Sean Farrow writes:

Can the boost date class be constructed with a time, or do I need a separate time variable as well? If so, should I use a local time, or posix time, given that the time has already been converted from utc to the users timezone.

boost::gregorian::date does not have "time" component in it. However boost::posix::time and local_date_time do have "date" member - may be it is what you are looking for? Depending on what time type (posix or local) you are using you might get a shift in the date due to UTC.