New York City officials on Monday announced the first drought warning in over two decades, as the city struggles with a "historic" lack of precipitation that's leaving reservoirs below their typical levels.

"Our city vehicles may look a bit dirtier, and our subways may look a bit dustier, but it's what we have to do to delay or stave off a more serious drought emergency," New York City Mayor Eric Adams said on Monday. "We need New Yorkers to continue to save water too, so we can water our parks and fill our pools this coming summer."

The warning, a classification below a full-on drought emergency, means city agencies will limit washing their vehicles, close illegally opened fire hydrants, survey plumbing leaks, and limit water going to artificial ponds and lakes, among other changes.

New Yorkers are also encouraged to take voluntary conservation steps like shorter showers and ensuring dish washers and laundry machines only run with full loads.

Water rate increases, fines, and sanctions on the public only begin if the drought status is raised to an emergency.

The warning comes as New York and its outlying reservoirs have received eight inches less of rain than usual, leaving the city with nearly 20 percent less water than expected this time of year in its reservoirs, according to officials.

The last New York City drought warning was in 2002.

The warning also means the city's Department of Environmental Protection will pause the final phase of its $2bn repar to the leaking Delaware Aqueduct, which brings down half of the city's water supply from the Catskill Mountains. To repair the aqueduct, officials shut down one of the four reservoirs that feed the tunnel, but that step will be reversed for the time being to allow more water into New York City. Repairs are expected to resume next year.

Ten additional New York counties, including much of the Hudson Valley, are under drought warnings of their own.

Fires have broken out across the region in recent days amid the unseasonably dry conditions, including a blaze in Brooklyn's Prospect Park and New Jersey's 3,000-acre Jennings Creek Fire, which was observable from space and sent smoke well into upstate New York. New York City alone has experienced 270 brush fires this month, a record, according to The New York Times.

The conditions, part of one of the worst droughts the region has ever seen, prompted New York City to ban grilling in public parks.