Historical swell reports and spot statistics

When planning a surf trip, it can be challenging to predict wave conditions for the upcoming months. To gain insight on wave patterns, wind direction and other key information, it’s beneficial to analyze past data.
Swellarchive.com is a valuable resource that offers wave and wind information for a wide variety of surf spots around the globe. Our website allows you to easily compare different surf spots for your planned travel period and examine wave patterns for specific locations over the past several years. This is made possible by utilizing archived simulation data from the GFS-Wave model between 1980 and 2021. Use our website to plan your next surf trip and make the most of the waves.

Here you can find a description of the main parts of the website and wath’s the shown data means for the conditions at the beach.

How-to

Analyse spot

With analyse spot you can find all available data for over thousand spots around the globe. The content is seperated in two sections. Statistical data for swell and wind where you can learn how conditions coud be for a specific season of the year. Or you can look at a the detailed historical surf forecast for a specific month between 1980 and 2018. Here you can find some examples for the statistic view for

Compare surf spots

With compare surf spots you can compare the wave and wind information for up to four surf spots. You can display the detailed historical surf report for a month between 1980 and 2018. Or you can compare surfing locations based on statistical wave heights and wind directions. The number of days with suitable waves and wind conditions can also be output and compared.

Diagrams

The surf report plot depicting historical information such as the swell height and direction, swell period, and wind speed and direction for each day of the month. The bars denoting the swell height are color-coded based on the corresponding swell period, ranging from light blue to dark blue. Similarly, the arrows representing the wind direction are sized and colored according to the wind speed.

This wind rose plot provides a concise overview of wave characteristics, particularly wave height and wave direction, based on averaged data collected at a specific location. The plot is divided into sectors, each corresponding to a specific range of wave directions (e.g., North, East, South, West) and varying in size based on the frequency or proportion of observations within that sector.

  • Wave Height: The length of the radial lines extending from the center of the plot outward represents the average wave height for waves originating from a particular direction. Longer lines indicate higher average wave heights, while shorter lines represent lower wave heights.

  • Wave Direction: Each sector is labeled with the compass direction it represents (e.g., N for North). The direction from which the waves predominantly arrive is indicated by the longest radial line in that sector. This provides a clear visual representation of the prevailing wave direction.

By examining this wind rose plot, users can quickly grasp the dominant wave direction and the range of wave heights typically experienced at the location, helping them make informed decisions related to water-based activities and navigation.

Monthly Wind Conditions

This bar plot provides a succinct visual representation of the average wind conditions categorized as „good“ and „bad“ for each month of the year. It consists of twelve bars, one for each month.

By examining this bar plot, users can quickly identify the months when good wind conditions are most prevalent and when they are less favorable, helping them plan their surf trips throughout the year.

Monthly Swell Conditions 

This bar plot shows the average swell conditions categorized into three types—wind swell, ground swell, and no swell—for each month of the year.

  • Wind Swell: The height of the green bars represents the average occurrence of wind swell conditions for each month. Wind swell typically results from local winds and is characterized by shorter, choppier waves. These conditions may be suitable for some water activities like bodyboarding.

  • Ground Swell: The height of the blue bars indicates the average occurrence of ground swell conditions for each month. Ground swell is created by distant storms and tends to produce longer, more organized waves. Surfers often prefer ground swell conditions for optimal wave riding experiences.

  • No Swell: The height of the gray bars denotes the average occurrence of no swell conditions for each month. This signifies periods when the ocean experiences minimal wave activity, which might be suitable for SUP or snorkling.

Swell data

What mean the different data that are shown in the graphs or the how good surf conditions are calculated. Here is a short discription of all used data.

Swell Height – The value of the significant wave height is used for the swell height. The significant wave height was historically chosen to correspond to the intuitive visual measure of the wave height by seafarers. It is about 1.25 times the average wave height and correspond usually with the highest wave of a set.

Swell Period – Swell period is the time interval between two consecutive wave peaks (crests) at a  fixed point, and it is given in seconds. The period of a swell can be crucial whever a swell produces nice surf conditions at a certain beach.

Swell Direction – Swell direction indicates the compass direction from which the dominant swell waves are coming. It’s expressed in degrees, with 0 degrees representing north and 180 degrees representing south.

Wind Speed – Wind speed refers to how fast the air is moving horizontally. It’s typically measured in units like knots, meters per second, or miles per hour and is important for assessing how wind affects wave conditions.

Wind Direction – Wind direction specifies the compass direction from which the wind is blowing. It’s also expressed in degrees, with 0 degrees being north and 180 degrees being south.

Swell Quality – Swell quality is a subjective assessment of how well-formed and clean the waves are. High swell quality indicates well-shaped, organized waves suitable for surfing or other water activities.

Surf Consistency – Surf consistency describes how regularly and predictably waves are breaking. A consistent surf spot has waves breaking at regular intervals, making it easier for surfers to catch waves.

Good Wind Conditions – Good wind conditions refer to favorable wind patterns for surfing at an specified spot. Generally, light and offshore winds (blowing from the land towards the water) are considered ideal, as they create clean and well-shaped waves.

Sources

We use different sources for the historical swell and wind data: