Mayor Bill de Blasio knocked price hikes for ride-share services as a historic snow storm is expected to hit overnight.
"It's the law that you cannot price gouge in the context of an emergency," de Blasio told reporters after he was asked about Uber and other apps. "It would be immoral to charge people extra because there is a natural disaster going on."
Minutes earlier,Uber sent an email to users that prices would not go over 2.8 times the normal fare during emergency conditions, still charging riders above average prices.
The email went out after Gov. Andrew Cuomo announced a state of emergency in the five boroughs in surrounding counties.
Rival app Lyft also warned its users that its own increased fares would be limited to double the normal cost.
By Monday at 2 p.m., Uber's dynamic pricing was already in effect.
Uber's hike is still in line with an agreement it made last July with the New York State Attorney General Eric Schneiderman to limit price increases during "abnormal disruptions of the market" — including natural disasters.
In a press statement, Uber also promised to donate 20 percent of fares with surge pricing toward the American Red Cross.
Uber came under fire earlier this month when New York City Council members proposed capping surge pricing at double normal rates.
At the time, an Uber representative testified surge pricing averaged 85 percent above normal rates.