Thursday, July 22, 2010

Marine forecast

Sun is not in the forecast

We listened intently on the morning we were hoping to get our paddle underway in Harbour le Cou. The marine forecast has to be short and concise, therefore its important to listen carefully and know what information the service provides.

The first bit of information given is the "marine synopsis". It gives the broad weather picture and where the major weather systems are and are moving. The mariner must keep this in mind when interpreting the forecast for the local marine area.

The actual weather is given only if it is expected to reduce visibility. Don't expect to hear if the sun will be splitting the rocks. No weather announcement in this case is good news. Rain and fog forecasts will be given as they affect visibility.

Wind is given in knots and only on 8 points of the compass.

Sea state is given but only for deep water defined as 50 metres or deeper. Knowing the local sub-sea topography is important in evaluating this bit of info. A 1 or 2 metre wave in deep water will kick up considerably in shallow water once it arrives. Curiously, the direction of swell isn't given.

Small craft warning are given when winds are forecast to be 20 - 33 knots or higher.

That's what we get from the Canadian service. I don't know if there are universal conventions for distribution of marine forecasts but best to know exactly what is provided locally before getting on the water.

No comments:

Post a Comment