A humidex advisory remains in effect as Torontonians brace for a week of sweltering heat and humidity.

Hot and humid conditions blanketed the city on Monday, bringing a daytime high of 34 C and humidex values of 39 to 42, Environment Canada said.

In addition to some rain in the morning, there is a 70 per cent chance of showers early this evening, with the risk of a thunderstorm, Environment Canada said.

The overnight low will be 22 C.

And don't expect any significant relief from the heat for the rest of the week.

If the heat isn't your thing, the most comfortable day of the week may be Tuesday, when humidex values drop to the low to mid-30s and the temperature reaches 29 C, Environment Canada said.

After that, daytime highs will hover in the mid- to high 30s for the rest of the week.

Thursday will be a scorcher, with a forecasted high of 37 C.

Sunday's scorching temperatures broke records.

The temperature hit a record 35.2 C, breaking the previous July 17 record of 34.4 C, which was set in 2002.

Stay safe

In hot, humid conditions, there is a risk of heat stroke and sun stroke.

Seniors, children and pets should never be left in a vehicle, even for a few minutes with a window down, on extremely hot days because the inside temperature of a car can be several degrees warmer than the air outside, Environment Canada said.

Despite the extreme heat, Toronto EMS said they had not received any specific heat-related calls as of noon Monday.

Here are some tips to keep in mind in times of high heat and humidity:

- Check on family members, friends and neighbours, especially isolated adults, seniors and people with chronic and pre-existing illnesses.

- Drink lots of water or natural fruit juices – do not wait to feel thirsty.

- Go to air-conditioned placed, including shopping malls, a library or community centre.

- Wear loose-fitting, light-coloured clothing made of breathable fabrics.

- Stay out of the sun.

- Reduce strenuous physical outdoor activity, especially between 11 a.m. and 4 p.m.

- Wear sunscreen if you venture outdoors.

People with heart or lung conditions, seniors and children should pay attention to the air quality health index level.

The city is encouraging landlords of buildings without air conditioning to provide a cooling room for residents to escape the heat.

Anyone who needs assistance or has heat-related inquiries can call the Canadian Red Cross at 416-480-2615.

Click here for a map of public cooling centres and public places that have air condition.

Pet safety

The so-called dog days of summer can be dangerous for pets, too.

People shouldn't expose their cats or dogs to the heat for extended periods because they could be at risk of heat stroke, according to the Ontario Society for the Prevention of Cruelty to Animals.

Dogs should only be left outdoors for short periods, should have plenty of water and a cool, sheltered place to rest that is out of direct sunlight, the OSPCA said.

Walks should take place in the early morning or evening when it's cooler outside.