The thunderstorm moves away, the downpour eases, and suddenly everything is bathed in rich yellow light: buildings, trees and the wet tarmac seem to glow from within. Ten minutes later, the colour fades, and the sky goes back to normal. We explain where this "golden" sky comes from, and why it appears specifically after rain.
In September 2026, residents of Ho Chi Minh City in Vietnam filmed an orange sky en masse on their phones: after an evening thunderstorm the clouds parted, and within minutes the western part of the sky blazed bright orange.
"At around 6pm I went out onto the balcony and saw the whole western sky light up bright orange," one local resident said.
Similar footage appears in Russian cities too: in summer 2023, for example, after an overnight downpour, the dawn over Yekaterinburg painted the sky pink and gold. But what's behind it?
Why the Sky Is Blue During the Day
To understand why the sky turns yellow, we first need to look at its usual colour. Sunlight is a mixture of all the colours of the rainbow. As it passes through the atmosphere, it collides with air molecules, which scatter blue and violet light much more strongly than yellow, orange and red. This phenomenon is called Rayleigh scattering.
Scattered blue light reaches us from all parts of the sky, so during the day the sky looks blue. And the sun's disc itself looks slightly yellowish: some of the blue light has already been "taken out" of its direct rays.
What Changes in the Evening
When the sun sinks towards the horizon, its rays have to travel through a much longer stretch of atmosphere. Along the way they lose almost all their blue light, and what reaches us is mostly yellow, orange and red.
"You could say that sunsets are red because the daytime sky is blue," says Stephen Corfidi, a meteorologist at the US National Weather Service's Storm Prediction Center.
Usually, these warm colours are visible only near the horizon and on the clouds. But after rain, a special situation arises in which the whole sky is flooded with yellow light.
Why Specifically After Rain
Three factors are at work here.
- Clean air
Rain washes dust, smoke and other particles out of the atmosphere. "When thunderstorms bring a lot of rain, they clean the air of pollution," explains Samara Cokinos, a meteorologist at the Florida TV channel News 6. Dust and smog usually make sunset colours pale, while in clean air they come out rich and bright.
- Humidity
After rain, the air is left full of tiny water droplets. Unlike air molecules, these scatter light of all colours almost equally. So the sunset light, already tinted yellow, doesn't just travel in one direction but is scattered in all directions, lighting up the whole sky rather than just the horizon.
- Clouds as a screen
The departing storm cloud acts as a giant reflector. The low sun shines under its bottom edge, and the clouds reflect the yellow-orange light back down to the ground. If there's a lot of cloud, the whole landscape is bathed in warm light.
Why It Happens in the Evening and in Summer
In our latitudes, weather most often moves from west to east. So an evening thunderstorm usually moves away to the east, while in the west, where the sun is setting, the sky clears.
The result is the ideal set-up: the sun is low, shining from beneath the edge of the departing cloud, and the air is clean and damp.
This happens especially often in summer, when thunderstorms come in the evening after the day's heating. The phenomenon doesn't last long, usually 10–15 minutes, until the sun sinks too low or clouds close the gap.
What if the Sky Is Yellow Before a Storm?
A yellow, and sometimes greenish, sky can also be seen before a thunderstorm. In this case, the light passes through a huge thickness of cloud full of water and ice, which holds back some colours and lets others through. American forecasters stress that this is not a sign of a tornado.
Mike Fowle of the US National Weather Service office in Des Moines warns that you can't predict a tornado from the colour of the sky, as too many other factors are involved. But that's no reason to relax: a sky like this signals a powerful thunderstorm cloud, so a downpour, hail or a squall are quite possible.
When a Yellow Sky Has Nothing to Do With Rain
Sometimes the sky turns yellow without any rain at all. The cause is dust or smoke high in the atmosphere. In October 2017, for example, the sky over the UK turned yellow and the sun orange. Hurricane Ophelia had brought in dust from the Sahara and smoke from wildfires on the Iberian Peninsula.
"The abundance of mainly yellow and orange light made the sky look yellow and the sun look bright orange," explained Helen Chivers, a forecaster at the UK Met Office.
Smoke from large wildfires and dust storms have a similar effect. It's easy to tell a sky like this from the "after-storm" kind: it lasts for hours or days rather than a few minutes, and usually comes with a smell of burning or a dusty haze.
How to Catch a Yellow Sky
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Watch for evening thunderstorms. Your best chances are when a downpour passes an hour or an hour and a half before sunset, and the forecast promises clearing skies from the west.
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Look west, but glance behind you. The brightest colours are in the western part of the sky, but sometimes the departing cloud in the east is lit up yellow too, and a rainbow may appear against it.
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Don't hang about. The phenomenon lasts only a few minutes, so if you see everything around you turn yellow, get out onto the balcony or to a window straight away.
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Shoot without filters. Phone cameras often "even out" warm tones automatically. To get a photo that shows the real colour, switch off automatic white balance or choose the "daylight" setting.
