What is swell period and why does it matter? 

To mark Safer Boating Week, we thought we'd dive in and help boaties work out what sea conditions to expect when they see both sea state and swell mentioned in our coastal and recreational marine forecasts. To get you in the mood, let's talk about various states of discomfort that can be found on a boat. 

Besides the coastal waters, the MetService forecasting team produces marine forecasts for a number of smaller areas where there is a lot of recreational boating activity. These forecasts are routinely issued four times every day; they are monitored continually and updated more frequently if conditions warrant it.

Recreational Forecasts

MetService's forecasting team produces marine forecasts for New Zealand coastal waters. These forecasts are routinely issued four times every day; they are monitored continually and updated more frequently if conditions warrant it.

Coastal Forecasts

Forecasts for coastal waters cover the area from the coastline to 60 nautical miles (about 100km) out to sea. The New Zealand coast is divided into 18 areas, as shown in figure 1: