The next megastorm is a super typhoon, set to hit Japan this weekend

Typhoon Lan off the east coast of the Philippines. Thunderstorms spiral towards the centre and the eye is obscured by high clouds. (Photo: NASA)

While the Atlantic Ocean has had one of its most active hurricane seasons on record, a huge storm is building in the Pacific Ocean off the coast of The Philippines.

Typhoon Lan formed earlier this week and is expected to turn into a “super typhoon” that will threaten the Japanese island of Okinawa.

Lan formed off the east coast of the Philippines and is expected to pass close to Okinawa on Sunday, causing strong winds, heavy rains and potential flooding. The projected forecast, which could change, has Lan continuing north-east which could potentially affect Tokyo and the Japanese mainland as a tropical storm on Monday.

Winds are predicted to reach 240kmh (150mph), making Lan a “super typhoon” – the equivalent of a category 4 or 5 hurricane. Some of the warmest waters of the Pacific Ocean are below Lan, contributing to its intensity.

(Photo: Philippine Atmospheric Geophysical and Astronomical Services Administration.)

Heavy rains in Tokyo could test the city’s flood prevention system, built after a 1991 typhoon caused heavy flooding and killed 52 people. Fifty metres underground sit huge silos ready to clear 65 million gallons (246m litres) of water, sucking in the equivalent of an Olympic pool every 12 seconds.

While typhoons are common in the western Pacific basin, only seven have come near Okinawa in the last four decades.

The eye of Lan is not predicted to make landfall at any stage.

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