Cold Water, Warm Weather: Why Lake Ontario Still Demands Respect

May has finally warmed up. Lake Ontario, not so much.

Water temperatures around Toronto are often only 5–10°C in spring, and the lake stays cold well into early summer and again in the fall. Falling into water that cold can trigger cold shock: gasping, rapid breathing, and a loss of control in the first minute. Within about ten minutes, strength and coordination in your arms and legs fade, which makes it hard to swim or climb back into a boat, even for strong swimmers. A capsize that is a laugh in July can become an emergency in May or October.

Before you launch

• Dress for the water, not the air. Wear a wetsuit or drysuit, even on a hot, sunny day.
• Keep your PFD on and fastened whenever you’re on the water.
• Don’t sail alone. Stay near others, and let someone ashore know when you’re heading out and when you expect to be back.
• Know how to recover from a capsize and re-board your boat. Practise it when conditions are calm.
• Check conditions first. Our weather page has links and a webcam.

In an emergency

Dial 911 (Paramedic/Fire/Police). Regatta Road has few landmarks and limited lighting, which can slow response, so tell the dispatcher exactly where you are and, if you can, have someone meet responders at the entrance.

Cold water safety matters, even on hot sunny days.