UBS Warns Clients May Not Be Able To Trade After Brexit Vote
"Regardless of the outcome, we may see an increase in volatility and an impact on trading volumes. In the event that extreme market moves occur in an environment of limited liquidity, our spreads may widen, liquidity may reduce, and price may turn untradeable for a period of time."
June 21, 2016 Forex Crunch
Forty Forex Brokers Tighten Margins Ahead of Brexit Vote
All amidst the lowest realized volatility since August...
Bollinger band width (daily):
And the lowest monthly volatility in at least a decade...
Bollinger bands (red line):
"equities alternate between periods of low volatility, followed by periods of high volatility, and so on - much like the calm before the storm and the inevitable inactivity afterward."