The indicators at the top of my head that represent volatility are
- Average True Range (ATR)
- Bollinger Bands (BB)
- Average Directional Index (ADX)
For ATR - you can utilize this by checking the distance of the ranges. If it's small, volatility is low. If it's high, then volatility is high. So you are looking for a low value of ATR
For BB - you can check the distances between the two Bollinger bands (HIGH BB and LOW BB) and it would indicate low volatility. It would say that the current action is sideways.
For ADX - quite similar to ATR in some sense. Same thought, lower value means absent trend.