Toronto Public Health is encouraging people to limit their exposure to the sun as the temperature and humidex values soar during another spell of sizzling weather.

Because of the hot, humid and hazy weather, the City of Toronto issued a heat alert Monday. A humidex advisory is also in effect.

Environment Canada says Monday’s high will be 33 C during the afternoon, but it will feel more like 40 to 42, except near Lake Ontario, where the heat and humidity will be a few degrees lower.

The UV index will be 10 or very high, meaning people should limit their exposure to the sun's rays.

Children and pets should not be left in parked vehicles or in direct sunlight.

Scorching temperatures and oven-like humidex values in the 40s are expected until the weekend.

CP24 meteorologist Bill Coulter said Toronto may get its first official heat wave of 2013 this week.

Environment Canada defines a heat wave as three consecutive days when the maximum temperature is 32 C or higher.

Highs of 33 C are expected Tuesday and Wednesday.

Thursday will bring a high of 32 C, followed by 30 C on Friday before the weather cools off on the weekend.

In its long-term forecast, Environment Canada is predicting a high of 25 C for both Saturday and Sunday.

Rain and/or thunderstorms are possible during the week.

Normal temperatures for this time of year are highs of 27 C and lows of 17 C.

Toronto Public Health says people should follow these tips to stay cool:

  • Drink lots of cool water
  • If you don’t have air-conditioning at home, go to a shopping mall, library or community centre
  • Wear loose, light-coloured and breathable clothing and when outdoors wear a wide-brimmed hat
  • Avoid the sun and stay in the shade or use an umbrella
  • Plan outdoor activities during the cooler parts of the day
  • Take cool showers or baths, or use cool wet towels to cool down
  • At home, keep blinds or drapes closed to block out the sun
  • Make meals that don’t require an oven
  • Put a fan next to a window to bring cooler air in from outside

Toronto Public Health offers these tips to keep pets safe and cool:

  • Provide plenty of fresh water
  • Limit your pet’s exposure to the sun to avoid sunburn
  • Use air-conditioning or a fan to keep your home cool
  • Provide shade if your pet ventures outdoors
  • Never leave a pet unattended in hot weather on balconies or in unsheltered backyards
  • Overeating during hot weather can lead to overheating, so let your pets eat less
  • Take dogs for walks during the cooler parts of the day
  • Signs of heat stroke include rapid panting, lots of drooling, hot skin, twitching muscles, vomiting and a dazed look

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