How to read a sailing window

MARLOG’s sailing window is a wind outlook on the Home screen. It shows up to 12 hourly readings from the available forecast, starting with the current hour. Use it to understand the wind trend, alongside the detailed Forecast screen.

What the bars show

Each bar represents one hour. Its height follows wind speed in knots: taller bars mean stronger wind, not a better time to sail. The display limits very short and very tall bars so they fit in the card; check the forecast values for the actual speed.

What the colours mean

Lime marks the current hour, whatever its wind speed. Later hours at 18 knots or above use amber. Other future hours are muted. These colours identify the current position and stronger wind; they are not a green, amber and red departure rating.

Reading the example

In the illustration, the current reading is 12 knots and the peak is 20 knots at 12:00. The lime bar marks now; the amber bars mark later readings of at least 18 knots. The caption describes the peak and whether the wind eases after it. These are invented example values, not a forecast for a real place or date.

Choosing your hour

Height tells you less than period. A metre of long-period swell is a comfortable ride; a metre of short, steep chop on the nose is a wet, slow slog. When two hours look alike on the bars, open the forecast and compare the wave period — the longer one wins.

On the Aegean in summer, respect the afternoon. Thermal winds build through midday and the meltemi does not read forecasts politely. A light morning and a strong afternoon are not two options — they are one option and a warning.

Prefer an hour when the wind is easing rather than building. Leaving as the bars fall means conditions improve while you are out; leaving just before they rise means the wind arrives once you are already committed.

Check the wider forecast

The Home bars use wind speed alone. Waves, wave period, gusts and other conditions belong in the wider forecast review; they are not combined into the height or colour of these bars. A muted bar does not mean conditions are safe, and a taller bar does not recommend a departure hour.

Before you trust any hour, check the alert line. A sea-state alert overrides a pretty strip of bars: the chart shows light wind, the alert says the sea disagrees somewhere on your track. The alert wins.

When data is unavailable

If no hourly wind readings are available, MARLOG shows placeholder bars without a wind-summary caption. A placeholder is not a calm-weather forecast.

MARLOG is a discovery, learning and reference app. Always check official marine forecasts and warnings and carry official charts. The sailing-window display does not replace those sources or the skipper’s judgement.

Explore the MARLOG Forecast features for the wider weather picture.