The lightning requires rain
1
جَعْفَرُ بْنُ بَشِيرٍ عَنْ رُزَيْقٍ عَنْ أَبِي عَبْدِ اللَّهِ (عليه السلام) قَالَ مَا أَبْرَقَتْ قَطُّ فِي ظُلْمَةِ لَيْلٍ وَ لَا ضَوْءِ نَهَارٍ إِلَّا وَ هِيَ مَاطِرَةٌ.
267. Ja’far Bin Basheer, from Ruzeyq, who has reported the following: Abu Abdullah (asws) has said: ‘Lightning does not occur at all in the darkness of the night or the light of the day unless it is raining’.