Trace the route on the map and get weather forecasts
Ekynavy marine weather: wind, waves, tides, swell and pressure in real time
Planning a passage without reliable marine weather means sailing partly blind. Ekynavy brings together in one place all the data you need to decide before leaving and fine-tune during the voyage.
Table of contents
11 aggregated weather models, 6 leading forecast centres
Ekynavy aggregates 11 forecast models from leading meteorological centres so that, depending on your sailing area, you always get the most relevant level of precision available.
Global models — crossings and trends
- ECMWF IFS (European Centre) — 9 km, worldwide, 10 days
- GFS Global (NOAA, USA) — 25 km, worldwide, 16 days
Regional models — coastal precision
- Arpège Europe (Météo-France) — 10 km, 4 days
- AROME France — 1.3 km, 2 days
- AROME France HD — 0.75 km, 2 days, finest detail on French coast
- ICON Europe (DWD, Germany) — 7 km, 7 days, North Sea and Baltic
- UKMO (UK Met Office) — 2 km, 7 days, Channel and British Isles
- HRRR USA (NOAA) — 3 km, 2 days, US coastline
- NBM USA (NOAA) — 2.5 km, 11 days, USA
- GEM Americas (Environment Canada) — 2.5 km, 10 days, Canada and Caribbean
Marine data and tides
- Open-Meteo Marine API — waves, primary and secondary swell, currents
- WorldTides — minute-level tides, near-global coverage
- SHOM — optional official French nautical charts layered over the weather
- Windy — real-time animation engine, 72 h to 7-day timeline depending on model
💡 The tool above is free to use, no sign-up required. The same data is available offline in the Ekynavy app via GRIB files downloaded before departure.
How to use the marine weather map
The map is designed for simple use: pick a model, show the layer you care about, then scrub through time to see how conditions evolve across your sailing area.
Pick the right model for your zone
- French coast → AROME France HD (finest detail up to 48 h)
- Atlantic crossing → ECMWF IFS or GFS Global (long horizon)
- Channel / Ireland / British Isles → UKMO (2 km)
- Baltic / North Sea → ICON Europe (7 km)
- US East Coast / Caribbean → HRRR USA, NBM USA, GEM Americas
Parameters available from the menu
- Wind at 10 m and gusts
- Significant wave height
- Period and direction of primary and secondary swell
- Ocean currents
- Sea and air temperature
- Mean sea level pressure
- Precipitation
💡 A moderate wind with crossing swell or contrary current doesn't produce the same sea as a plain wind figure. Always cross-reference at least two layers before heading out.
Scrub through time
The horizontal bar at the bottom is the weather timeline. Scrub hour by hour to watch a front arrive, a low deepen, a thermal build up or a rain band shift. The wind layer colours follow the Beaufort scale — green light breeze, yellow fresh, orange strong breeze, red gale.
Reading a marine weather bulletin and wind strength
Thresholds to remember for recreational sailing
- 20 knots sustained — demanding sailing, sail reduction, attentive crew
- 25 knots sustained — technical conditions for many boats and crews
- 33 knots (Beaufort force 8) — heading out is rarely trivial
Mean wind vs gusts
On exposed coasts, relief features or enclosed waters (Basque coast, Gulf of Lion, Corsica, Maritime Alps…), gusts can significantly exceed the mean. Ekynavy always displays the gust next to the mean wind on the map.
💡 Always compare mean wind and gust: the gap measures the risk of technical conditions more than a single value.
Multi-model comparison
When several models cover the same area, their convergence is the best indicator of confidence:
- AROME HD + ECMWF + UKMO agree → reliable forecast
- Sharp divergence → uncertain situation, extra caution and margin
Which weather model should you pick for your passage?
Not all models serve the same purpose. The right reflex: pick based on zone, forecast horizon and type of sailing.
Global vs high resolution
- Global (ECMWF IFS, GFS Global) → overall view, multi-day trend, departure window for a crossing.
- High resolution (AROME HD, UKMO, HRRR, ICON) → local effects, gusts under relief, straits accelerations, harbour approach.
Comparison table of the models available in Ekynavy
| Model | Type | Area | Horizon | Recommended use |
|---|---|---|---|---|
| ECMWF IFS | Global | Worldwide | ≤ 10 days | Long passages, weather windows |
| GFS Global | Global | Worldwide | ≤ 16 days | Transats, medium-term trend |
| Arpège Europe | Wide regional | Europe | ≤ 4 days | Bridge coastal/offshore |
| AROME France | High resolution | France | ≤ 2 days | Coastal sailing, day sails |
| AROME France HD | Very high resolution | France | ≤ 2 days | Complex zones, gusts, approach |
| ICON Europe | Regional | North / Baltic | ≤ 7 days | Northern European sailing |
| UKMO | High resolution | UK / Channel / Ireland | ≤ 7 days | Channel, South English coast |
| NBM USA | Fine regional | United States | ≤ 11 days | US coastal sailing |
| HRRR USA | Very high resolution | United States | ≤ 2 days | Short-term near-shore detail |
| GEM Americas | Wide regional | Canada / Caribbean | ≤ 10 days | Western Atlantic cross-check |
💡 For a 3-4 day crossing: pick a global model for the overall trend, then a regional model as you approach your arrival coast.
GRIB file vs online model: which should you pick?
GRIB file — offshore and out of coverage
Before departure, Ekynavy lets you download a GRIB based on the model best suited to your zone (ECMWF, GFS, AROME, ICON, UKMO, GEM) with only the variables that matter:
- Wind, gusts, pressure
- Waves and currents
- Compact (~200 KB for 72 h over a mid-size area)
- Readable offline in OpenCPN, zyGrib or qtVlm
Ekynavy offline — more than just GRIB
Before leaving, you can also sync inside the app all the data useful to your passage, which stays consultable without network:
- Wind and weather graphs
- Tides at your stopover points
- Info tied to your weather points and route
Online model — coastal with 4G
The map above stays the best solution as long as you have a stable connection: fresher data, easier multi-model comparison, quick view of evolving weather systems.
💡 Coastal with stable 4G → online model. Beyond 10-15 NM offshore or for a crossing → data synced in the app + a GRIB downloaded just before casting off.
How reliable are marine forecasts over time?
By horizon
- 24 h — very useful for deciding on departure, arrival or a coastal passage
- 72 h — relevant for planning a crossing or scoping a weather window, wider uncertainty
- Beyond 5 days — qualitative trend, insufficient for pinning a precise time
High resolution vs global
For a multi-day passage, the good practice is to cross a global model (ECMWF, GFS, GEM) for the overall trend with a regional model (AROME HD, UKMO, ICON, HRRR) for the final approach or the arrival coast.
⚓ Safety rule: before casting off, always consult an official bulletin from your area's weather service (Météo-France, UK Met Office, MeteoSwiss, AEMET…). These bulletins remain the legal reference in case of a dispute with an insurer, a port of refuge or the maritime authorities. The Ekynavy map complements these bulletins — it doesn't replace them.
💡 Going further: Reading marine weather in 2026: BMS, GRIB and bulletins explained