Marine Weather and Tide Forecast for Atlantic Beach, SC

NEAR TERM /THROUGH FRIDAY/
Front stalled across northern SC and the adjacent coastal waters will linger into this evening before lifting north as a warm front.
Moisture pooling along the stalled boundary in northern SC and surface heating has SBCAPE around 1500 J/kg this afternoon.
Convergence along the sea breeze in this environment is producing showers and thunderstorms along the southern edge of the forecast area. This activity will continue for the next several hours with both the sea breeze and outflow kicking off additional storms. Think activity will continue spreading into the ILM forecast area with inland SC favored. As time goes on some of the SC activity will expand over portions of NC, although the best convection is likely to remain across SC. The overall environment across NC, both at the surface and aloft, is less favorable.

Convection may persist a bit longer than diurnal storms typically do, a result of some weak PVA ahead of a sheared shortwave in eastern GA/western SC. The front lifts north later this evening, but the boundary itself is so weak it will be hard to discern from any convective boundary remains or the sea breeze. Once it pushes north low level southerly flow will increase boundary layer moisture and the light to calm boundary layer winds will likely lead to some good fog, especially for areas that have seen good rain in the last 24 to 36 hours. Have fog in the grids/forecast but could be a case of needing to hit it harder in later updates. Lows will end up 7-10 degrees above normal.

Forecast area will be in the warm sector Fri with SBCAPE across the area generally 1000-1500 J/kg. Southeast synoptic flow around the west side of the high will limit convergence along the sea breeze and the lack of strong triggers or support aloft will limit storm development. There should be enough instability for diurnal convection with outflow encouraging more storm development, however coverage will be limited by the marginal nature of the environment.
Despite decent SBCAPE, low and mid-level lapse rates are marginal and there is dry air present. Best chances will be across inland areas, around and just after peak heating. Temperatures around normal closer to the coast and slightly above normal inland.



SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/
A decent mid level short wave and associated convection will be entering the area Friday evening from the west but as is usually the case will fade withing site of the coast. A second shortwave and associated front moves across late Saturday and into the evening hours with another round and perhaps a broken line of convection. Likely pops reside across the area at this time but may need an adjustment downward especially Saturday morning. Highs will be in the somewhat muggy lower to middle 80s Saturday while much cooler and comfortable behind the system Sunday in the middle 70s.



LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/
The mid level trough that brings the cooler conditions late in the weekend and into early next will be replaced by a somewhat strong mid level ridge across the southeast. It appears this setup is similar in nature to the pattern a week or so ago where there was excellent moisture/convection in the Tennessee Valley but just cant make much progress eastward. Long story short the forecast is dry. In the seemingly well established pattern probabilistic and deterministic guidance is in excellent agreement in regards to temperatures. The headline of which will be middle to upper 80s for highs late in the period.



AVIATION /19Z THURSDAY THROUGH TUESDAY/
Expected isolated to scattered convection developing during the next few hours, mainly across inland SC, along the sea breeze and continuing into the evening hours. Some of this activity could affect LBT later in the afternoon/evening, but best chances for MVFR/IFR conditions with any storms will be at FLO.

Front stalled in the area today will lift north later tonight into Fri as a warm front and the resulting light southerly flow will lead to an increase in low level moisture. MVFR/IFR visibility and ceilings will be possible at all sites after midnight. Boundary layer winds are light enough that dense fog could be an issue in some areas, especially those where rain fell in the last 24-36 hours.

Extended Outlook.. MVFR/IFR possible at inland terminals Friday afternoon/evening and at all terminals Friday night and Saturday. VFR returns Saturday night through Monday.

MARINE
Through Friday...
Gradient across the waters remains ill-defined as surface high continues drifting east. Winds will remain 10 kt or less with the only exception the potential for 10-15 kt along the immediate coast this afternoon/evening due to the sea breeze. The sea breeze will have less influence tomorrow due to the larger scale southeast(onshore) flow. Seas around 2 ft into Fri with potential for 2-3 ft later Fri as light onshore flow becomes established. Seas will be a mix of an easterly swell and an east to southeast wind wave with the swell being slightly more dominant.

Friday Night through Tuesday...
The marine forecast offers really nothing unexpected as we near May and any frontal systems that do make it across have little in the way of cold air advection thus weaker winds. This will be the case Sunday when northwest to northeast winds around 15 plus knots are the highest of the forecast period. Before this a southwest flow will be in place in the standard range of 10-15 knots. For early next week a return flow develops but nothing is moving fast and not until Wednesday or so will we see a full return to south to southwest winds.

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