Individual cirrus cloud formations can be the remnants of anvil clouds formed by thunderstorms.

单独的卷云的形成可以通过雷暴砧状云形成的残余。

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Moreover, the dense positive CG flashes can also be observed in the strong echo region, while sparse ones are in the weak and stable echo region or cloud anvil in the rear MCS.

密集的正地闪也与强回波区相对应，而稀疏的正地闪则多发生在系统后部的稳定性降水或云砧部位。

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It's a huge towering dark cloud, shaped at the top like a blacksmith's anvil, and responsible for sudden downpours.

BBC: Weather talk: Is there a way to make it interesting?