Source: Tafsir al-Ahlam al-Kabir (Ibn Sirin)
Thunder in a dream is a threat and a warning from the ruler. It may also indicate the king's commands. Thunder alone indicates fear and strife. If it is with rain, it indicates goodness and sustenance.
Source: Ta'tir al-Anam fi Ta'bir al-Manam (Al-Nabulsi)
Thunder indicates fear of the ruler, and it may indicate praising and thanking God. Hearing it indicates strife, wars, and disputes.
Source: Al-Isharat fi Ilm al-Ibarat (Ibn Shahin)
Thunder is interpreted as fear of the ruler. If it is with rain and lightning, it is great goodness and benefit. Hearing thunder in its season indicates glad tidings of goodness.