Need to travel across boroughs on (and after) Doomsday? Here is the deal.

There is no 7 train service between Times Square and Queensboro Plaza this weekend due to repairs on the signal. The same will hold for the weekends of June 24 and July 29 as well. The signals, 50 to 90 years old, are in serious need of replacement according to the MTA.

F train service will be suspended from Jay Street to 18th Avenue, and G train from Hoyt Schermerhorn and Church Avenue. F and G trains are going under a rehabilitation on the nearly century-old Culver Viaduct over the Gowanus Canal.

From June 20th, 2011 through 2012, the Smith-9th Street station will be completely shut down for rehabilitation. F and G trains will bypass the Smith-9th Street station while the rehabilitation takes place.

Major changes in MTA subway service from May 20 11:30pm to May 23 5am:

No 1 train between 14St and South Ferry

Brooklyn Bridge-bound 6 trains run express from Grand Central to Brooklyn Bridge

No 7 train between Queensboro Plaza and Times Square

Jamaica-bound F trains skip 14ST and 23St.

More info on the MTA website.