The setup I'm watching for a VIX play

Most traders watch VIX rip on a selloff and assume single-stock vols are doing the same thing.

They're not. And the gap is one of the most exploitable patterns in index options.

It comes down to what we call correlation skew.

When the index sells off hard, index ATM vol rises faster than single-stock vol. The S&P has a steeper put skew than most individual names. As spot rolls down the strike ladder, index implied vol climbs more than the weighted average of the single-stock vols.

That mismatch is the relative vols causes implied correlation to rise.

Implied correlation goes up when markets go down. Even before realised correlation picks up. It's a function of the skew differential, not what stocks are doing yet. (Though if the selloff is dramatic enough, realised follows).

When we bounce, the reverse plays out. Index vol rolls back down the skew faster than single-stock vol. Implied correlation collapses.

Here's why this matters right now.

This week is huge for earnings. A lot of heavyweights reporting. Their IVs reset lower once those events clear, which creates room for index vol to drop too.

VIX puts may be a nice play soon. Not yet. But this is the setup I'm watching.

If you can't see correlation moving inside the vol surface, you're trading the index blind.