From 11:45 p.m. tomorrow (Friday, September 2) until 5:00 a.m. Sunday, September 4 (so, effectively, all day Saturday, September 3) there will be no service in either direction between Manhattan and Brooklyn on the 4/5 line (so no 4/5 service at Borough Hall) as 4 trains will be stopping and originating at Bowling Green in Manhattan, and 5 trains do not serve Brooklyn at night. Use 2 or 3 trains as an option. All other lines making local stops should be running normally through the Labor Day long weekend. Update: While the MTA has cancelled most service changes over the weekend because of Hermine, the cancellation of 4 train service from late tonight to early Sunday morning remains in effect.
From 11:45 p.m. to 5:00 a.m. each night, Tuesday, September 6 to Friday, September 9, Manhattan bound A trains will be diverted to the F line between Jay Street-Metro Tech and West 4th Street. This means no Manhattan bound service at High Street during these hours, as C trains do not run late at night. To reach destinations in Manhattan below West 4th, use the 2, 4, or N, which replaces the R late at night.