Hot weather and air quality alert to highlight Fourth of July weekend

70 million people are at risk from severe heat waves. Another 100 million could be affected by smoke from the fires in Canada.

Fourth of July weekend marks the beginning of summer in much of the nation. This year, the weather could affect Americans wishing to travel.

One-hundred million people could be affected by the poor air conditions resulting from the smoke coming from the fires in Canada, which already affect 20 states. On Wednesday, it reached Iowa, western Pennsylvania, North Carolina and Washington, D.C. A day later, air conditions worsened in Minneapolis, Chicago, Indianapolis, Atlanta, Pittsburgh, Detroit and New York. Smoke also reached Pennsylvania and southern New Jersey. However, the poor air quality could dissipate slightly on Friday as showers and thunderstorms hit the region.

These rains and thunderstorms are a consequence of the second weather phenomenon facing the nation: heat waves. The high temperatures could harm more than 70 million people. In addition, these have been accompanied by thunderstorms that have caused most of the delays and cancelations in the country's airports.

The heat wave, with temperatures as high as 104 degrees Fahrenheit, began in Mexico, where it caused the death of at least 112 people. It then moved to the United States where it caused the death of at least thirteen people in Texas.

The weather situation also affected states such as Oklahoma and New Mexico and is expected to worsen as the weekend progresses. This was stated by the National Weather Service, which issued the following warning: