Yes, it is permissible to combine `Asr with Zuhr and shorten them in your home city if you are traveling. The ruling allows for this convenience in order to ease the burden of prayer while on a journey. It is recommended to perform the combined and shortened prayer as soon as the time for Zuhr begins. However, if you are able to pray each prayer separately within their respective times, it is better to do so. PapaSurvey