The category one cyclone was moving west southwesterly at 53 kph and is now in the Coral Sea.
The potential for Tropical Cyclone Iris to further intensify and move back towards the Vanuatu group was low, according to the Vanuatu Met Service.
It said gale force winds of 75 kph are expected to weaken as the system continues to track further west southwest in the next 6 to 12 hours.
However, heavy rainfalls and possible flash flooding expected over low lying areas and areas close to the river banks including coastal flooding expected over northern and parts of the central islands.
Seas will remain rough with heavy swells over northern and central waters.
The severe weather warning remains current for northern and central islands. Marine strong wind warning is also current for northern and central waters.