The daily chart of SPX is still quite convincing, in my opinion, of favoring a continued upward trend.
Positives: 1. Moving Averages are still on favorable trajectories. 2. MACD still favorable for continued strength. 3. Consistent trending within a tight channel. Negatives: 1. Over-extended from the years-long trendline of highs. 2. MACD seems like it may want to turn downward. 2. RSI deep in oversold territory.
Watching for: 1. RSI to reverse and move back towards the baseline. 2. MACD to remain strong. 3. Moving Averages to remain on trajectories, with minimal convergence.
If price action breaks below channel, I would watch for a test of the long-term trendline. Possibly in the 3800-3900 range.