Cyclone Maila upgraded to Category 4, as PNG and Solomons brace for more

Severe Tropical Cyclone Maila has been upgraded to a Category Four system, as it hovers over the Solomon Sea and is forecast to track back towards PNG's mainland later this week.

Australia's Bureau of Meteorology first announced the upgrade this evening, closely followed by the two countries most affected by Maila so far, Solomon Islands and Papua New Guinea.

Roads have been flooded and bridges taken out in provinces in PNG's Niugini Islands region, while coastal communities have been inundated by storm surges in the west of Solomon Islands.

The Governor of PNG's West New Britain, Sasindran Muthuvel, said his province experienced heavy rain for the past four days. He said roads had been badly affected in numerous parts of the province.

"All the roads within Gloucester-Kandrian (district) are very badly affected. In fact, in our New Britain Highway, one bridge is almost like washed away, or it's in a very bad shape."

He said photos shown by his MP colleagues in East New Britain and Bougainville indicate other parts of the Niugini Islands region have been hit hard too.

"I can see very similar damage, like, it's just just high, I mean, high level of rain or heavy downpour that caused, because our drainage is already poor," Muthuvel said.

"So most of our drainage has been filled and water is on the road, flowing on the road, and some water is like flowing on top of the bridge, and that's when some of these main roads have been cut off."

Loop back

After forming at the weekend, and shrouding parts of PNG in rain and wind, Maila moved out of PNG waters into Solomon Islands waters by Tuesday, but was forecast to loop back towards PNG from Thursday.

Milne Bay province could be directly affacted, again, by the cyclone, with the PNG Weather Service urging people in Milne Bay to take any lull in the weather as an opportunity to get prepared.

RNZ Pacific understands the PNGDF is readying to deploy defence enginners out of Law to be on standby for rescue and recovery work as required.

It comes as several people, including a critically injured patient, have been missing at sea since last week after embarking from Woodlark Island as part of an emergency medical evacuation to Milne Bay's Alotau General Hospital in a 23-foot dinghy.

It is likely that PNG's government will be asked to help fix damages in numerous provinces, with Muthuvel saying the national cabinet stood ready to help once it received damage assessments from each province.

"The PM (Prime Minister) also mentioned that once they receive all the reports, then cabinet can deliberate on it and see how they can they can support.

"Actually, the Department of Works has more of a role to play in terms of trying to help with fixing those roads or fixing those affected bridges and all those things, because most of these roads have hardly any maintenance - that's one of the reason why some of these roads are badly affected," Muthuvel said.

Inundated

People in Solomon Islands' Choiseul Province are being urged to seek shelter on higher ground until Cyclone Maile moves away from the country.

Maila has been causing tidal surges across Western and Choiseul provinces with multiple videos of the ocean flooding being posted on social media.

The Provincial Police Commander for Choiseul Berry Pogesopa, who is also chair of the provincial disaster response, said whole villages including schools and a hospital had been impacted by ocean inundation.

Warning people against going to sea, he also said people should take shelter, including on higher ground.

Earlier, a resort owner in Western Province, said his main concern was for the thatched rooves of their bungalows. Joe Entrikin of Zipolo Resort in Munda said so far they'd had strong winds and heavy rains.