Tam Valley MegaTree. The Tam Valley MegaTree is up and running 5-10pm every night. The MegaTree is a 30 foot tall tree of 3000 individually controlled lights that dance to holiday music. You can safely enjoy the tree from your car by tuning into 96.1 FM. We are up and running 5-10 pm nightly with 8 different shows. 340 Jean Street, just off Shoreline 1/2 mile west of Tam Junction, Mill Valley.