Tenerife is one of the (Spanish) Canary Islands, a group of volcanic islands off the coast of Africa about 400 miles SE of Casablanca, Morocco.  Their location guarantees luscious cloud cover and their volcanic nature provides peaks that rise above those clouds, as you can see here.

High peaks provide ideal locations for weather stations and antennas such as are seen in this image.  It's ideal for other things, too.  See that reddish blob above the ridgeline near the weather station?  Click it.

Parasailers launch from near the antennas for Tenerife's radio and TV services.  The highest spot on Tenerife is the peak of El Teide at about 12,000 MSL, but these daredevils are only jumping from about 7500 MSL. 

Even so, they're launching above the cloud layer, and their destination is below the cloud layer down near the beach, so they'll lose all of that 7,500 feet before putting their boots on the ground.

Because they're going to pass through the entire cloud layer, they're going to be very wet by the time they reach the ground.  Clouds, in case you haven't yet figured it out, are just 'high fog' (or fog is 'very low clouds'), so they're navigating through several hundred feet of dense London fog on the way.  It will be like riding a motorcycle in the rain.