Pockets of vegetation and debris continue to burn within the perimeter of the Microwave Tower Fire, continuing to produce smoke that may be visible from Interstate 84.  Containment remains at 89%, with the size at 1,313 acres.  Rising temperatures coupled with low relative humidity may contribute to a slight increase in fire activity within its interior.  Along the steep northern section, as vegetation burns it can break loose, roll downhill, and ignite additional material.  Crews are monitoring and extinguishing hot spots where accessible by hand or utilizing a system of hose lays and sprinklers.  The Historic Columbia River Highway State Trail remains closed.