Following examples shows how to display a future date and time.
$ date Thu Jan 1 08:30:07 PST 2009 $ date --date='3 seconds' Thu Jan 1 08:30:12 PST 2009 $ date --date='4 hours' Thu Jan 1 12:30:17 PST 2009 $ date --date='tomorrow' Fri Jan 2 08:30:25 PST 2009 $ date --date="1 day" Fri Jan 2 08:30:31 PST 2009 $ date --date="1 days" Fri Jan 2 08:30:38 PST 2009 $ date --date="2 days" Sat Jan 3 08:30:43 PST 2009 $ date --date='1 month' Sun Feb 1 08:30:48 PST 2009 $ date --date='1 week' Thu Jan 8 08:30:53 PST 2009 $ date --date="2 months" Sun Mar 1 08:30:58 PST 2009 $ date --date="2 years" Sat Jan 1 08:31:03 PST 2011 $ date --date="next day" Fri Jan 2 08:31:10 PST 2009 $ date --date="-1 days ago" Fri Jan 2 08:31:15 PST 2009 $ date --date="this Wednesday" Wed Jan 7 00:00:00 PST 2009