Tropical Cyclone Lola has strengthened to category 4 with wind gusts of 198 km/h, the Vanuatu Meteorology and Geo-hazards Department says.

The cyclone is expected to hit Vanuatu's second largest city, Luganville, at midday.

Evacuation centres have been set in Lugainville as authorities tell communities to stock up on food and water and prepare to evacuate their homes in case of flooding.

Philip Meto, principal provincial Liason Officer with Vanuatu Disaster Management Office, said on Monday people are aware of the cyclone risks and evacuation centres had been set up.

He says in previous cyclones, in flood-prone areas "more than 100 people are usually evacuated".

Meto says their communications network is limited and urges people to access official updates on social media and continue listening to the radio.

Luganville Municipal Council is working with the Vanuatu National Disaster Management Office and people are advised not to go into work.

The council's evacuation team spokesperson, Colenette Tapi, says ward secretaries are "passing on information" and "making sure people are prepared."

"We are trying to get people prepared like stocking food and cutting down trees.

-RNZ.