Today is Triple Witching Day but will it matter for the S+P 500?

Yesterday the S+P 500 rose to set a new all time high and then a new all time closing high. The index set a new record at 5,733.57 and later closed for the first time ever above 5,700, at 5,713.64. The index is just now priced to reopen a little lower this afternoon and that opening comes ahead of what is known in the trade as Triple Witching Day. This occurs 4 times a year on the third Friday of each futures settlement month (March, June, September and December). This is when a whole bunch of index futures, index futures options and derivative contracts all expire simultaneously. Sometimes that can have an impact on the markets and especially on the S+P 500. Now that is not to necessarily say in which direction, but it can cause a rise in volatility, if nothing else. Right now that is not evident in the S+P 500 futures this morning, but they are currently pricing a slightly lower opening, at around 5,707