Firstly, remember that question forms require an inversion of subject and object. So you could ask either 'Is it possible that you will ...?' (or 'you'll) or 'Is it possible that you would...?' (or you'd) You could ask either of these questions. The difference is that the second is more tentative or hypothetical. Secondly, it is important to understand that ALL references to the future in English are based on a degree of certainty or likelihood. There is no future tense as such in English grammar - only modal verbs (will, would, may, might, could) , which suggest varying degrees of certainty. This means that it isn't even necessary to say 'Is it possible that....?' . The modal verbs which we use to express likelihood in the future include the concept of 'Is it possible that...?'. A more natural question might be, for example: 'Do you think that you might....?' 'Is there a chance that you might..?

I think really you would have to use the present simple because you are not sure that will happen.