Cloud over Pearl Harbor hinders attackers and defenders differently

How would unexpected cloud cover over Pearl Harbor affect the Japanese attack?

It would disrupt Japanese orientation and formation, but it could also delay American visual detection of the raid.

The Japanese attack formed and oriented at altitude before individual aircraft descended toward their targets. Unexpected cloud could break visual references and make that positioning harder. Much of the final attack still occurred at low level, so the strike would not simply be canceled. The same cloud could also conceal the aircraft from American observers until later, producing a mixed effect rather than a clear advantage for either side.