Course is a projection, not the sailing instructions — the RC sets the real course. Mark is drawn 0.5 × course length upwind of a fixed race-area centre (40.6694, −74.0295) that reproduces the usual G1 / G11 / G9 / R32 / Y-A placements. Close-hauled angle is an adjustable assumption, not a measured Melges 24 polar. Centre E/W nudges the whole course across the harbour: weeknights default 125 m west to match observed racing, Saturdays to the buoy-derived centre. Saturdays use the 1–4 pm window, weeknights 5–8 pm. NYHOPS forecasts only 48 h ahead, so Saturday has data from Friday onward.