However, the official in immediate charge of the operation, Governor Narongsak Osatanakorn, indicated at a news conference that if heavy rains started and appeared to be causing flooded areas in the cave to rise again, divers would try to take the boys out right away. They are all strong.
"It's so sad to see where they are and we hope they get out safe and sound".
Others have criticised him for agreeing to take the young boys into the cave during the monsoon season.
Another, Tan, wrote: "Mum and Dad don't worry about me, I'm fine". Thank you for everyone's that come to help. His family are shopkeepers.
"Mom, Dad, Don't worry, I'm OK, please tell brother Yod to prepare to take me to eat fried chicken. Nick loves Mum, Dad and siblings".
"Don't worry, I'm happy", a boy named Tee wrote. "I'm OK. Please tell my teacher too". I love both of you.
"I'm afraid that the parents will begin to think the same thing will happen to their son", said Radap Tate, of the Navy SEAL's death on Friday. Mummy love (s) you and miss you so much.More news: Tropical Storm Beryl forms in Atlantic
"It doesn't matter how long I wait as long as he is safe".
"We are still in a war against water and time", he said.
Mr Narongsak, a former provincial governor, told reportersconditions were now "perfect" and the next three to four days was "the best and most ideal time for the rescue operation".
"We have to make a clear decision on what we can do", he told the French news agency.
Gong Hui, a Chinese diver involved in the operation that has drawn some 130 Thai and worldwide divers, told Reuters on Saturday before the fresh rains that water levels in the cave had "receded a lot" after sustained pumping had removed millions of litres of water.
The ideal scenario is for enough water to have been pumped out to allow them to climb out.More news: Israel Tells Khan Al-Ahmar Palestinians Leave by Friday
Katadzic has not dived the final kilometre to where the boys are stranded on a muddy bank, the most risky part of the dive, during which rescuers have to hold their oxygen tanks in front of them to squeeze through submerged holes. A team of bird's nest collectors scour the mountainside for openings.
Tate regularly visits Chanin's parents at the site of the cave where they keep a constant vigil.
The rescue mission could begin as soon as the weekend, but no decision has been made whether to proceed, the U.S. official said.
The boys are being trained in the basics of diving in case the floodwaters force authorities into a sudden evacuation.
Some areas in the cave complex are so narrow, the boys, who do not have diving experience, would have to swim through the muddy waters unaccompanied.
Mr Narongsak said the drills would have to pierce 600 metres of fragile limestone rock to reach the boys and rescuers were discussing drilling angles. Attempts to establish a phone line to the cavern where the boys are trapped have not yet been successful.
The death on Friday of a former Thai navy SEAL, Saman Gunan, underscored the risks of making the underwater journey. Workers have been trying to run an oxygen line into the cave's chambers.
He says: "The plan that I've held on to from the beginning is that we have to bring the kids out and the determining factor of this plan is to have as little water as possible".More news: Hurricane Beryl Is Tiny, Unpredictable