Answered by Shaykh Faraz Rabbani
an imam at a local masjid advised me that if i perform salaah in the rain then my namaaz is invalid. i also had another friend who suggested that rainwater is pure and therefore does not invalidate namaaz. if rainwater does invalidate namaaz then will it also make your clothes impure if left to dry outside and they get wet in rain.
المياه التي يجوز التطهير بها سبعة مياه 1- ماء السماء
نور الإيضاح
Seest thou not that Allah sends down rain from the sky, and leads it through springs in the earth?
أَلَمْ تَرَى أَنَّ اللَّهَ أَنْزَلَ مِنْ السَّمَاءِ مَاءً فَسَلَكَهُ يَنَابِيعَ فِي الأَرْضِ ….. (21) سورة الزمر
and he caused rain to descend on you from heaven, to clean you therewith, to remove from you the stain of Satan, to strengthen your hearts, and to plant your feet firmly therewith.
وَيُنَزِّلُ عَلَيْكُمْ مِنَ السَّمَاءِ مَاءً لِيُطَهِّرَكُمْ بِهِ وَيُذْهِبَ عَنْكُمْ رِجْزَ الشَّيْطَانِ وَلِيَرْبِطَ عَلَى قُلُوبِكُمْ وَيُثَبِّتَ بِهِ الْأَقْدَامَ (11) سورة الأنفال
and We send down pure water from the sky,-
وَهُوَ الَّذِي أَرْسَلَ الرِّيَاحَ بُشْراً بَيْنَ يَدَيْ رَحْمَتِهِ وَأَنزَلْنَا مِنَ السَّمَاءِ مَاءً طَهُوراً (48) سورة الفرقان