Walmart now sees net sales rising 3.75% to 4.75% from last year, compared to prior guidance for a range of 3% to 4%. Walmart also tweaked its earnings forecast, saying it now expects adjusted earnings per share to range from $2.52 to $2.62. The previous outlook was for $2.50 to $2.60.

The $100 level acted as support earlier in August. But since February, $100 has been a pretty strong resistance level. Now that WMT stock is below it once more, it is a worrying sign. Shares of Walmart rarely go on sale unless the market perceives a macro shock.

Stock index futures were muted on Thursday, a day after Wall Street ended mostly lower as investors continued to await Federal Reserve Chair Jerome Powell's speech at Jackson Hole on Friday.

Stocks closed significantly higher on Friday after Federal Reserve Chair Jerome Powell signaled a possible interest rate cut during a high-profile speech at an annual gathering in Jackson Hole, Wyoming.