Normally we would say 'You had better wait until tomorrow'. 'You can better wait until tomorrow' means that you are better able (than something or someone else implied by context) to wait until tomorrow. However, as a side note, your examples probably do not mean what you think they mean. You had better wait until they reopen tomorrow', but ' wait for them to reopen tomorrow' 'I think the supermarket is already closed.You wanted to go to the beach, but you had better wait until it clears up', but ' but you had better wait for it to clear up'

In some slightly modified examples, 'for' and 'until' would still mean the same thing, but would need you to phrase the sentence differently: The reason 'until' is slightly more correct is that 'tomorrow' is (in this context) acting as a time, rather than an object (for the arrival of which you might wait) or an event (for the occurrence of which you might wait). : Wait Until Tomorrow: An Evraft Novella (9781734509632) by Sauer, Jenni and a great selection of similar New, Used and Collectible Books available now at great prices.

For most purposes, they mean the same thing in this context. 'Until' is slightly more pedantically correct, but a native speaker would understand either, and might use either (or the abbreviated ''til', dropping the 'un-'). Like all mothers, mine had a set of maxims that she thought were important to impart to me: if you can't say anything nice, then don't say anything at all (unless it's irresistibly funny) it's as easy to fall in love with a rich man as it is with a poor man (a nice idea in theory) if you want to commit suicide, wait until tomorrow (advice which has, it turns out, saved my life).Like many. Either 'for' or 'until' would be idiomatic in both your examples.

Wait Until Tomorrow by Jenni Sauer