Accurate historical wind, waves, and weather data provide essential insights for planning your next passage or adventure. With Climate Data, you can access rolling averages from the past ten years of ECMWF ERA5 weather data, giving you the confidence to select the ideal time of year for your activity. This information helps you choose optimal passage routes, avoiding hazardous weather or choosing the best time to visit a location.

You can view the Map as a Wind Rose or Wave Rose.

A Wind Rose is a graphical tool that shows the frequency and direction of the average wind over a monthly period at a specific location. Select a Wind Rose to view the data set.

The length of the spoke radiating from the centre represents the frequency of winds blowing from that direction, with colour coding used to indicate wind speed and probability of the selected wind range. Select a coloured band to view the wind speed range, direction and probability.

A Wave Rose represents the distribution of wave height and direction at a specific location for the month.

Similar to a Wind Rose, a Wave Rose shows the frequency of waves coming from different directions and includes information on wave height, giving you a visual summary or typical sea conditions.

Both Wind Rose and Wave Rose include 10-year monthly average data at each location for:

Climate Data day and night values are available for wind, air temperature, rainfall, and cloud cover; other values are full-day averages.

To understand seasonal variability, set a zoom level and step across a season of several months to observe how the Wind and Wave Rose change over the period. To view winds and waves on the borders between regions, zoom in a level and step the months forward and back again to see how the data changes.

Crossing oceans in the correct season is prudent seamanship, avoiding cyclonic activity and other adverse conditions such as headwinds.

Using Climate Data well in advance of a planned passage will establish what month or months are best. Inside 30 days out, you could then start the departure planning/weather routing, which will be using the ECMWF ensemble, from here inside 10 days, using the actual models for departure planning/weather routing.

You are planning a kite foiling trip to Tahiti and want to know the best time to go for optimal wind conditions. Climate Data will show when the prevailing wind is best. Cross-referencing wind patterns with peak tourist seasons allows you to identify quieter months with great conditions. For example, you might find that the best winds for kite foiling occur just outside the traditional tourist season, allowing you to enjoy fewer crowds while still getting excellent weather.

This means that Climate Data is updated each month with the most recent information. Unlike Pilot Charts, which can be unreliable due to outdated data, the effects of the changing climate are always represented in what you can see.

Wind and Wave Roses are available at pre-set locations for each zoom level worldwide on a grid basis. Adjust your zoom level and pan on the map to identify your desired location for a detailed view.

Wind and Wave Roses show a full 24-hour average for each day in the calendar month.

ECMWF ERA5 data is a global historical weather and climate dataset produced by the European Centre (ECMWF). It is part of their Copernicus Climate Change Service reaanalysis products

What "reanalysis" means

ERA5 is create by combining

The models fills in the gaps between observations, and ensures all data is consitent accross time and space. The result is a complete global record of the atmosphere. However this is done at 31km resolution. At this resolution, you cannot expect the climate data to accurately account for sea breeze or geographic effects, but it will accurately represent the average synoptic winds.