Ottawa Race Weekend organizers have changed the start times for two of its races this weekend to try to avoid the overwhelming heat and high humidity. Saturday's 10 kilometre race will start at 7 p.m. instead of 6:30 p.m., while Sunday's half marathon will start at 8:15 a.m. instead of 9 a.m. An important message to all runners this weekend: please fill out your race bib. Environment Canada predicts Sunday's temperature will reach a high of 31 C.Organizers say they could still stop the races if medical operations become overwhelmed. Ottawa paramedics said runners need to listen to their bodies and slow down or cool off during the race if they're not feeling well.

Source: CBC News May 28, 2016 15:00 UTC