Is it permissible to combine and shorten the Dhuhr and Asr prayers in Madinah, with the intention of traveling to Yanbu, and to miss the congregational Dhuhr prayer?

The answer involves two issues:

First: You should have prayed Dhuhr in congregation in your village, because congregational prayer is obligatory for an able man who hears the call, even if he is a traveler, according to the saying of the Prophet, peace and blessings be upon him: "Whoever hears the call and does not answer it, there is no prayer for him except for an excuse."

Second: It is not permissible for a traveler to shorten and combine prayers except after leaving the inhabited houses of his town. Your prayer of Dhuhr and Asr combined and shortened at a station that is still part of the village is considered before passing the inhabited area, which makes the two prayers incomplete, and they must be made up fully with four rak'ahs for each prayer.