Tenerife and the Canary Islands are well known and popular with holiday-makers because of the wonderful weather to be found there with plenty of sunshine more or less guaranteed but occasionally a strange weather phenomenon known as “calima” affects the islands bringing extremely hot temperatures and lowered visibility from air-borne dust.

Calimas are caused by dust storms that have been stirred up by high winds in the Sahara desert and are then blown over to the Canary Islands by southeasterly winds.

The very fine sand and dust particles cause the air to become difficult to see through for any distance thick and the appearance and visibility is like what you get during a thick fog. The difference being that in fog it is cool and damp but in a calima it is hot and dry.

During the time a calima is over the island, every surface will get covered in fine reddish brown dust, which is a great annoyance to car-owners and people who are house-proud. The dust can also seriously affect the health of people with breathing conditions like asthma and bronchitis.

Many people find the temperatures unbearable too and whilst the warm weather is an attraction of the Canary Islands, the sort of heat generated by a calima can prove to be very unpleasant, especially if the phenomenon lasts for days.

It can be very strange to experience very low visibility at midday and in the afternoon when you know the sun is shining brightly and the heat is extreme and yet everywhere you look it is like trying to see through a dense fog.

The dust clouds can be some massive in size that satellite pictures of the Canary Islands will show them clearly. Fortunately normal weather returns as soon as the calimas blow over.

I went to the resorts of Los Cristianos and Playa de ls Américas once in a calima and got some very unusual photos as you can see here. The ships and boats on the sea looked like ghost ships and some surfers and bathers looked more like something out of a horror movie. I came up with the title Zombie Surfers From Hell!

Sometimes locusts are also blown over from the Sahara region of North Africa but they usually don't live long after their journey, which is probably just as well for the farmers and gardeners of the islands. I was nevertheless fascinated when I first came to Tenerife to see locusts in the streets of La Laguna where I was staying.

The dust from calimas that originate in the Sahara can be carried across the Atlantic Ocean much further than the Canary Islands and can reach as far as Florida and Puerto Rico. 

The Calima or The Temple of Semos, is also a forbidden but holy site for the apes in Planet of the Apes, and as a matter of interest some scenes for the movie were shot on location on Tenerife’s Mt Teide, which is the highest mountain in Spain.

Wikipedia explains:

"Calima turns out to be the remains of the Oberon, his former space station, which has crashed on the planet's surface and looks ancient (the name Calima coming from the sign "CAution LIve aniMAls", the letters Calima being those not covered in dust)."

Calima is not to be confused with the Hindu Goddess Kali Ma.