The Kansas City area is looking at about three days of heat, and Wednesday’s expected air quality is poor enough that officials have posted an ozone alert.

The National Weather Service forecast for Wednesday is a high of 98, followed by possible highs of 99 Thursday and 95 Friday. The heat index could near 105, the point at which authorities begin issuing heat advisories as heat and humidity can quickly take a toll on human health. It cools off for the Labor Day weekend, with a high of 86 and a chance of thunderstorm Saturday. It’s setting up for a couple of perfect days Sunday and Labor Day: sunny with highs in the upper 70s.

In the meantime, however, it’s going to be hot. Today also is an orange alert day, the second highest on the Mid-America Regional Council’s four-color warnings in its daily “skycast” posted during the warm-weather months. That means there’s an elevated level of ozone at the ground level, usually formed by auto and power plant emissions, but lawnmowers are considered prime culprits, and the vapors that escape when fueling a vehicle react to sunlight to contribute to the problem, too.

On an orange alert day, the air is considered unhealthy for some groups of people, and those who are active or who have respiratory disease, such as asthma, should limit prolonged exertion outdoors. If you are going to be outdoors, try to limit activities to before 10 a.m. or after 7 p.m.

To limit the overall ozone problem, people are encouraged to drive less. The Kansas City Area Transit Authority cuts its fares in half on orange and red alert days. Also, postpone mowing the lawn. Skip filling up the car for a day, or fill up after sundown.

National Weather Service: www.weather.gov/kc

More on ozone alerts: www.marc.org/airQ