To find out what cruise ships are in Southampton today, we can check the Southampton VTS Cruise Ship Schedule. However, the schedule only lists ships that are due to arrive or depart within the next six days, so it may not be up-to-date for today. Another source of information is CruiseDig, which lists the schedule for the next few days. However, it is also possible that some ships are not listed on either of these sources. Therefore, the most reliable way to find out what cruise ships are in Southampton today is to check with the Port of Southampton directly.