The sky was bright orange across much of the UK on 16 October 2017 © Rob Ball/Getty

Why does the sky change colour on the brink of a hurricane?

The orange sky does not mean it is the end of days...

It seems like 2017 is the year of the hurricane, with America and the Caribbean suffering a particularly harsh battering. One hurricane, Hurricane Ophelia, ventured so far as Ireland and, although the devastating storm did not stretch to England and Wales, residents did observe a rather peculiar spectacle. Skies cast an eerie yellow glow across the UK while the Sun shone a vivid orange, comparable to sunset or sunrise, but instead glowing throughout the day. People were quick to notice this unusual phenomenon and question what was happening, so we caught up with Met Office Forecaster, Helen Chivers, to uncover the answer:


“You may recently have sensed a distinct rise in temperatures, uncharacteristic of mid-October; this was due to Southerly winds from Africa, Spain and Portugal extending up to British shores which preceded Hurricane Ophelia. As the hurricane whirled past Africa, she collected dust particles from the Sahara Desert, and as she continued up past Western Europe, Ophelia accumulated smoke from the wildfires of Northern Iberia. The bundle of dust and smoke particles were lifted high into the atmosphere where they split out the light spectrum. Blue light, which usually paints the sky, was scattered enabling more yellow and orange light to break through. The abundance of mainly yellow and orange light resulted in the yellow-tinged sky and striking orange Sun.”

All this dust and smoke in the air doesn’t sound desirable for the creatures breathing beneath it, humans included, however Helen reassures us that the particles were elevated too high into the atmosphere to elicit any adverse health effects, so we were free to enjoy the remarkable natural phenomenon while taking no personal risk.


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