Marine Weather and Tide Forecast for Red Hill, SC

NEAR TERM /THROUGH TONIGHT/
Shortwave ridge at 5h slips east today, helping bump a stalled front north, into the forecast area this afternoon. Big jump in low level moisture with the boundary, so unlike the last few days there will be an abundance of deep moisture. Boundary layer humidity increases by some 20-30% compared to Mon afternoon leading to a significant increase in SBCAPE today. Much of the forecast area will see SBCAPE in the neighborhood of 1500-2000 J/kg with portions of SC seeing values over 2000 J/kg. Mid-level lapse rates increase a bit in the afternoon as heights fall slightly. There is a noticeable low level moisture gradient and partial thickness packing moving north into South Carolina in afternoon. This is likely where the first storms will develop.
These gradients lift north from late afternoon into the evening, steered inland by the afternoon sea breeze. Best storm coverage will be across most of the SC counties (away from the immediate coast) and inland NC counties. The more stable marine layer will limit convection across coastal NC counties. The 270-280 storm motion may lead to some convection moving across coastal NC in the evening, although it would be in a weakening state.
Area has been highlighted in a marginal risk by SPC and an isolated strong/severe storm cannot be ruled out, but with limited storm coverage and environmental parameters on the lower end of severe thresholds the overall threat appears to rather limited.

Coverage will be somewhat held back by the lack of strong forcing. The front itself is weak and the only PVA is shifted north of the area by midday as the ridge axis shifts east.
Diurnal heating and convergence where the sea breeze meets the front will be the main forcing mechanism for the initial storms.
Other storms will likely develop off the outflow from the first round, but coverage will be scattered at best. Temperatures will range from near normal along the coast, mainly due to the sea breeze, to slightly above normal inland.

Front lifts north of the area this evening leaving the region in the warm sector. Cannot rule out an isolated shower closer to the front overnight, although chances are slim. The lack of forcing and surface based instability suggests it will be a dry, but very warm night. Lows could be 10 or more degrees above normal.

SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/
A secondary surface low will be moving across NC on Wednesday, with attending cold front approaching our area during the day.
Primary window for scattered storms will be Wednesday morning through midday before subsidence from NVA and abundant dry air aloft (RH ~5% above 700mb) moves in from the west in the afternoon. Clearing skies Wednesday afternoon will allow temps to reach into low 90s, with MEX guidance hinting at a chance of 95F highs, as well as deep mixing leading to breezy wind gusts.
Cold front will move across late Wednesday with dropping dewpoints Wednesday night and lows in the low 60s.

Relatively quiet day Thursday with highs in the mid 80s and another day of breezy conditions. A second cold front looks to make its way through the Carolinas late on Thursday, with cooler and drier air behind it. Have lowered pops a little due to lingering dry air aloft, but have maintained slight chance for northern and coastal areas late Thursday due to front and PVA across NC. Low temps Thursday night will drop below normal into the mid to upper 50s.

LONG TERM /FRIDAY THROUGH MONDAY/
Quiet with below normal temps forecasted for Friday and Saturday as high pressure briefly builds in from the north.
Unsettled weather may return Sunday and Monday as increased moisture is advected over a mid-level ridge to the south and guidance shows a series of surface lows moving across the Southeast. Still a wide range of solutions shown in ensemble guidance so pops are rather limited with only a slight warming trend in the forecast.

AVIATION /07Z TUESDAY THROUGH SATURDAY/
High confidence in VFR through 18Z although patchy ground fog is possible across interior South Carolina. Scattered showers and thunderstorms will develop late afternoon and continue into the evening. Best chances will be at FLO and LBT with coverage between 30-40%. Sea breeze will result in east winds and stable marine layer for the coastal terminals. Storm motion will move storms that develop toward the coastal terminals, but the marine layer will limit any possible impact at CRE/ILM/MYR.

Extended Outlook...Low confidence in brief IFR/MVFR from storms through midday Wednesday. High confidence in VFR Wednesday night through Saturday.

MARINE
Through Tonight...Brief, weak northeast surge this morning with front slipping to the south. Sea breeze quickly dominates the wind field with onshore flow developing by early afternoon. The front returns north late in the day with southwest flow developing by midnight and increasing to around 15 kt in the predawn hours of Wed. Seas around 2 ft today build to 2-3 ft tonight once southwest flow sets up. Pretty chaotic mix of waves today with a northeast wind wave developing in the morning before a southerly wind wave takes shape tonight. A southeast swell will be present through the end of tonight.

Wednesday through Saturday...Southwest winds prevail Wednesday, with gusts up to 25 kts late afternoon/evening hours, before a cold front moves across the waters late Wednesday. Seas increase to 3-5 ft for Wednesday evening due to strengthened S wind wave mixing with 1-2 ft SE swell. Winds turn briefly offshore Wednesday night before SW flow returns Thursday ahead of a second cold front. West-northwest winds dominate Thursday night through Saturday, with strongest speeds around 15 kts Thursday night behind the front. Seas 3-4 ft Wed night through Thursday night lower to around 2 ft for Friday and Saturday.

ILM WATCHES/WARNINGS/ADVISORIES
NC...None.
SC...None.
MARINE...None.