Praise be to Allah the Lord of the Worlds.
Combining prayers because of strong wind and mud is a matter of disagreement amongst scholars, because this exemption is granted in case of rain. Therefore, Maliki and Hanbali scholars have included other factors causing hardship similar to rain. As for the Shafi scholars, they have limited this exemption to rain, because their methodology rests on avoiding expansion in exemptions.
However, Hanafi scholars don`t permit combining prayers under any condition. The view of both Maliki and Shafi schools of thought-permissibility of joining prayers for a reason other than rain-is limited to Maghrib and Ishaa` prayers. They have also added other conditions to mud and strong wind in order for the combining to become permissible. In one saying, the Hanbalis permitted combining prayers because of strong wind and darkness.
Thus, there should be wind, darkness and cold, but if there is only wind or only cold then the combining isn`t permissible. Ibn Qhod-damah says in {Al-Moghni, 2/302}, "As for the strong wind on the dark cold night, there are two views: First: It is permissible to combine prayers. Al-Amidi stated, this is the more correct opinion, and it is that of Omar Bin AbdulAziz, because strong wind, cold weather, and darkness are also valid excuses for not going to Friday and congregational prayers. Second: It isn`t permissible, because hardship caused by mud, wind and cold is lighter than that caused by rain. Therefore, it is wrong, here, to take rain as a point of analogy. Maliki scholars said that there should be both mud and darkness in order for combining Maghrib and Isha` to become permissible."
It is stated in {Mokhtasar Khaleel, p. 44}, "In every mosque, it is permissible to combine only Maghrib and Isha` in case there is rain or mud and darkness. No matter what the case may be, combining prayers, because of rain or strong wind and coldness, is an exemption granted to whoever faces difficulty going to the mosque under such weather conditions."
We recommend that prayer performers follow the Imam`s decision in this regard since he is the one who will be held liable for the validity of their prayer. If the Imam decides not to combine prayers and the praying person is harmed by coming to the mosque, then the latter is allowed to pray at home. He could also bear the hardship of coming to the mosque to receive the reward of the congregation.
The permissibility of praying at home in case of heavy rain and difficulty to get to the mosque is indicated by many authentic narrations. For example, Jabir reported: "We set out with the Messenger of Allah (PBUH) on a journey when it began to rain. Upon this he said: He who desires may pray in his dwelling."{Muslim}. Kindly refer to An-Nawawi`s {Shareh An-Nawawi Ala-Muslim, 5/207}.
As for combining prayers because of dust, scholars haven`t permitted that, because it rarely happens. And Allah the Almighty knows best.
