Great Circle

Forecast & Marine Weather

The Great Circle, a human adventure...

Like all great success stories, Great Circle was created by visionaries. In 2010, the three founders decided to make their passion their job and combined their complementary skills of an experienced sailor, a renowned marine weather analyst and a brilliant marine scientist.

They soon decided to expand the team and create “Squid”, a piece of meteorological analysis software specifically adapted for navigation. Sensitive to the needs of skippers, Great Circle continues to develop by creating new innovative services to continually improve boat performance.

Great Circle works with most of the leading offshore teams and race management offices around the world, including the Vendée Globe, Volvo Ocean Race, Route du Rhum and America’s Cup.

In November 2021, The Nantes-based startup D-ICE Engineering integrates the marine weather forecast from Squid (Great Circle), please the full press release here in PDF.

Contact Details

  • Great Circle
  • Place de la Gare, 3
  • 1330 Rixensart
  • +32 (0)2 633 31 00

What we do

Our work is our passion so we are committed to bringing you the best possible service.

1. Squid

Squid is software that lets you download and view the GRIB weather files and does your routing (with the isochronic method). Squid can also display satellite images (visible imagery, infrared, water vapour and colour composite) and retrieve synoptic charts and observations (SYNOP, METAR and scatterometry).

2. Squid Mobile

The latest Great Circle application is Squid-Mobile! You can download it for free from the App Store (Apple) and Google Play (Android), and log in to your account to enjoy all your features. Download and try it now !

3. Best-Start

Best Start® is a decision support tool for the skipper to determine the best weather window to attempt to break a record. It can determine, to within three hours, the best starting point in the next ten days and assess the probabilities of beating the record.

4. Best-Sails

Best-Sails is a tool that allows for a very quick statistical study of the weather conditions and sea state on a given route. In addition, Best-Sails also analyses the sails usage statistics. The tool is based on highly detailed and high quality historical data.

5. Meteorological Support

Great Circle offers a meteorological support service to both skippers and race management. This consists of expert weather reports sent at regular intervals, as well as tools to help assess weather risks. Great Circle can also run pre-start weather briefings for your races / records / regattas / cruises.

6. Consultancy

Great Circle carries out specific meteorological studies, both in the marine field and on land. Our R&D team can tailor specific tools according to your needs.

They trust in us

Great Circle