Get the long-awaited swell map in the 10.1 for iOS


In the middle of this summer outdoor season, we updated the for iOS and iPadOS with the long-awaited Swell Map feature. The map has high resolution and the most accurate and longest wave forecast possible up to 10 days. It will be useful for everyone who surfs, but also for sailors, kayakers, and literally everyone who is into water sports.

Swell Map and swell forecast in the for iOS

I’m new to the outdoors. What is a swell and a Swell Map in

Swell is a collection of waves in the ocean generated by specific conditions like a storm, so they form far away from the coast. Swell, then, can travel a long way to the beach (think like 2000 miles offshore). The swell has four major parameters: direction, size (or height), period, and energy — the ones that determine how surfable is the swell.

The swell map is a visualization of the swell forecast from the MFWAM (Meteo France Wave Model) weather model. It is a global model, which means it gives a forecast for the whole world at once. It is also the best and most accurate model available for wave forecasting and is now available in the for iOS and iPadOS.

The main features of the MFWAM weather model are the following:

  • Resolution (grid): 9.25 km (5.74 mi) or 1/12 degree
  • Depth (period): 10 days
  • Step: 3 h
  • Updates: 1 time a day (every 24 h)

How to read Swell Map in

1. Take a look at the colors on the map. It indicates the swell size or the height of the waves: from 0 (blue) — no waves, to 3.2 meters (magenta) — very big waves.

2. Zoom the map to the region you want to get a forecast for. It could be your favorite spot or the closest one to your current location.

The white triangles on the map show the direction of waves — that is FROM where the waves are coming. For example, for the popular Carmel Beach surf spot in Monterey, California, USA, the direction of the swell is west-southwest (WSW) on the screen right next. So reading swell direction is the same as reading wind direction.

Swell Map in the for iOS

3. Click on any point on the map to get an accurate swell forecast if you don’t need or don’t know the exact spot. It shows you the coordinates of the spot also in degrees: N 27.2612, W 115.62.

Swell Map in the for iOS

4. If you still need to find a spot for surfing, open the Weather Map's Extra Setting to find the surf spots closest to you faster by hiding all other types of spots.

Swell Map Extra Settings in the for iOS

5. Go to the spot screen clicking on it to get the most detailed forecast, including swell's other basic parameters, besides the direction:

  • Swell size (or swell heigh). An average height of 1/3 of the highest waves in the swell (series of waves). For an amateur surfer, the size of the good wave is from 1 meter, m (3.5 feet, ft) to 3 m (10 ft).
  • Swell period. The time between successive waves, or swell frequency. The longer the period, the faster and more powerful the waves. 8 seconds (s) — normal surfing, 11 s — good, 14+ s — great (pure groundswell).
  • Swell energy. The power of waves is formed by a combination of their size and period. Bigger waves plus longer periods — more power. 100 kiloJoule (kJ) — surfable waves at many breaks, 200–1000 kJ — punchy waves, 1000–5000+ kJ — heavy and dangerous waves at some breaks.

Swell forecast (wave forecast) in the for iOS

Swell forecast (wave forecast) in the for iOS

Where to find Swell Map in

Open the Weather Map from the Home screen of the app. Then select "Swell" in the weather parameters slide under the wind icon. At the same time, the map's weather model will change to MFWAM.

Home Screen of the for iOS


Learn how to read surf forecast from the article in the blog, and read more posts on surfing in “The collection of articles about surfing in 2021.”


The feature is available in the version 10.1 for iOS from July 21, 2021. The feature is also available in the Android version from March 11, 2021.

Text: Ivan Kuznetsov, an outdoor journalist, editor and writer from the Dolomites, Italy, and Karelia, Finland, with 10 years of professional experience. His favorite sports are hiking, cycling and sauna. Read his other articles

Share:   WINDY.APP Facebook   WINDY.APP Twitter
Subscribe to Meteo Textbook 
Take previous lessons on the website

Related News

This website uses cookies to improve your experience. If you continue to browse this site, you are agreeing to our Privacy Policy and Terms of Use.