Present Continuous Tense
As you know Present Continuous Tense is used to describe ac action in progress as the moment of speaking or around the the time of speaking, this tense is also used for the action in the near future; the action that some one has arranged to do something in the future.
Some of you might have no idea whether it means the present or the future, so look at the samples to notice the sentence pattern in green and the phrases of time in orange.
Moreover, we also use "be going to" for the planned action in the future.
Eastwood, J. (1999). Oxford Practice Grammar with Answers (2nd ed.) Oxford: Oxford.
Foley, M. & Hall, D. (2003). Longman Advanced Learners' Grammar. Essex: Pearson.