DANA, mistral, bora and calima: the weather phenomena of your holiday explained

Anyone who delves into the weather of Southern Europe soon encounters a handful of local names. They sound exotic, but they often determine whether a day remains calm or suddenly becomes dangerous. Here are the main phenomena from our travel guides, explained straightforwardly.

DANA — the autumn downpour of Spain's east coast

A DANA is an isolated pocket of cold upper-level air above the warm waters of the Mediterranean Sea that leads to enormous rainfall.

In October 2024, a DANA around Valencia caused flash floods with more than 220 deaths.

• Where: mainly Spain's east coast — Costa Blanca, Valencia region.
• When: autumn (September–November), when the sea is at its warmest.
• Why it matters: dry riverbeds (barranco's) fill up in minutes. Don't book in or near them.

Mistral — the dry föhn wind of southern France

The mistral is a strong, dry, cold northerly wind that races through the Rhône valley towards the Mediterranean Sea.

• Where: Provence, the Rhône region, and (as a comparable wind) Corsica.
• Why it matters: the mistral dries out vegetation and fuels wildfires. During mistral conditions, fire risk increases sharply.

Bora — the föhn wind of the Adriatic coast

The bora is a cold, dry föhn wind that plunges from the mountains towards the Croatian coast, sometimes in severe gusts.

• Where: the Dalmatian coast and Croatian islands.
• Why it matters: like the mistral, the bora can cause a coastal fire to spread rapidly. Warnings during bora conditions are no formality.

Calima — the Saharan dust of the Canary Islands

Calima is a period when dust and sand from the Sahara blow across the Canary Islands.

• Where: the Canary Islands.
• When: mainly winter and spring.
• Why it matters: the air becomes hazy and air quality drops. Usually merely inconvenient, but unpleasant for sensitive airways. Typically clears within a few days.

Cévenol downpours and supercells

Two phenomena associated with heavy summer and autumn weather:

• Cévenol downpours: short, extremely intense rainfall in the hinterland of southern France (Languedoc, Cévennes), especially in September and October.
• Supercells: the most powerful type of thunderstorm, with large hail. The Po Valley and the edge of the Alps (around Lake Garda) are among Europe's most active areas.

In brief

DANA, mistral, bora, calima, cévenol and supercells are not trivia for weather enthusiasts — they determine when and where risk peaks. Recognise them, and you'll better understand the warnings and plan more wisely. Check the current forecast for your destination shortly before departure.