The FOMC (Federal Open Market Committee) was formed by the Banking Act of 1933, and consists of 12 members: the president of the Federal Reserve Bank of New York, 7 members of the Board of Governors of the Federal Reserve System, and 4 (of 11) Reserve Bank presidents, who serve one-year terms on a rotating basis.
The FOMC meets eight (8) times a year (every 6 weeks), to discuss/change monetary policy, review economic and financial conditions and assess and procure price stability and employment.
Four (4) of these meetings feature a Summary of Economic Projections (SEP) followed with a press conference by the chair.
The minutes are released three (3) weeks after the date of the policy decision.
The FOMC minutes are the most anticipated data release since US monetary policy affects global markets as well.
VOLATILITY is triggered before the release because any change in Federal Fund rates can directly affect multiple economic variables such as short/long-term interest rates (borrowing cost), foreign exchange rates (trade), employment rates (disposable income) and prices of goods and services (consumption).