CHICAGO (CBS) — With dangerous cold temperatures expected both Wednesday and Thursday, both Metra and the South Shore Line will operate modified schedules.

Metra has modified the schedules for 10 of its 11 commuter rail lines on Wednesday and Thursday, operating fewer trains than normal. Only the Heritage Corridor, which already runs only seven trains a day, will use a normal weekday schedule on Wednesday.

In addition, on all Metra lines Wednesday and Thursday night there will be no outbound trains departing Chicago after 10:40 p.m. The last inbound trains are scheduled to arrive downtown Chicago by 10:49 p.m.

The new schedules will reduce the use of mechanical equipment, and cut down on moves through switch points in an effort to minimize stress on the tracks. Metra says the schedules are also designed to provide adequate service for predicted ridership.

You can find a full list of the modified schedules for each Metra line on the railroad’s website.

Meantime, the South Shore Line is adjusting its schedules Tuesday through Friday. On Wednesday and Thursday some normal morning rush hour trains into the city will not run. The schedule is subject to change, and officials urge commuters to check the South Shore website.

A handful of westbound trains will be canceled on all four days, and some other westbound trains will be bused between South Bend and Carroll Avenue.

For details on South Shore’s modified schedule, click here.

CTA has not announced any changes to its bus or train schedules due to the cold, but has encouraged riders to dress in extra layers, and stay indoors as long as possible while waiting for their bus or train. The CTA provides tracking information for its buses at ctabustracker.com, and for its trains at transitchicago.com/traintracker/