South Sinai

South Sinai is the wedge of desert mountain that drops into the Red Sea between the Gulf of Suez to the west and the Gulf of Aqaba to the east, the two narrow arms of water that frame the peninsula and meet at the southern tip near Ras Mohammed. The coast is fringing coral from end to end. The reef terrace runs out from the shore as a shallow shelf, breaks at the reef edge, and drops in a near-vertical wall to several hundred metres of clear water — the geometry that put Sharm el-Sheikh, Dahab, and Nuweiba on the global dive map. The tide along this coast is semidiurnal with a small to moderate range. Mean astronomical range in the southern Red Sea is roughly 50 to 90 cm, modulated by the resonance of the Red Sea basin and constrained further at the head of the Gulf of Aqaba by the narrow throat at the Strait of Tiran. Spring tides around new and full moons push the swing toward the upper end of that band; neaps compress it. That is enough range to drain reef-flat pools, expose the inner reef to wading depth, and meaningfully change the swimming and snorkelling line on the shore-entry beaches at Naama Bay, Sharks Bay, and the Ras Mohammed lagoons. Wind, particularly the seasonal northerly that funnels down the Gulf of Aqaba, modulates water level by tens of centimetres independent of the predicted tide. The Khamsin transition seasons in spring and autumn bring stronger southerlies and noticeable surge along the Sinai coast. The Egyptian Hydrographic Department publishes the authoritative tide and water-level data for the Red Sea and Gulf of Aqaba; for any reef navigation or dive-boat operation, that is the source of record. Predictions across South Sinai stations on this site come from Open-Meteo Marine — a gridded global ocean model with timing accuracy of about plus or minus 45 minutes and height accuracy of roughly 0.2 to 0.3 metres, which on this small-range coast is a meaningful fraction of the total signal.