It might not be as cold as last years Polar Vortex, but some winter warning signs are popping up for the U.S. and global economy. Here are the three red flags spooking the stock market with the Dow dropping over 300 points at one point before closin down 187. They go deeper than the oil price meltdown that has received so much attention 1. Americans are pulling back on spending. Retall sales dropped 0.9% in December, the critical holiday shopping month, compared to November. It was worst monthly plunge since the Polar Vortex halted much business activity last January. Consumer spending drives the us. economy, so any major pullback is alarming, especially around Christmas Consider that experts were only predicting a 0.1% drop in December.