Here is a chart of the S&P 500 since the end of the great recession decline of 2008.  The price channel gives the range of possible values for what appears to be a developing market top and decline.  The formation in the circle shows two tries at higher prices and this is often followed by another try which would form a classic head and shoulder’s pattern. 

A rally from the current levels is certainly possible, even likely, but any significant negative events can drive stock prices down to the lower half of the price channel shown.

Keep in mind that stock market prices and trends look out ahead of current economic conditions which are still strong.