Moonlight Beach dive visibility forecast
Overberg coast, Grootbaai, east of Hangklip lighthouse
Issued Thursday 5 November 2026 at 16:10 SAST. Next run due by about 19:10 SAST. Live data: api.theviz.co.za.
Moonlight Beach, Overberg coast, tomorrow, Friday 6 November 2026: median underwater visibility 6.1 m (80% interval 3.8–10.0 m), conditions touch and go, 46% chance of reaching diveable in the best daylight hour. Limiting factor: wind on the surface. Best window 06:00–13:59.
Moonlight Beach, Overberg coast, Saturday 7 November 2026: median underwater visibility 4.5 m (80% interval 2.5–7.9 m), conditions not diveable, 1% chance of reaching diveable in the best daylight hour. Limiting factor: entry and exit. No diveable window during daylight.
Moonlight Beach, Overberg coast, Sunday 8 November 2026: median underwater visibility 3.2 m (80% interval 1.7–5.8 m), conditions not diveable, 0% chance of reaching diveable in the best daylight hour. Limiting factor: entry and exit. No diveable window during daylight.
Moonlight Beach, Overberg coast, Monday 9 November 2026: median underwater visibility 3.8 m (80% interval 2.0–6.9 m), conditions touch and go, 49% chance of reaching diveable in the best daylight hour. Limiting factor: entry and exit. Best window 06:00–19:59.
Moonlight Beach, Overberg coast, Tuesday 10 November 2026: median underwater visibility 5.0 m (80% interval 3.0–9.1 m), conditions touch and go, 0% chance of reaching diveable in the best daylight hour. Limiting factor: current. Best window 06:00–19:59.
Moonlight Beach, Overberg coast, Wednesday 11 November 2026: median underwater visibility 6.1 m (80% interval 3.6–10.8 m), conditions diveable, 97% chance of reaching diveable in the best daylight hour. Limiting factor: entry and exit. Best window 06:00–19:59.
Probabilistic water-clarity forecast for Moonlight Beach (Overberg coast, Grootbaai, east of Hangklip lighthouse), a dive site near Cape Town, South Africa. Visibility is modelled from six days of swell and wind history rather than measured, because clarity lags the weather that stirred it.
Three-day visibility forecast for Moonlight Beach
| Day | Median viz | 80% interval | Conditions | Chance of reaching diveable | Limiting factor |
|---|---|---|---|---|---|
| Tomorrow, 6 Nov | 6.1 m | 3.8–10.0 m | Touch and go | 46% | Wind on the surface |
| Saturday, 7 Nov | 4.5 m | 2.5–7.9 m | Not diveable | 1% | Entry and exit |
| Sunday, 8 Nov | 3.2 m | 1.7–5.8 m | Not diveable | 0% | Entry and exit |
| Monday, 9 Nov | 3.8 m | 2.0–6.9 m | Touch and go | 49% | Entry and exit |
| Tuesday, 10 Nov | 5.0 m | 3.0–9.1 m | Touch and go | 0% | Current |
| Wednesday, 11 Nov | 6.1 m | 3.6–10.8 m | Diveable | 97% | Entry and exit |
About Moonlight Beach
| Region | Overberg coast, Grootbaai, east of Hangklip lighthouse |
|---|---|
| Coordinates | -34.3773, 18.8270 |
| Best realistic visibility | 8 m |
| Modelled working depth | 8 m |
| Forecast horizon | 7 days, hourly. The last four are an outlook |
How to read this forecast
The median is the middle of the modelled distribution: half the ensemble members came out clearer, half murkier. The 80% interval is the spread between the 10th and 90th percentiles. A wide band means the weather models disagree about the swell or wind that will stir the bottom, not that the site is unpredictable in itself.
P(diveable) is the share of ensemble members whose worst safety gate still clears at the best daylight hour. The limiting factor names which gate binds first: entry and exit, bottom surge, current, wind or surface chop. A site can have beautiful water and still be undiveable because the entry is unworkable.
For the full hourly distribution, the fan chart and the uncertainty breakdown, open the live forecast. Method and inputs are set out in the methodology.
Water clarity on theviz is forecast from swell and wind history. It does not measure it, and it is not navigation or dive-safety advice. Conditions change fast; check locally, dive within your training, and verify marine protected-area boundaries before spearfishing.