Postmedia and Star Staff
The massive “dome” of heat and high pressure settling over much of the continent this weekend could be aptly compared to “the lid of a frying pan,” according to Environment Canada climatologist and weather guru David Phillips.
The first major heat event of the summer is expected to bring balmy temperatures in the mid-30s across a swath of Ontario from Windsor up to the Greater Sudbury area and clear across to the Ottawa Valley, Phillips said.
But while the humidity will make things uncomfortable — it will feel closer to 40 degrees with the humidex — we won’t be smashing any records or feeling the brunt of the heat wave that has triggered warnings of dangerously high temperatures across much of the United States.
Environment Canada issued a heat warning for much of Ontario as the “Bermuda High” weather system makes its way north.
“I compare it to a sumo wrestler,” said Phillips. “It just stands there, you can’t move it, all the other weather systems just go around it, and it’s usually there for an extended period of time.”
The hot July sun bakes the air mass, which is then trapped by the band of high pressure as it rises. Instead of the hot air dispersing into the atmosphere, it’s forced back down to the surface by the sinking high-pressure system.
“I think the lid of a frying pan is a good analogy,” Phillips said. “The lid of high pressure forces the air not to disperse but to sink, and when it comes down the air is compressed so it warms up even more.”
The hot, humid air is “pumping” into the system from the Gulf of Mexico with “nothing to block it” as it travels inland, Phillips said.
“You’re breathing the same air at the end that you were at the beginning, it can become very stale, and it taxes even athletic people under these conditions.”
There will be little reprieve at night, either, Phillips said, which could be a greater health concern than the daytime highs.
As for our area, Environment and Climate Change Canada has issued a heat warning for Greater Sudbury, Markstay-Warren, St. Charles, West-Nipissing and French River as the hot, humid weather settles into the region.
The federal agency issues heat warnings when the forecast rises for two days to 29 degrees C or higher during the day and 18 C or higher at night or the humidex is 36 or higher.
Continuous exposure to high levels of heat can lead to dehydration and illnesses such as heat stroke, heat exhaustion, heat fainting, heat edema (swelling of hands, feet and ankles), heat rash, heat cramps (muscle cramps), and even death, Public Health Sudbury & Districts said in an advisory Thursday.
People who are most at risk include older adults, infants and young children, pregnant women, people with chronic illnesses, people who are homeless, people who use alcohol or illicit drugs, and those who work or exercise in the heat.
Those who take medications or have a health condition should consult their doctor or pharmacist to determine if they are at increased risk from the heat and follow their recommendations.
“Although some individuals are at higher risk, anyone can suffer from heat-related illnesses,” Burgess Hawkins, a manager with Public Health Sudbury & Districts’ Environmental Health Division, said in a release. “Everyone should take precautions.”
Environment and Climate Change Canada is predicting highs of 30 C for Friday and Saturday, before cooling Sunday with a high of 24 C.
Similar warnings have been issued for much of the province, including North Bay, Powassan, Mattawa and the Parry Sound area.
To prevent heat-related illness, the health unit recommends that you:
– Frequently visit neighbours, friends, and older family members, especially those who are chronically ill, to make sure that they are cool and hydrated.
– Drink plenty of cool liquids, especially water, before you feel thirsty to decrease your risk of dehydration. Thirst is not a good indicator of dehydration.
– Babies younger than six months of age do not need extra water in hot weather; however, you might need to feed them more often. Follow your baby’s feeding cues. Encourage babies older than six months and children to drink frequently. Offer the breast or if not breastfeeding, offer water.
– Reschedule or plan outdoor activities during cooler parts of the day.
– Wear loose-fitting, light-coloured clothing made of breathable fabric.
– Never leave people or pets in your care inside a parked vehicle or in direct sunlight—even if the windows are down.
– Take a break from the heat by spending a few hours in a cool place, for example, in a tree-shaded area, swimming facility, or an air-conditioned public building such as a shopping mall, grocery store, place of worship, public library, or home of a family member or friend.
– Take a cool bath or shower periodically, or cool down with cool, wet towels.
– Prepare meals that do not need to be cooked in your oven.
– Block sun out by closing awnings, curtains, or blinds during the day.
– Avoid sun exposure. Shade yourself by wearing a wide-brimmed, breathable hat or using an umbrella.
“Know the signs and symptoms of heat-related illness,” the health unit added. “They include dizziness or fainting, nausea or vomiting, headache, rapid breathing and heartbeat, extreme thirst, and decreased urination with unusually dark yellow urine.
“If you or someone in your care experiences these symptoms, contact a health care professional, friend, or family member for help. In emergencies, call 911.”
Public Health Sudbury & Districts offers information on beating the heat in apartment buildings, keeping your pets safe, doing outdoor activities in heat and smog, and keeping your children safe during hot weather.
Call 705-522-9200, ext. 464 (toll-free 1-866-522-9200) or visit phsd.ca for more information.