The shower cloud with dark, ragged base and heavy, localized rain, hail, or other severe weather.

这种阵雨云的底部阴暗不规则，常带来大型降雨，局部降雨，冰雹或者其他恶劣的天气状况。

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Businesses are tired of hearing the tech industry squawk about whether this or that is a managed service or a faux cloud or a virtualized cumulonimbus cluster or a passing shower or black cloud of doom.

FORBES: The New and Dangerous Threat to Cloud Computing