Extended periods of heat when you have very high temperatures throughout the day and even in the evening, the metal of the track actually expands, explains Gary McNeil, President of GO Transit. Track gauge can change, meaning trains travelling at high speeds could begin to wobble.
As a proactive safety measure, train operators will issue a slow order on very hot days. So far this year, GO has issued six: June 29, July 4, 5, 6, 12, and 13. It means trains that usually travel at a peak speed of 80 km/h on a certain section of track would reduce to 60 km/h, tacking on an extra few minutes to the trip.
