Fact Sheet

Extreme Summer Heat’s Impact on Transit

Our goal is to get customers to their destinations in a safe, timely manner - no matter what the weather. When extremely hot temperatures descend on the Greater Toronto and Hamilton Area, weather-related delays can occur due to the extreme heat. We plan ahead with a proactive approach to monitor our rail corridors and equipment to minimize the impact to customers – keeping in mind safety is always our top priority.

What is Metrolinx doing to address the impacts of extreme heat?

During periods of extreme heat, Metrolinx will increase inspections of our equipment and rail corridors. Despite these increased checks, engines and HVAC systems can sometimes fail as they get overtaxed in the extreme heat just like other equipment and vehicles do. We will endeavour to make repairs efficiently and as quickly as possible. In addition, we will keep our doors open later so those affected by the heat can take a break in our air conditioned buildings.

What are sun kinks or “thermal expansions”?

Rail expands in the heat and contracts in the cold and in extreme heat, excessive expansion can lead to a rail kink which can cause a safety hazard. A rail kink is a slight or severe misalignment in the rail. If we experience a rail kink and continue to operate trains at high speed, we increase the likelihood of a complete rail buckle, which then would stop all rail traffic on that track.

Why do we have rails that are prone sun kinks?

In Canada we experience both extreme cold and extreme heat. Steel rails have a range of 60 degrees. The rails in Canada are built to function between the – 30C and +30C. So when the mercury rises above 30C, over a period of two or more days, the rails are prone to expand and the risk of sun kinks increases so we slow the trains down when the potential for sun kinks is high.

How do we avoid sun kinks?

There are a couple ways to address rail kinks, including stopping the service until the weather cools down - creating significant impact to service - or implementing a speed restriction and continue to operate under close supervision. Any sun kinks are repaired as soon as possible by replacing the piece of rail. Repairs are made over night or early morning during non-service hours.

Why do GO and UP Express have heat related speed restrictions?

Heat related speed restrictions are unavoidable during prolonged periods of extreme heat. If a rail kink occurs and is not managed correctly, the kink has the potential of becoming a complete rail buckle creating a significant safety hazard. And we never compromise safety for speed.

Learn more here: What gives?

How can you keep informed during extreme weather?

If a train is delayed, we let customers know within minutes the reason for the delay and how long it is expected to take. If a train is cancelled, we work quickly to let customers know what alternate arrangements are being made to get them where they are going.

  • Sign up for GO Alerts, this e-news system will deliver updates directly to your email account
  • Check www.gotransit.com for the latest information in real-time about GO’s operations.
  • Our Customer Service Ambassadors (GO) and Guest Services Representatives (UP Express) can answer questions and provide the most up to date information.
  • Union Station Monitors, 57 electronic display monitors at Union Station display the latest information.