Below, from the White House....
Preliminary August Vacation Details
On Saturday, August 14th, the First Family will travel to Florida's Gulf Coast, where they will spend the weekend. Both the President and Mrs. Obama have travelled to Florida's gulf coast in recent weeks and they look forward to returning for the weekend.
On the 19th, the Obama family will travel to Martha's Vineyard. After a busy and productive July, they are looking forward to returning to Martha's Vineyard to spend time together as a family before heading back to Washington on the 29th.
Additional details will be available at a later date.