Holiday Halt: S&P 500, Nasdaq to remain closed for Juneteenth today after busy 'triple witching' session

US financial markets will be closed on Friday, June 19, for Juneteenth, granting investors a long weekend. This federal holiday's observance advanced the quarterly "triple witching" derivatives expiration to Thursday, June 18. The compressed schedule led to heightened trading activity as investors adjusted positions before the holiday break.