This is a cash chart of the S&P 500 index. That blue line in the middle panel is the McClellonOscillator or $nymo When that number gets to +100 or -100 you should not be trading against that direction. You look for a reinforcing mechanism.
The bottom panel is Stochastics. Those are oversold. You should not be looking to short when that is happen AND $nymo is near 100. $nymo was plotting -100 intraday yesterday. It did not close on that low, but it was close enough