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About Marineweather


Welcome to Marineweather.co.nz - New Zealand's Advanced marine forecasting website.

Marineweather.co.nz utilses the same raw wave model data that many swell forecasting websites use - Buoyweather.com being an example.

But this is where the similarities stop.


Marineweather runs this data through a complex set of software and forecasting applications which generate a forecast up to 2000 times greater resolution than other open ocean forecasts on the internet.

Our powerful system models the affect on swell approaching the new zealand shoreline.
Sea floor Bathymetry, headland and Island swell blanketing, as well as sea floor depths and refraction are taken into account to produce our forecasts.

All of these factors determine wave size and strength at marineweather.co.nz's hundreds of shoreline forecast points around New Zealand - This is the most important data for marine enthusiasts.

Our forecasts are constantly monitored for accuracy using LIVE beach cameras at a dozen key points around New Zealand, along with real-on-the beach surf reports daily.


This allows our team to compare forecast data with realtime weather and swell events and continually adjust these for unparaleled detail and accuracy.

Looking to advertise you brand or business?

Marineweather.co.nz enjoys a loyal user base of boaties, fishermen, surfers, sailers, kiteboarders recording several thousand user visits per day - contact us today and get your business or brand out there.


We have just launched our Brazil marine weather forecast site - swellXL. Covering over 320 beaches in Brazil, it is the perfect tool to find detailed Brazil marine information.

FAQ's


 

How to use the forecasts?
Use the selector map (top left) to Navigate the local area.
Click on the spot name or yellow graph icon to select the wave, wind and tide forecast for that spot.
Run your pointer over the graph to view a detailed data box and to animate the Wavemap.
Click each the graph bars to pop-up the detailed wave, wind and period chart for that time.

Where does this data come from?
The United State Weather Service NOAA.
This site utilises the same raw data source used by Bouyweather, Swellmap and many other marine forecast websites.
From there this data is run through a complex set of software and applications which model and forecast how the swell will behave the closer it gets to the New Zealand shoreline. This is where we differ from the sites mentioned above. Massive computer power forecasts marine conditions taking into account ocean floor bathymetry, Islands, Reefs, bars and forecasts how the open ocean ground or winds swell will be affected by those elements.

How reliable is this forecast?
This process can forecast a swells arrival to the hour. It can also miss a quick generating winds swell. Use it as a core forecasting tool - use live cams, surf reports and your eyeballs to back up that data.
How are waves made?
By wind and friction across the oceans surface. The stronger and longer the wind blows the bigger and more powerful the waves. The distance which winds are present over the surface of the ocean determines the power of swell.

What is Peak Face Height?
Face height is marked as dark blue on the forecast graph.
This represents the largest shoreline set wave you can expect for that time at the chosen location.
Please note - the average wave face height will be smaller than peak face height.

What is Chop Height?
Here's an example: Say we have a southwest groundswell which was created by a deep southern ocean low pressure system below Australia. It is sending a strong 2 metre swell to NZ's West Coast. Then we have also have a 30kt Easterly wind blowing offshore at the same time. If you take a boat one kilometre offshore you will not only have a surging southwest groundswell heading toward shore, but you will also have a sizable wind chop coming from shore. Chop height represents the height of the wind-swell. These chop heights can reach several metres when the shoreline wave heights are flat, so this is particularly relevant to fisherman especially on the East Coast of New Zealand.

What is Ocean Swell?
This is the deep ocean swell height offshore.

How does period affect size?
Period is everything in determining size and power of shoreline surf. Long period swells (like 13 seconds) will pack more size and more punch when compared to a short period wind swell (like 4 seconds). Spend some time on the site and start to notice the relationship between wave heights and period. A surfer should place as much importance on period as he or she does on swell height.

What is fetch?
Fetch is the distance component of the wave making process. When wind blows over the ocean for thousands of miles in one general direction it is said to have a large fetch. Look as isobar charts and the line which connect points of equal pressure. these lines also convey wind direction - with a low pressure system in the southern hemisphere the system will rotate clockwise. High pressure systems rotate anti-clockwise. Marinweather.co.nz utilises complex pressure and wind modeled data to compute swell heights and winds speeds and chosen points.

What is a groundswell?
Groundswell is what all surfers live for, and what boaties need to keep a watch out for. Storms thousands of miles from the New Zealand coastline can create powerful swells which travel for days before reaching the shoreline. These swells can be generated so far away they are outside the local weather pattern. Offshore winds and blue skies can be present when a large groundswell arrives from miles away.

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