USDJPY on D1 at 2017.10.31 00:00. The chart shows: that the fast average crossed below the medium average. This sign of short term momentum changing from up to down acts as a possible first sign of trend change from up to down, particlularly if there is an angular ‘elbow joint’ showing on the short term moving average, that the fast average has just crossed below the slower of three averages. Short term momentum is carrying the price down and is in the direction of the cross down – a possible second sign of trend change from up to down. Check also the angle of the elbow joint on the short term moving average which if very acute, can be a sign of strength in that direction (potential short). these signals firing off at the same time. Check the strength of the move, whether there has been a turn on strong resistance, a candlestick pattern, or test/restest off the top bollinger band or 20SMA and consider selling.
The chart is attached.