IslaBuWhy is the north of the Canary Islands cloudy and the south sunny?
The trade winds are the reason. Moist wind from the north-east runs into the mountains, forms cloud on the windward northern side, and the south, in the lee, stays dry and sunny.
Trade winds and the sea of clouds
In the Canary Islands the trade winds (alisios in Spanish) blow from the north-east for most of the year. Moist air rises up the northern slopes of the mountains, cools and forms a layer of cloud, usually somewhere between 600 and 1,500 metres. From above it looks like the surface of a sea – it is called mar de nubes, the sea of clouds. Above it the sky is usually clear, so peaks such as Teide or Roque de los Muchachos are in the sun even when the northern coast is under cloud.
Panza de burro
In summer, low grey cloud often sits over the northern coast of the higher islands; locals call it panza de burro, the donkey's belly. It is typical of Las Palmas de Gran Canaria, for example. No rain falls from it; it just blocks the sun and keeps temperatures more pleasant.
Which islands it affects
The difference between north and south is most marked on the high islands: Tenerife, Gran Canaria, La Palma, La Gomera and El Hierro. Lanzarote and Fuerteventura are low, so the clouds do not get held up on them as much – it tends to be drier and windier across the whole island.
What to do about it in practice
When it is cloudy in the north, it is often sunny in the south, and the trip across the island is worth it. This is not always the case: with a southerly airflow or during calima the situation can be reversed. That is why IslaBu shows you every day which part of the island really has the sun.
Sources: AEMET – Agencia Estatal de Meteorología · Turismo de Islas Canarias · Updated October 4, 2026