Partly cloudy

Partly cloudy describes a marine forecast in which cloud covers part of the sky but leaves regular clear breaks, so sunshine and shade alternate over the water. It usually indicates fair to changeable conditions rather than overcast weather, with enough cloud to influence light, temperature, and local wind effects.

For boaters, partly cloudy skies generally mean good visibility and usable daylight, but conditions can still vary across a passage. Cloud streets or building cumulus may signal shifts in Wind Speed, isolated Rain, or increased Cloud Cover later in the day. Sailors should watch the horizon and compare observations with the forecast before committing to reefs, watch schedules, or exposed anchorages.

In PredictWind forecasts, partly cloudy conditions are best assessed alongside wind, rain, temperature, and satellite-style cloud layers rather than as a single comfort indicator. Comparing several Forecast Model outputs helps identify whether the cloud is benign fair-weather cumulus or part of a developing change that may affect routing or departure timing.