Protest loudly at the weather (7)

I believe the answer is:

thunder

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'weather' is the definition.
(thunder is a type of weather)

I cannot understand how the rest of the clue works.

(Other definitions for thunder that I've seen before include "Booming noise after lightning" , "What comes with lightning" , "Booming noise from the heavens" , "Heavenly claps?" , "Reverberate" .)

I've seen this clue in The Daily Express.

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