The Observatory cancelled the amber rainstorm warning at 8pm on Thursday, after heavy rain affected Hong Kong for much of the day.
However, the forecaster said people should remain vigilant about potential river flooding.
Data from the observatory showed that in the 24 hours leading up to 7.45pm, much of the SAR recorded rainfall of more than 70mm.
The western part of the New Territories was hit the hardest, with rainfall of at least 300mm recorded in Tsuen Wan, Ma Wan and parts of Tsing Yi.
The red rainstorm warning was issued three times within a 13-hour period, with the government suspending classes at schools for much of Thursday, and on Friday as a precaution.
The observatory said the downpours were associated with the remains of tropical storm Danas.