Market volatility has been high leading up to and including after the Brexit referendum results. The VIX has climbed up to around the 25 level which is above the average ambient temperature of 15, but not ridiculously high (last August, for example, there was a spike up to 50 and I’m struggling to remember what calamity was the order of that day).
The UK exiting from the EU causes uncertainty in the minds of money managers. Whenever uncertainty is high, the natural desire is to raise cash and reduce portfolio risk, so futures get sold. This triggers automatic liquidations of underlying equities and debt portfolios, which leads to broad-based asset price decreases as the liquidations occur. There also may be some margin liquidation going on for more over-leveraged players.
Eventually this vicious cycle ends – the trick is anticipating when the vicious cycle ends. I believe it will be sooner than later, although the choppyness of the market will continue to confuse most market participants into believing that we are either entering into the new dark ages, or a golden era of economic productivity when neither seems to be the case.