The basic answer is that the two are only loosely related. But, as a rule of thumb, if news is good for investors it is usually increases the rate on a 30 Year fixed mortgage.
The rate for a 30 Year fixed mortgage is based on many factors, but one good indicator is the 10 Year Treasury Bond. As the value of the 10 Year goes up, the yield goes down and the price of the bond usually follows. So, if the Fed's reduce the Fed Rate, that tends to please investors and drive people into the stock market and out of the bond market. As a result, the price of the 10 Year Bond goes down, yields go up, and the rate of a 30 Year Mortgage goes up with it.... more