It's shaping up to be an intensely hot week over parts of Central Canada, as southern Ontario and southwestern Quebec face a possible heat wave.

Temperatures are expected to rise "well into the thirties," Environment Canada forecasts, with the humidity making it feel like 40 C or more.

"This will make for very uncomfortable conditions," the federal weather agency said in a special statement for Ontario covering a band from Windsor to Ottawa.

"It is advised to stay in an air conditioned place or seek shade when possible, drink plenty of water and limit physical outdoor activity."

Southwestern Ontario is forecast to see the mercury climb above 30 C on Monday, while London, Hamilton and Toronto won't reach those sweltering levels until Tuesday.

The heat will drift to Ottawa and Quebec's Gatineau region by Wednesday.

"Nighttime temperatures will not drop below 22 C for many, so some uncomfortable days and nights are ahead," CBC meteorologist Johanna Wagstaffe said.

Further into Quebec, the area from Val d'Or east to Trois-Rivières will be affected, with temperatures solidly in the high 20s midweek and a few days above 30. Montreal could see a peak of 33 C on Wednesday and Thursday.

The heat will reach as far as the East, with Fredericton and St. Stephen, N.B., forecast to reach 30 C on Wednesday.

"Basically, from southern Ontario to the Maritimes will be hitting the 30s over the next two to three days, though southwestern Ontario will see the longest of the heat event," Wagstaffe said.

She said humidity warnings will probably be issued in Ontario as the humidex rises above 40 C, and possibly in Quebec as well.

Individual cities can also disseminate heat alerts, triggering relief measures. If Toronto issues one, it would be the city's third of the season.

Montreal public health officials said they expect a heat warning as early as Tuesday. Norman King, an epidemiologist with Montreal Public Health, advised people to seek out air-conditioned spaces, reduce physical effort and drink a lot of water during the extreme heat. King said vulnerable groups like the elderly and people with respiratory problems should pay particular attention to these measures.

CBC Ottawa climatologist Ian Black counselled residents of the national capital to "find a cool spot" to evade the heat. "Air quality may also decline, and there may even be some thunderstorms at times," Black said.

A cold front will finally blow in on Friday to provide some relief in southern Ontario, while Quebec will see the heat persist through Friday, Environment Canada said.

A heat wave in Ontario is defined as three days of 32 C or more; in Quebec, it's three days of 30 C or higher.

Flood warning in B.C.

Elsewhere in Canada, two low-pressure systems over the Prairies could bring severe thunderstorms to southern Manitoba and Northern Ontario on Monday afternoon, while a flood warning and flood watch are in place for parts of British Columbia.

Most of the Prairies have a risk of rainstorms for Monday, but Manitoba-Ontario border is in line to see the brunt of it. Alberta is also expected to be doused by widespread rain showers.

In B.C., a rainfall warning for the Interior has been lifted, but river levels across much of the region were still rising quickly due to the weekend's precipitation plus rapid snowmelt.

The province's B.C. River Forecast Centre said the Shuswap River was rising two centimetres per hour in the village of Lumby on Sunday afternoon, and placed a flood warning on parts of the waterway. A flood watch was in place for other stretches of the river, as well as the North Thompson and South Thompson rivers and the Cariboo region, where up to 50 millimetres of rain fell Saturday and Sunday.

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  • Everyday Wear

    <strong>True or False: </strong> Sunscreen isn't needed on a cloudy day.


    Up to 80 per cent of the sun's rays can penetrate clouds, mist and fog, so even if you can't see the sun, it can still see you!

  • Stay Out Longer

    <strong>True or False:</strong> A sunscreen with an SPF of 30 means you can stay out in the sun 30 times longer without burning.

  • TRUE

    SPF indicates how much longer you can spend in the sun without burning, compared to having unprotected skin. The amount of time varies from person-to-person depending on your skin type. For example, if you have fair skin and tend to burn in 10 minutes without sunscreen, then a SPF 30 will protect you 30x's longer -- or a total of 300 minutes for the day -- assuming you are applying the sunscreen every two hours. Sunscreen reapplication does not provide you with an additional 300 minutes of protection; it just provides the original 300 minutes. Those who tend to burn more easily should use a sunscreen with a higher SPF, especially when out in the sun for long periods of time.

  • Proper Amount Of Sunscreen?

    <strong>True or False: </strong> Wearing the proper amount of sunscreen during peak hours (10 a.m. to 2 p.m.) is enough to protect you from the sun.


