As perhaps the strongest El Nino on record declines, it may well be that by autumn could be swinging back to La Nina - with water cooler in eastern Pacific, warmer in the west.
Possible because this has happened with previous El Nino events; also now report of cold water below Pacific moving towards east, set to reach surface:
For Hong Kong, can be impacts including with more chance of typhoons nearby [or right over...]:
During La Niña, tropical cyclones in August-October are likely driven by an anomalous steering flow into the South China Sea and hence more tropical cyclones are likely to affect Hong Kong compared to the ENSO-neutral state.
Some chance, too, Hong Kong will be drier than normal in late summer and autumn, with somewhat cooler autumn and winter.