lightning, thunder
霆 centers on a sudden, violent atmospheric discharge: lightning and the thunder that accompanies it. The two meanings are two aspects of the same electrical storm phenomenon.
霆 combines 雨 (rain) with 廷, which likely provides the sound. The character expresses the idea of a sudden, loud atmospheric event—lightning or thunder—associated with rain.
Rain 雨 pours down from the top, and below it 廷 looks like a courtyard struck by a sudden bolt. Picture a lightning strike hitting a palace courtyard during a storm: 霆 is lightning and thunder.
For テイ, imagine a lightning bolt hitting a metal T-shaped antenna on a roof: T -> テイ, and the thunder roars.