along the coast each day, potentially gusting to 20 kt at times in Charleston Harbor. Rip Currents: Moderate onshore winds will continue through the weekend, while approximately 2 or 3 ft waves every 7-8 seconds reach the beaches. The local rip current calculator indicates a Moderate Risk of rip currents along all beaches today, then lingering along the Georgia beaches Sunday. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...Small Craft Advisory until 6 PM EDT Sunday for AMZ374. && $$ NEAR TERM...DPB SHORT TERM...JRL LONG TERM...JRL AVIATION...DPB MARINE...DPB