You may need to create a variable that has the value of tomorrow's date as a string. Here's one way you can achieve this using some Python scripting in a Transform node.
The ConfigureFields script imports the required Python timedelta modue and defines the output metadata:
The ProcessRecords script is configured to retrieve the date when the data flow is run and create a datetime variable (TodayDT) with that date. It then creates a 'timedelta' object that has a duration of one day. The script then calculates the datetime value for tomorrow. It then outputs a datetime field containing tomorrow's date, a date type field with the same date and finally, a string field containing the formatted date (in this case the format pattern is set to not include any delimiter characters so that it could, for instance, be used as part of a file name):
See the attached data flow (requires Analyze 3.6.x)