Bismillahi Al-Rahmani Al-Rahim
If [someone] lives in a country like the USA or UK where it is not easy to
find someone truly in need of Zakah money and is going travel to a
country where there are a lot of very poor Muslims who can use the
money, can such a person give their Zakah in advance?
[message edited --musa]
It is permissible, but not recommended, to pay zakah up to two years in advanced. Zakah is distributed to qualified recipients in the area where the wealth which necessitated the zakah is located. If there are no qualified recipients then it can be given to the next closest land, and then the next closest, and so on.
The basis for answers to your questions comes from the following passages from Zad al-Mustaqni`:
It is best to extract all of the zakh for the poor of his land. It is not permissible to transport it to [a location] where prayer would be shortened [if one traveled to it]-and if one does so it suffices-unless there are no poor in the land, and in that case he distributes it in the land closest to him.
If he is in one land and his property in another, the zakh on property is extracted in the land where the property is located, and his Fitra (b: is extracted) in the land where he is located.
It is permissible to pay Zakh for up to two years in advanced (b: and it suffices as zakh if the person it was given to died or ceased being poor before the end of the year, but not if it was given to someone who was not poor and then became poor during the year), but it is not recommended. (Zad al-Mustaqni` [e5.2])
But in light of electronic banking, you'll have to ask someone else where you money exists.
And Allah knows best.
Wa al-salamu `alaykum,