When AAabdullah Ibn Az-Zubayr used to hear thunder he would stop talking and say:
Chapter
Supplication upon hearing thunder
2 entries
سُبْـحانَ الّذي يُسَبِّـحُ الـرَّعْدُ بِحَمْـدِهِ، وَالملائِكـةُ مِنْ خيـفَته.
Subhanal-lathee yusabbihur-raAAdu bihamdih, walmala-ikatu min kheefatih.
Translation
How perfect He is, (The One) Whom the thunder declares His perfection with His praise, as do the angles out of fear of Him.