Green’s Dictionary of Slang

1. to destroy, to ruin.

1952		W.R. Burnett Little Men, Big World 84: Might set off a chain of explosions that would blow the city sky high.
1981		J. Ellroy Brown’s Requiem 216: He kept telling Cathcart he would blow the whole thing sky-high if he didn’t order Solly to cut Jane loose.
1990		(con. early 1950s) J. Ellroy L.A. Confidential 57: She’d catch him in whoppers, it would blow their deal sky high.

2. to collapse, to come to ruins.

1953		L. Uris Battle Cry (1964) 234: Any co-operation [...] from the Navy will blow sky high.
1981		J. Ellroy Brown’s Requiem 74: My case had blown sky high, the two people I had vowed to protect were in grave danger.