As Chicago Public School students prepare to head back to class on Monday, they will be greeted by scorching temperatures as the heat index is expected to break 100 degrees. The National Weather Service in Chicago has issued an excessive heat warning from Monday afternoon to Tuesday evening, cautioning residents about the dangerously hot and humid conditions.

To combat the intense heat wave, the city of Chicago has taken several measures. Cooling centers have been opened throughout the city, and residents are strongly encouraged to stay indoors as much as possible. In anticipation of the high temperatures, Chicago Public Schools has canceled all outdoor activities or moved them indoors. The school district has also reassured parents that all classrooms are equipped with air conditioning and will be maintained at comfortable levels. In the event of any cooling system malfunctions, procedures are in place to address the issue promptly.

While Chicago Public Schools assures the community of their preparedness, the Chicago Teachers Union (CTU) has expressed concerns regarding the older school buildings that lack proper cooling systems. The teachers' union has been negotiating with CPS for improved cooling infrastructure but is disappointed that the matter remains unresolved before the start of the school year. However, CTU remains confident that CPS will effectively handle the extreme heat wave this week.

Meteorologists have warned that heat index values could reach 107 degrees on Monday and 110 degrees on Tuesday. Additionally, overnight temperatures are expected to remain high, only dropping to the mid- to upper 70s. The Illinois Environmental Protection Agency declared an Air Pollution Action Day for Chicago-area counties on Sunday and Monday due to elevated ozone levels caused by pollutants from vehicles, industrial sources, and ongoing wildfires, such as those in Canada.

The combination of extreme heat and poor air quality is not uncommon as stagnant hot air tends to trap particulate matter. Climate change is exacerbating the situation, making the Chicago area more humid and increasing the "feels like" temperature or heat index. Over the past six decades, average summer temperatures have risen by 1.5 degrees, while average lows have increased by 2.2 degrees. These rising temperatures pose health risks as the body does not have adequate time to cool down during warm nights following hot days.

It is important to note that the impact of hot weather is not equally felt across all areas of Chicago. Dense residential and industrial areas tend to retain heat more than neighborhoods near open spaces like the lakefront, leading to significant temperature differentials within the city.

Sunday and Monday's air quality has been deemed unhealthy for sensitive groups, including individuals with asthma, children, and older adults. The Illinois Environmental Protection Agency advises these individuals to limit outdoor activities.

As the heat wave continues, the National Weather Service and the city of Chicago are urging residents to stay hydrated and seek air-conditioned spaces. They also emphasize the importance of never leaving children or pets unattended in vehicles, as temperatures inside can quickly become lethal.

Despite limitations on outdoor activities at schools, parents are advised to dress their children in loose-fitting clothing and provide them with full water bottles before sending them to school.

Relief from the scorching temperatures is expected in the form of scattered thunderstorms on Tuesday afternoon and evening, which will provide some respite for the city. Some of these storms may be severe, with damaging winds and isolated hail.

As Chicagoans navigate through this heat wave, it is crucial to stay informed, take necessary precautions, and prioritize safety, particularly for the most vulnerable members of the community.

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