Atlantic swell, and why it cancels trips in fine weather
This is the cancellation that annoys people most, because they look at the sea from the promenade, see it flat and cannot make sense of it. Swell is invisible from the shore and has nothing to do with that day’s wind: it comes from a storm that may be a thousand kilometres away.
What swell actually is
A distant low in the North Atlantic generates waves. Those waves travel thousands of kilometres without the wind needing to keep pushing them, and reach the Canaries as long-period waves: little apparent height, a long distance between crests, and enormous energy behind them.
From land the sea looks calm because there are no whitecaps and no wind. What there is instead is a slow, deep movement that becomes a serious problem in the mouth of a small harbour.
Why the west coast is hit hardest
Los Gigantes lies on Tenerife’s west coast, facing the open Atlantic, and its harbour is small and wedged under the cliffs. With long-period swell coming straight in, manoeuvring in the harbour mouth is the first thing that becomes unsafe — long before the sea looks rough.
So the decision does not depend on whether it is a nice day. It depends on the direction and period of the swell, and on whether the boat can enter and leave safely.
What you can do when booking
- Leave slack. If you have only one day for that trip and the swell arrives that day, there is no plan B. Booking early in your stay leaves room to reschedule.
- Ask about the policy before you pay, not after: what happens if the operator cancels for sea conditions.
- Do not read it as an excuse. A skipper who cancels while the promenade is full of people in swimwear is making the hard call, not the easy one.
One sign you can actually see
If you look into the harbour and the water rises and falls slowly against the quay, in a long rhythm and with no wind, that is swell. The flat surface does not contradict it: they are two different things happening at once.
Frequently asked questions
›If it is sunny with no wind, why is the boat cancelled?
Because swell is not generated by local wind. It is long-period waves created by a distant low, arriving with great energy and little apparent height. In the mouth of a small harbour like Los Gigantes they make manoeuvring unsafe well before the sea looks bad.
›How do I know whether there will be swell on my day?
Not by checking the wind forecast. You need the wave forecast: the height, and above all the period. A long period with modest height is the signature of swell, and it is what decides whether a small harbour operates.
›Do I get a refund if the operator cancels?
When the operator cancels for sea conditions, the usual outcome is rescheduling or a refund. It is worth reading that specific condition on the excursion page before paying, because it is the one that applies in the only case where you have no say.