Marine Weather and Tide Forecast for Darien, GA

NEAR TERM /THROUGH TONIGHT/
Through This Evening: Convection is starting to get going across parts of the Lowcountry into Southeast Georgia. This activity is forming within a ribbon of higher 850-700 hPa moisture juxtaposed with a corridor of moderate to locally strong mixed- layer instability. Activity is expected to slowly develop over the next few hours, peaking in coverage by late afternoon, then diminishing this evening with the onset of nocturnal cooling.
There are still some signals that convection could locally concentrate in the area from roughly Moncks Corner and Shulerville southwest to North Charleston, Summerville, Harleyville into Walterboro as the resultant sea breeze moves inland and intersects the lake breeze around Lake Moultrie and what looks to be a southwest- northeast oriented outflow/mesoscale boundary stretching from Walterboro to Harleyville. Pops 20-30% were maintained through late afternoon with pops dropping below mentionable thresholds over the interior during the early evening hours. Shear will remain quite weak, but a pulse strong to marginally severe tstm could occur with gusty winds and cloud- to-ground lightning being the primary hazards given DCAPEs will be near 1000 J/kg by peak heating.

Tonight: Dry and warm conditions will continue. As skies clear and the boundary layer decouples, some shallow ground fog could develop, especially over the interior portions of the Lowcountry where the greatest of the rainfall and lower 1000 hPa condensation pressure deficits are expected to occur. Dense fog is not expected at this time. Lows will range from the lower 70s well inland to around 80 at the beaches and Downtown Charleston.

SHORT TERM /SUNDAY THROUGH TUESDAY/
A strong upper-lvl ridge will build over the Southeastern CONUS throughout early next week. Latest model guidance continues to indicate subsidence filtering into the mid-lvls throughout this period. This will limit PoPS to less than 20% in the afternoon, however if any convection develops, it will be along the seabreeze and it will be extremely limited in coverage.
Temperatures will climb into the low to mid 90s on Sunday and Monday, with heat indices just below and/or near 100. On Tuesday highs will reach into the mid to upper 90s with heat indices creeping into the low 100s. As of right now, heat indices remain just below Heat Advisory criteria, but this will continue to be monitored over the next couple days. This sort of heat is not uncommon for this time year, however it is important to remember to stay hydrated and limit outdoor activity (esp. in the afternoon). Overnight lows will remain mild with temperatures only dipping into the low to mid 70s.

LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/
This aforementioned strong upper-lvl ridge will continue to stay situated over the region and limit shower and thunderstorm activity in the afternoons. Recent guidance has maintained rain chances below 20% PoPS through much of the next week, trending back towards seasonable scattered coverage as the upper ridge beings to break down Friday into the weekend. Temperatures remain above normal in the mid to upper 90s inland, with the chance for a few locations to hit 100 each afternoon, while highs are a bit more moderate where the sea breeze reaches in the afternoon, likely lower 90s along the coast. Dew point values will be the determining factor in whether or not we hit heat advisory criteria (108) each afternoon, but the current expectation is that inland areas will mix into the upper 60s, with coastal areas lower to mid 70s, resulting in heat index values reaching around 105, but potentially briefly surging to near 110 immediately along the sea breeze front. Again, overnight lows look to remain mild.

AVIATION /18Z SATURDAY THROUGH THURSDAY/
21/18z TAF Discussion: KCHS/KJZI/KSAV: VFR for much of the period. Scattered tstm are expected to develop near KJZI and KCHS through mid-afternoon.
Activity looks to get closer to KCHS than KJZI, so VCTS was highlighted at KCHS through 21z. A last minute adjustments strong upper-lvl ridge will build over the Southeastern CONUS throughout early next week. Latest model guidance continues to indicate subsidence filtering into the mid-lvls throughout this period. This will limit PoPS to less than 20% in the afternoon, however if any convection develops, it will be along the seabreeze and it will be extremely limited in coverage.
Temperatures will climb into the low to mid 90s on Sunday and Monday, with heat indices just below and/or near 100. On Tuesday highs will reach into the mid to upper 90s with heat indices creeping into the low 100s. As of right now, heat indices remain just below Heat Advisory criteria, but this will continue to be monitored over the next couple days. This sort of heat is not uncommon for this time year, however it is important to remember to stay hydrated and limit outdoor activity (esp. in the afternoon). Overnight lows will remain mild with temperatures only dipping into the low to mid 70s. may be needed pending radar trends at issuance time. For KSAV, activity looks to remain west and too isolated for any TSRA mention at this time.
Some shallow ground fog could develop early Sunday morning, mainly at KCHS and JZI where lower 1000 hPa condensation pressure deficits are progged. Conditions were limited to 6SM MIFG from 09-13z for now.

Extended Aviation Outlook: Strong upper ridging will limit the convective potential, and VFR conditions are expected to prevail.

MARINE
Tonight: Quiet conditions will prevail with south winds 5-10 kt and seas 1-2 ft.

Sunday through Wednesday: High pressure overhead keeps a weak gradient in place through midweek, with breezy conditions limited to the sea breeze near shore each afternoon. S to SW winds become moderate late week as the high center shifts toward a more seasonable Bermuda High position. Weak medium period trade swell keeps seas 1-3 ft through the period.

Rip Currents: A 2 ft, 8 sec swell will impact the beaches through this evening. A moderate rip risk continues through 8 PM for the Georgia beaches since it is a weekend and the Tybee Island beaches are especially vulnerable to rip currents in this type of swell regime.

CHS WATCHES/WARNINGS/ADVISORIES
GA...None.
SC...None.
MARINE...None.