What changes for visitors on Wednesday?

The yellow warning covers all seven islands from 11:00 to 19:59, according to AEMET, the state weather service. If you have excursions or beach days planned, work around that window.

A beach morning is more likely to work than an afternoon. AEMET says the showers will be scattered but can turn heavy in places, though it cannot predict exactly where.

AEMET stresses the uncertainty over where, how hard and how long it will rain. So decide at short notice, and check AEMET's latest update before you set off.

Hikes and mountain drives are the riskier choice that day, because the rain will hit the interior of the islands hardest, AEMET says. A stroll along the seafront is the safer bet.

Where exactly does the warning apply?

The south of Gran Canaria and Tenerife, home to many holiday resorts, is explicitly included. No breakdown for individual resorts is available.

On Lanzarote, Fuerteventura, La Gomera and El Hierro, the warning covers the whole island. On Gran Canaria, it covers the north, east, south and west, plus the summit area.

On Tenerife, it also covers the north, east, south and west, along with the metropolitan zone. On La Palma, it applies to the summits and to the east and west of the island.

What do yellow and the pre-alert level mean?

Yellow is the lowest level on AEMET's colour scale of yellow, orange and red. It signals a low risk, but vulnerable people and exposed property can be affected, so stay informed.

The Canary Islands government runs its own pre-alert level, which its emergencies directorate-general triggered. It builds on the PEFMA emergency plan and on figures from AEMET.

The government points to “uncertainty” over where, how hard and how long it will rain. It is monitoring the situation continuously.

What is known about damage and consequences?

The rain had already caused more than 20 incidents across the islands in the early hours. No breakdown by island or type was available.

Whether anyone was injured or anything was damaged is not known. The information available did not confirm any closures, cancellations, flight disruption or road closures.

Snow cannot be ruled out on the summit of Tenerife. The altitude, and whether roads or the cable car can be reached, were not confirmed.

How should you behave in a storm and heavy rain?

In such conditions, the authorities advise avoiding unnecessary journeys, especially on minor roads. Never cross a swollen barranco (ravine), and stay off mountain paths.

Keep away from breakwaters, piers and stretches of coast where waves are breaking. In an emergency, call 112.

What happens after 19:59 is open. It is not confirmed whether AEMET will extend the warning or raise it to orange, so check aemet.es.