I don't let mine out until they get allot feathers. The brooder temp should be around 95 for 2 week old chicks so if its not about that outside I would not. You don't want them to catch a chill because they can not regulate their body temp at 2 weeks and they have no feathers for insulation.
I moved my four chicks outside at two weeks. They have lived out there for six weeks now. I turned the heat lamp off during the day and they are doing fine. They have not used the heat lamp for a little over a week.