Cuomo said it was too soon to determine whether the pandemic had reached its apex.
"We could either be very near the apex, or the apex could be a plateau and we could be on the plateau right now," Cuomo said. "You can't do this day to day. You have to look at three or four days to see a pattern."
The state reported 594 new coronavirus deaths on Sunday — a small decrease compared to the 630 new fatalities announced the day before. ICU admissions and intubations were also down, the governor said, while the discharge rate from hospitals was rising.
Cuomo sounded cautiously optimistic even as he urged New Yorkers to remain vigilant and continue adhering to the strict social distancing policies in place.
"The coronavirus is truly vicious," he said. "It's an effective killer. People who are very vulnerable must stay isolated and protected."
New Yorkers hunkered down Sunday as the city entered what authorities called a critical phase of the crisis. Those venturing outdoors for groceries or exercise largely heeded the city's new guidance to wear face coverings such as scarves or bandannas — a sight far less common a week ago.
Here are the latest coronavirus developments in New York:
OVERBURDENED HEALTH CARE SYSTEM
The governor said the state's health care system remained over capacity, adding New York is "running short on supplies all across the board." More than 122,000 people have tested positive for the coronavirus and at least 16,000 people remain hospitalized.
"The operational challenge for the health care system is impossible," Cuomo said. "It's not an exercise. It's not a drill. It's a statement of reality."
The federal government was deploying 1,000 doctors, nurses and respiratory technicians to New York, including 325 scheduled to begin arriving in New York City as early as Sunday.
The statewide balance of coronavirus cases has been "relatively stable" over the past few days, Cuomo said, but officials were tracking what they called a shift to Long Island. Nassau and Suffolk counties together have more than 26,000 cases.
New York City Mayor Bill de Blasio reiterated his call for a federal enlistment of health care workers, citing an anticipated "huge growth" in the number of COVID-19 cases in the coming weeks.
He told CNN Saturday night the city is going to need 45,000 doctors, nurses, respiratory therapists to get through the crisis.
"It's going to be very tight going into next week," the mayor said, adding the city still needs more ventilators.
SPRING BREAK SCRAPPED
The city canceled all of spring break for its public schools and, in a controversial reversal, called for classes to be held on the start of Passover and Good Friday. School officials announced the decision Friday, saying it was important to keep remote learning uninterrupted.
The announcement roiled the city's teachers union.
"No matter how angry and frustrated we are right now, we must focus on the most important thing, which is to get through the crisis," Michael Mulgrew, president of the United Federation of Teachers, said in a letter to his members. "I am sadly sure that there will be many more tough challenges in the days and weeks to come."