Weather: GRIB files and forecasts
This chapter explains how to get and read weather forecasts in NavimetriX: what a GRIB file is, how to choose a model, download it, manage the list of your files and display wind, pressure, rain, waves and currents on the chart. It also presents the meteogram, which shows how the forecast evolves at a single point, and historical weather, which lets you replay a past passage with the weather it actually had.
- Understanding GRIBs and choosing a model
Beginner
What a GRIB file is, what run, step and grid spacing mean, the model families (global, regional, ensemble, waves, currents) and how to choose.
- Download a GRIB
Beginner
Draw the area on the chart, choose the model, duration, step and parameters, keep an eye on the file size, or let the magic wand suggest the models.
- Managing the GRIB list
Beginner
The GRIBs tab: display a file, update it when a new run is published, automatic download, rename, delete, import and export.
- Displaying forecasts on the chart
Beginner
Choose the displayed parameter, set barbs, particles, color map, iso areas, isobars, land mask and transparency, and read the values under the target or the cursor.
- Meteogram
Expert
The hour-by-hour table of the forecast at the center of the chart: wind, gusts, pressure, temperature, rain, clouds, CAPE, snow, current and waves.
- Waves and sea state
Expert
Display wave height, period and direction, wind sea and swell next to the total sea, the steepness of the sea, and adjust their display.
- Currents
Expert
Display the currents of a GRIB or the SHOM tidal current atlas, as arrows or particles, and use them in routing.
- Historical weather
Expert
Load the past weather of ECMWF IFS 0.25° for an area and a period, up to today, to replay a passage or study a situation.