The expected intensity and duration of high heat and humidity this week could take a toll on the health of residents of the metro area.

Already the combination of heat and light wind is causing problems with ground-level ozone, prompting an ozone alert for the metro area for a second straight day today. The Mid-America Regional Council SkyCast for today is orange – the third highest on a four-step scale – meaning those with breathing issues such as asthma should take care and avoid overexertion outdoors.

Overall, residents are advised to limit driving and the use of other internal-combustion machines such as lawnmowers, and fill up their vehicles after dark. Local bus fares are reduced to 75 cents on ozone-alert days.

National Weather Service on Monday replaced the excessive heat watch that was to have begun today with an excessive heat warning that runs from noon Wednesday to 8 p.m. Saturday.

Overnight lows are only going to be in the upper 70s, so for those without air-conditioning the body has less a chance of recover from the day’s intense heat.

Residents are advised to dress in light and loose-fitting clothing, drink plenty of fluids, stay in the shade or, better yet, in air-conditioned spaces for extended periods. If possible, put off strenuous outdoor work.

 

Forecast

• Today, sunny and 94. Heat index up to 100. Light south wind. Overnight low of 74.

• Wednesday, sunny and 95. Heat index near 103. Light southerly breeze. Low of 76.

• Thursday, sunny and 98. Overnight low of 78.

• Friday, sunny and 99, followed by a low of 79.

• Sunny and hot Saturday, with a high near 98. Low around 76.

• Slight break Sunday, with a high of 94. Chance of rain. Low of 71.

 

Air quality

The Mid-America Regional Council posts a daily SkyCast, predicting ozone conditions. Ozone is created at ground level when fumes such as car exhaust or gas fumes mix with sunlight. That’s usually the worst on hot, calm days. Ground-level ozone can contribute to breathing problems.

MARC posts four levels of air quality: green, yellow (which means some concerns and a suggestion that those especially sensitive to breathing issues limit their outdoor activity), an orange alert and a red alert. Orange alerts generally happen several times each summer.

On alert days, MARC suggests two courses of action: Take care of yourself, and take steps to limit pollution.

To protect your own health, reduce strenuous outdoor activities or do them before 10 a.m. or after 7 p.m. Ozone can affect breathing and can cause wheezing and coughing. It also can more noticeably affect those with health problems. Keep your medicine for breathing or heart problems close at hand.

To cut down on pollution, drive less. Take the bus, take a bike or carpool. Avoid mowing until the SkyCast returns to green. MARC says a gas-powered mower in one hour can spew as much pollution as a newer car going 140 miles. Also, avoid refueling during ozone alerts, or at least wait until 7 p.m.

 

Tips to be safe

Heat-related illnesses happen every summer. To be safe, take it easy and drink plenty of non-alcoholic fluids.

Some suggestions:

• Spend at least some time each day in an air-conditioned space.

• Wear lightweight, loose-fitting and light-colored clothing.

• Limit outdoor activity to the morning and evening, when the heat is less intense.

• Don’t leave anyone – including pets and especially small children – in a locked vehicle, even for a minute.

• Make sure outdoor pets have access shade and plenty of fresh water. The Humane Society of Missouri suggests keeping pets indoors if you can.

• Plenty of good old water is a good choice for staying hydrated. Alcohol, sugary drinks and even caffeinated drinks such as coffee are less than ideal. Sport drinks, though many are high in sugar, can be a good option, and the U.S. Department of Health and Human Services suggests a mix of one part “sport electrolyte drink” to two parts water.

 

Know the symptoms

The Weather Service points to three progressively worse heat-related health problems:

• Heat cramps are often accompanied by heavy perspiration. Apply firm pressure to cramped muscles, massage any muscles that are in spasm, and sip water unless you become nauseated.

• Heat exhaustion has a variety of symptoms: weakness; fainting; dizziness; heavy perspiration; cool, pale or clammy skin; muscle cramps; nausea or vomiting; and a fast but weak pulse. Move that person to a cooler place. Have him lie down, and loosen some clothing. Offer sips of water, and apply cool, wet cloths to as much of the body as possible. Use a fan, or, better yet, get to an air-conditioned space. If the person vomits more than once, get medical attention right away.

• The worst is heat stroke. It’s an emergency and can be fatal. The person can slip into an altered mental state and can have a throbbing headache, nausea, dizziness, shallow breathing and confusion. The skin can be hot, red, dry or moist, and the pulse can be strong and rapid. The body temperature can rise above 103, and the person can faint.

Call 911 or get the person to a hospital. Don’t give fluids. Get to a cooler environment, preferably one that’s air-conditioned. Use cool cloths or a bath to reduce the body temperature. Use a fan if the heat index is below the high 90s, but remember that a fan can make you hotter at high temperatures.