The city is expected to spray parts of Queens and Staten Island for mosquitoes Monday night.
The spraying is set to begin at 10 p.m. and run through 6 a.m. Tuesday.
If the weather is bad, the spraying will take place Tuesday night during the same hours.
The health department has been spraying pesticide as a way to reduce the risk of the West Nile and Zika viruses.
Health officials say the Zika virus has not been found in any mosquitoes in the city, but they have seen an increase in the types of mosquitoes known to transmit the West Nile virus.
For more information including the areas being sprayed, go online to nyc.gov/health.