The New York City Department of Transportation warns of the slowest traffic of the year in Midtown due to the United Nations General Assembly, with average speeds dropping below 4 mph. Every weekday through Sept. 27 is a “gridlock alert” day. Streets like First Avenue and parts of 42nd Street are closed. Temporary bike lanes are provided, with plans for permanent ones. Traffic speeds are the lowest on record, impacting emergency response times. A detailed list of affected roads is available from the Department of Transportation.