Why did the Hong Kong typhoon happen?

* Unusually warm ocean waters: The Pacific Ocean was unusually warm during the summer of 2018, which provided the fuel for Typhoon Mangkhut. As the typhoon moved over these warm waters, it was able to rapidly intensify.

* High wind shear: Wind shear is the difference in wind speed and direction between two different layers of the atmosphere. High wind shear can disrupt the structure of a typhoon, causing it to weaken. However, in the case of Typhoon Mangkhut, the wind shear was relatively low, which allowed the typhoon to maintain its intensity.

* Rapid upper-level winds: The upper-level winds in the atmosphere were also favorable for Typhoon Mangkhut. These winds helped to push the typhoon forward, allowing it to quickly cross the Philippines Sea.

In summary, Typhoon Mangkhut was a powerful typhoon that was caused by a combination of factors, including unusually warm ocean waters, high wind shear, and rapid upper-level winds.