Risk assets may face stormier conditions if the Federal Reserve cuts interest rates, as expected, on Sept. 17. That's the message from futures tied to the VIX index, a measure of expectations of volatility in the S&P 500 over the next 30 days. The index, also called Wall Street's fear gauge, is calculated in real time from prices of options on the S&P 500, and reflects how much investors expect the market to swing, with higher values indicating greater levels of uncertainty. The spread between the Octobe ...