Rescuers are still deciding how to extract 12 boys and their football coach from a cave network in Thailand as forecasts for fresh rain have turned the operation into a “race against the water”.

A Thai official on Thursday said he had asked for 13 diving kits to be prepared while navy SEAL divers were assessing if the youth football team were fit enough to be extracted from the cave early.

“Our biggest concern is the weather. We are calculating how much time we have if it rains, how many hours and days,” Chiang Rai Governor Narongsak Osatanakorn told reporters.

Renewed flooding could add further complications to an already risky rescue operation.

On Wednesday, Narongsak had said that the boys, aged 11 to 16, and their 25-year-old football coach had been practising with wearing dive masks and breathing.

The football team became trapped kilometres deep inside the Tham Luang cave system 12 days ago after floodwaters caused by heavy rains blocked the entrance.

A Thai official on Thursday said he had asked for 13 diving kits to be prepared [Linh Pham/Getty Images]

‘Fraught with perils’

Teaching the boys how to dive is one of the options that has been floated for the rescue operation, but experts have pointed at the many risks involved.

“It seems that’s fraught with perils because cave diving’s not like normal open water diving,” British Cave Rescue Council Vice Chairman Bill Whitehouse told Al Jazeera.

Some areas in the cave complex are so narrow the boys, who cannot swim and do not have diving experience, would have to swim through the muddy waters unaccompanied.

It currently takes rescuers, who are seasoned cave diving experts, about six hours to reach the ledge where the boys are holding out.

Other possibilities for getting the football team out are finding an alternative entrance to the cave through shafts in the mountainside or waiting until water levels drop until they can walk out.

With monsoon season typically lasting until October, that could still take months.

Narrow corridors make the 10km Tham Luang cave system difficult to navigate [Al Jazeera] Narrow corridors make the 10km Tham Luang cave system difficult to navigate [Al Jazeera]

Good morale

The team is now accompanied by several divers and medics.

Videos released on Wednesday showed the boys laughing and saying they were “in good health”.

Kobchai Boorana, deputy director-general of the Disaster Prevention and Mitigation Department, said the rescue team would decide whether and when the boys would be sufficiently strengthened to make the journey out.

“Their conditions, we can see that their morale is good but what about their strength and their ability? That’s up to the team inside to decide,” Kobchai told reporters on Thursday.

“Our job is to keep pumping out water and it is up to the team inside to assess the safety level and whether the kids can travel safely through,” he said.

Thai authorities are pumping water out of the cave around-the-clock in hopes of lowering water levels inside the cave.

‘New life’

A British team of divers were the first to reach the boys and their coach on Monday evening at about 10:00pm (15:00 GMT).

“How many are you? Thirteen? Brilliant,” a diver is heard saying in video footage that shows the moment the boys were found perched on a ledge inside the cave complex.

Video footage released on Wednesday showed the boys in good spirits [Royal Thai Navy/EPA-EFE]

There had been no contact with the team since they got trapped inside on June 23.

Kian Kamluang, the mother of 16-year-old Pornchai, said hearing the news the boys were found was “like he has been given a new life”, she told the AP news agency.

She added she would never let her son go into a cave or near water again.

It took divers days to make painstaking advances in the dark, flooded cave, with rising waters at times forcing them to retreat.

The 12 boys belong to the local Moo Pa, or Wild Boar, football team and their coach had taken them on field trips before.