Hello semsaudade,
when facing problems in translation, it's a good idea to start with a sentence which is simple enough for you to translate.
Following this scheme, let's begin with "It rains". This sentence means that rain comes down from time to time. The Russian sentence "Идёт дождь" means literally "Rain is going" and may be translated as "It is raining". So, "Идёт дождь" implies it's raining
now. To make this sentence mean "it rains
from time to time" we can just add the word "иногда". After that the sentence appears as "Иногда идёт дождь". Note that you may not just say "Ходит дождь" to mean "It rains sometimes", because there is no such expression in the Russian language.
Analogously, one may translate "It doesn't rain" as "В наши дни дождь не идёт". The expression "в наши дни" means "nowadays" and makes the Russian sentence refer to some time period containing the present moment. Without this expression the sentence would refer only to the present moment and therefore would mean "It is not raining".
Taking into account the discussion above, we come to the conclusion that we may translate "It doesn't rain anymore" as "В наши дни дождь больше не идёт". The meaning of this sentence is pretty strange because you can hardly find an area where rain doesn't come down nowadays (if you're talking about Earth
). You might've meant "It is not raining anymore", which means the rain is over.
As for the sentence "It is raining again", one may translate it as "Снова идёт дождь".