With temperatures set to plummet into the low 30s overnight, New York City has issued its first Code Blue of the fall season.

The weather emergency notice, which was issued by the city’s Department of Homeless Services, will go into effect starting at 4 p.m. on Tuesday and remain in place until 8 a.m. Wednesday, New York City Emergency Management said.

The Department of Homeless Services issues Code Blue notices when temperatures drop to 32 degrees or below between 4 p.m. and 8 a.m., with wind chill values taken into account.

Temperatures are set to hold steady in the low 50s during the day Tuesday before the season’s coolest air moves in during the evening hours. Lows are expected to drop into the 30s by Wednesday morning.

NY1 meteorologist Guy Brown said feels-like temperatures will dip into the high 20s Wednesday morning due to strong and continuous wind gusts.

“Outreach teams will canvass all five boroughs to connect our most vulnerable New Yorkers to shelters,” New York City Emergency Management said. “No one who is homeless and seeking shelter in New York City during a Code Blue will be denied.”

The city is asking New Yorkers to call 311 if they see someone experiencing homelessness who is in need of help.

Thursday’s forecast looks similar, though a Code Blue for that day has not yet been issued.