"I think what we are seeing today is incredibly encouraging and pleasing but there's a long way to go," he told reporters in Sydney on Sunday.
"It's going to be a difficult three weeks."
NSW posted 34,660 new cases on Sunday along with a further 20 virus-related deaths, bringing the seven-day fatality total to 141.
While more people are dying than at any time during the pandemic, Mr Perrottet says it appears the crisis is in fact tracking better than expected.
NSW hospitals are now caring for 2650 COVID-19 patients. Of these, 191 are in intensive care beds. At the depths of the Delta outbreak last September, there were 244 virus-infected people in ICUs.
Recent worst-case scenario modelling suggested 6000 people would be hospitalised at the apex of the outbreak, with 10 per cent of those patients in intensive care.
Even the best-case predictions painted a grimmer picture than reality, allowing for almost 3160 people in care.
Mr Perrottet says a full re-assessment of the forecast data will be conducted later in the week.
"We've gone through the last two years and we'll get through Omicron as well," he said.
"We have a highly vaccinated population, we have a less severe disease but one that is more contagious and it is pleasing to see that those numbers aren't increasing at an exponential rate."
Mr Perrottet says while the state is 95 per cent vaccinated, around half the patients in intensive care are not. Of the 191, 61 currently require ventilation.
"So the evidence, the facts, are very, very clear," he said.
"Vaccination helps protect you and your family and your friends and the wider community. So please continue to make that effort."
Some 93.8 per cent of all NSW adults are now double dosed, while 25.4 per cent have also received a booster, representing about 47 per cent of those eligible.
Of children aged 5-11, 11.5 per cent have had a single dose of vaccine.
Health Minister Brad Hazzard warned people not to forget the importance of a third jab.
"The booster is showing itself to be one of the vital tools in pushing back against the evil of this virus," he urged.
"It ... does make a huge difference to both ensuring you can fight back ... and reducing the likelihood you'll end up in hospital.
"It definitely reduces the likelihood you'll end up in ICU and reduces the chance of death".
Mr Perrottet also apologised for ongoing disruptions to food supply networks and delays at PCR testing sites, saying the latter had now begun to "largely resolve and subside".
