(a) Abdullah bin Shaqiq al-Uqayli says that a man said to Ibn Abbas (may Allah be pleased with them both): The prayer! He remained silent. He said again: The prayer! He again remained silent. He said again: The prayer! He again remained silent. Then he said: May you have no mother! Are you teaching us about prayer? We used to combine these two prayers in the time of the Prophet (peace and blessings be upon him).
(b) In both narrations of Ibn Abbas (may Allah be pleased with them both) there is no negation of rain or of travel; rather, both are to be understood as referring to one of the two.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 5554