Even for a region sadly accustomed to monster fires, the out-of-control wildfires raging in Los Angeles are proving shocking. More than 180,000 residents have been instructed to evacuate their homes, while at least five major blazes have ravaged thousands of hectares near the heart of the US's second-largest city, and are progressing apace. The flames, which led to scenes of chaos, killed five people and burned at least 2,000 homes and buildings, including those of Hollywood movie stars. With the destruction of around 100 luxury homes, the fire is said to be the most costly ever recorded in California.

But the exceptional nature of the fires lies above all in their seasonality, in the middle of winter, a rare phenomenon in California. All the ingredients were in place for these "unprecedented fires in Los Angeles," in the words of California's governor, Democrat Gavin Newsom.

The first culprits are the Santa Ana winds. Typical of Californian autumns and winters, they blow down from the mountains, pick up speed, then reach the coast, bringing warm, dry air. But this week they reached an intensity not seen since 2011, according to meteorologists, "hurricane force," said Los Angeles Mayor Karen Bass. Gusts reached 160 kilometers per hour on Wednesday, January 8, sometimes carrying embers for miles.

You have 74.53% of this article left to read. The rest is for subscribers only.