A column of smoke from wildfires in California descended on the San Francisco area, causing the sky over the area to turn orange.
Around 14,000 firefighters are fighting 28 major blazes across California amid a historic heatwave.
Forest fires have burned more than 2.5 million acres in the state this year, killing at least eight people.
On Wednesday, strong winds blew smoke and ash from some of those fires in northern parts of the state.
Residents of San Francisco and surrounding areas woke up to a dark sky, which confused some, who thought it was still night.
Catherine Geslin, who lives in the West Portal area of the city, “looks like the end of the world.” Tell the San Francisco Chronicle.
“It was disturbing to see the darkness still dark. It would be strange to have lunch in the dark. But you still have to carry on with your day.”
Local media reported It still appeared to be at dawn at 10:45 (18:45 GMT), as the sun’s rays struggled to penetrate the thick smoke.
In a tweet, Daniel Swain, a climate scientist at the University of California, Los Angeles (UCLA), said that the “tall plumes of smoke” are “very dense” and “almost completely block out the sun’s rays.”
Experts said that this smoke was also behind the sky-orange glow.
Smoke particles from forest fires “only allow yellow-orange and red light to reach the surface, making the sky appear orange”, The Gulf Air Quality Management region explained on Twitter.
“This is not a familiar sight because this requires very specific conditions for this to happen.” Brian Garcia, the National Weather Service (NWS) forecaster told SFGate. “Obviously, you need thick smoke fires.”
As wildfires continue to rage, forecasters expect similar conditions in the coming days.
More on California wildfires
- Hikers rescued by helicopter as California fires rage
- Gender revealed a party blamed for California wildfires
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