How can we reconcile free will with God's omniscience?
The short answer
There is nothing to reconcile. Knowing the sun will rise tomorrow doesn't make you cause it. God knows our future free choices, but they remain ours and remain free.
Knowing isn't causing
Knowing the sun will be in the sky tomorrow doesn't mean you cause it to be there.
Still free
God already knows what we will freely choose, yet our choices are still ours and still free. If our choices change the future, God has known that from all eternity.