From the link:
CNN Money’s “Fear and Greed” Index is at 97. That in itself is in the stratosphere. Extreme greed. It can’t go higher than 100. A year ago it touched 3, on a clock at swings both ways.
Still, the market can go higher, and probably will, since there is momentum in that 97 number. It usually takes a divergence (a high below a high) in that index to trigger a decent down swing (see the red circles on the chart below). The index has to back off then fail to go higher as the market does.
For more discussion and the Fear and Greed chart: