Top: rain 雨 (= window 冂 with cloud 一 and drops 丶丶), below: field 田 [cf. Electricity 电: When lightning strikes the field 田, then the lightning rod 乚 has electricity]
Mnemonic
Rain falls on the field amidst thunder. [Or: The rain 雨 on the field 田 without lightning 乚 has only a thunder.]
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