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Optimize Weather Data Downloads

Download faster, store less, sail better.

This tutorial guides you through configuring your GRIB cache zone. By limiting the geographic download area, you reduce download time, storage space used and resource consumption.

Step 1: Access Cache Settings

From the main screen, open the menu and select "Offline Cache". You'll access the weather data download settings.

Cache settings with zone section

Step 2: Understand the Cache Zone

By default, the zone is set to "Global" (worldwide coverage). This means weather data covers the entire world, which can take longer to download and use more space.

Global zone with custom selection button

Step 3: Define a Custom Zone

Tap "Custom Selection" to define your own zone. The app switches to the map with a selection rectangle.

Zone definition overlay on the map

Step 4: Adjust the Zone on the Map

Drag the corners of the rectangle to adjust the zone. The coordinates (North, South, East, West) and area are displayed in real-time. You can also move the map to reposition the zone.

Tip: A smaller zone = faster downloads and less storage used.
Adjusted zone with coordinates and area

Step 5: Confirm the Zone

Once satisfied with your selection, tap "Confirm". The zone is saved and coordinates are displayed in the cache settings.

Confirmed zone with details

Step 6: Alternative - Global Zone

If you plan to sail in various areas or make long crossings, you can return to the global zone by tapping the "Global" button.

Advice: Use global zone for ocean crossings, and a custom zone for coastal sailing.
Global zone option

Step 7: Select Weather Models

Choose weather models to download (GFS 0.25°, GFS 0.50°, ECMWF) and adjust the number of forecast days with the slider. The estimated size is displayed for each model.

Weather models selection and forecast days

Step 8: Download the Data

Tap "Download" to start the download. A progress bar shows the advancement. Once complete, models display a badge indicating they are cached.

Download in progress
Download complete

Step 9: View Data on the Map

Close the cache panel and return to the map. Weather data (wind, gusts, etc.) now displays in your cache zone. You can navigate through time with the timeline.

Map with GRIB data displayed

You're Ready!

Your cache zone is configured. Updates will be faster and consume fewer resources. Don't forget to download data before heading out to sea!

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