Cook Islands Meteorological director Arona Ngari said tropical depression 15F (TD15F) was expected to pass through Rarotonga last night.
He said winds were expected to be strong and gusty, but would last only till this morning.
The potential for this system to develop into a tropical cyclone in the next 24 to 48 hours was “moderate”.
Nagari said the forecast for the next couple of days showed an active trough of low pressure with associated cloud and rain remained slow-moving to the north of the Southern Cook Islands, while a trough of low pressure was also slowly moving over the northern islands.
The forecast predicted strong northerly wind over the ocean with rain, squally thunderstorms and rough seas.
The forecast for Rarotonga is for occasional rain, heavy at times and few thunderstorms and moderately rough seas.