GOING TO FUTURE:
The going to future (to be (am, is, are) + going to + infinitive) is used to indicate:
1.- Planned actions in the future:
a) I am going to visit my grandparents.
b) We are going to sing at the party
2.- A prediction based in present evidence:
a) Look at those dark clouds! It is going to rain.
b) Watch out! You are going to fall!