The SPX 500 and NASDAQ 100 yesterday marched to record highs while the Dow 30 is less than 5% away from a record. However, what is interesting to note is the daily chart of US CBOE VIX. See in the chart below that VIX has started rising over the last few days.
At present, a rising VIX indicates that option traders are getting nervous about the markets. If VIX continues rising, expect volatility to pick up in the US markets in the days ahead.
Keep a close watch on this space.