Celsius

Celsius (°C) is the temperature scale commonly used in marine forecasts, instruments, and voyage planning outside the United States. It expresses air and sea temperatures relative to water freezing at 0°C and boiling at 100°C, helping crews interpret forecast conditions, onboard sensor readings, and weather model outputs consistently.

For boaters, Celsius affects clothing, watchkeeping, engine-room checks, provisions, and safety decisions such as hypothermia risk after immersion. Comparing forecast Temperature with Sea Temp helps assess comfort, condensation, fog potential, and crew exposure, while sudden changes can signal frontal activity or changing air masses relevant to passage planning.

PredictWind displays Celsius as a selectable unit in forecasts, tables, and maps, including high-resolution Air Temp Maps and offshore GRIB downloads. Using the same units across the crew, chartplotter, and weather apps reduces confusion when briefing conditions or making routing decisions at sea.