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.
Later in the evening, New York City officials also reported a dip in fatalities. As of 4:45 p.m. it said deaths had risen by 218 since the evening before, to a total of 2,472. By comparison, there were 387 new deaths reported in the previous 24 hours and 305 the day before that.
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.
Mayor Bill de Blasio also found cause for encouragement, telling reporters that while the city still needs thousands more ventilators, its supply had outlasted earlier projections. Like Cuomo, he stopped short of declaring a turning point in the crisis.
"I see a few signs that are a little hopeful, for sure," he said. "But I think it's early to be able to declare that. Let's hope and pray, but we're not quite there yet."
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