The S&P 500 on the D1 time frame was in a long down trend that started at the end of August. A last lower bottom formed on 13 October at 3492.4.
A closer look at the Momentum Oscillator reveals a positive divergence between point “a” and “b” when comparing the lower bottoms at 3581.7 and 3492.4. This could have alerted technical traders of a possible momentum reversal.