    Wearing the proper amount of sunscreen with the correct SPF for your skin during peak hours is a great first step in sun protection. However, extra measures are required to fully protect yourself during the sun's strongest time period. Limiting sun exposure (such as seeking shade or using an umbrella), wearing protective clothing and, of course, using sunscreens may reduce the risks of skin aging, skin cancer and other harmful effect of the sun.

  • 365 Days A Year?

    <strong>True or False:</strong> Sunscreen is just like a pair of white pants: you bring it out for the May long weekend and you can put it away after Labour Day.


    Although the sun may not feel as warm before May and after September, UVA rays are just as strong all year round. UVA rays are not affected by time of day or season. It is important to wear sunscreen every day, all year round to avoid the long-term effects of the sun.

  • Fair Skin?

    <strong>True or False:</strong> Only those with fair skin are at risk for skin cancer and need to use sunscreen.


    Although your skin type can help dictate the amount of time you can stay in the sun without burning, those with darker skin need to remember they are not immune to the effects of the sun, and damage can occur even without burning. There are a number of other risk factors that can increase your chances of developing skin cancer: not using sunscreen; working, playing or exercising in the sun for long periods of time; having one blistering sunburn as a child; and taking drugs that make you more sensitive to UV light.

  • Skin Cancer

    <strong>True or False: </strong> Both UVA and UVB rays can cause skin damage and skin cancer.

  • TRUE

    Although they impact the skin in different ways, both types of UV rays can cause serious skin damage. UVA rays penetrate your skin more deeply, causing premature aging and long-term skin damage, such as wrinkles and sun spots. UVB rays penetrate the outer layer of your skin and are responsible for sunburns. Too much of either can eventually lead to skin cancer.

  • All The Same

    <strong> True Or False:</strong> All sunscreens are the same -- as long as you're wearing one, you'll be well protected from the sun.


    All sunscreens offer some protection from UVB rays (preventing sunburns), but not all protect against UVA rays (those rays that penetrate your skin more deeply). Proper application of a "broad spectrum" (with both UVA and UVB protection) sunscreen, like most Banana Boat products, is the best way to defend your skin against both the immediate and long-term effects that the sun's rays can have on your skin.

  • Protection

    <strong>True or False:</strong> Photostable sunscreens provide protection that won't break down in the sun.

  • TRUE

    UV rays have so much energy that they can actually break apart some sunscreens over time (just like the sun can damage your hair, skin, carpet, curtains, etc.). When this happens, sunscreens lose their ability to absorb UV rays, leaving skin unprotected. Photostable sunscreens resist this degradation so your skin is effectively protected.

  • In The Morning

    <strong>True or False:</strong> As long as you apply sunscreen each morning before going outside, you will be well protected from the sun.


    It is extremely important to re-apply sunscreen throughout the day to ensure full protection from the sun's harmful rays. Follow these rules for proper sunscreen application:<br>a. Apply early: Apply sunscreen at least 15 to 30 minutes before sun exposure.<br>b. Apply enough: Each time you apply, you should be using one ounce or 30mL of sunscreen -- this is roughly the size of a golf ball.<br>c. Apply everywhere: <a href="" target="_hplink">Don't forget ears, lips, shoulders and nose. These areas are most susceptible to sun exposure</a>.<br>d. Re-apply frequently: Be sure to re-apply one ounce of sunscreen every two hours, especially after swimming.

  • Sun IQ Score

    <strong>If you got 7 to 9 answers correct:</strong> <em>You Are A Sun Savvy Superstar!</em> Congratulations! It looks like you know your stuff when it comes to protecting yourself from the sun. While you passed the test with flying colours, your job isn't over yet. Use your knowledge of sunscreen to ensure your family and friends stay well-protected too, regardless of their skin type or age. <br><strong>If you got 4 to 6 answers correct:</strong> <em>You Are A Sun Safety Supporter</em> Although you are on the right track to learning your sun protection ABC's, you still have some facts to get caught up on. Practice the sun safety advice you've learned here and come back and take the quiz again. <br><strong>If you got 0 to 3 answers correct:</strong> <em>You Are A Serious Sun Slacker</em> You may like to have fun in the sun, but sooner or later you will get burnt. It's time for you to do your homework and understand the true consequences of leaving yourself unprotected against the sun's harmful rays.