6/10/17 was a very strange day in the markets. There are plenty of places to read about the causes (here for example). Essentially tech led a very nasty volatility move up in the middle of the day. Whats really strange is that this happened just as the VIX hit ~25 year lows and the S&P500 hit all time highs around 2445. You can see the highlighted point below.
Here is Amazon stock chart as an example from Business Insider:
This to me is showing how volatility and stock price are decoupling. From peak to trough the VIX moved up 27% in just a few quick hours, and closed ~+5%. The “NASDAQ VIX” (symbol VXN) was up over 30% and closed there. You can see in the chart below how large and fast that move was.
Yes, the NASDAQ index was down 2.5% for the day, but the S&P500 was dead flat.
I think this is a sampling of whats to come. Major volatility moves relative to actual index price moves.