Why are heat waves dangerous?

<p style=";text-align:left;direction:ltr">Arab Weather - The danger of heat waves lies in their direct impact on human health, especially when they coincide with high humidity levels. When humidity increases, temperatures become more severe and impactful.</p><p style=";text-align:left;direction:ltr"> This effect is explained by combining air temperature with relative humidity to determine the &quot;perceived temperature&quot; or actual feeling of heat. For example, a weather service may report a temperature of 38°C, but the actual feeling may be 42°C, due to the effect of humidity. According to this index:</p><ol style=";text-align:left;direction:ltr"><li style=";text-align:left;direction:ltr"> 27 to 32 degrees Celsius: Indicates the need for moderate caution, as a person can be harmed if exposed to the sun for long periods.</li><li style=";text-align:left;direction:ltr"> 32 to 41°C: Extreme caution is required, as this can lead to the risk of heat stress.</li><li style=";text-align:left;direction:ltr"> Heat stress is a condition in which the body&#39;s inability to adapt to high temperatures impairs its ability to cool itself. Symptoms begin with thirst and dehydration, and may progress to heat shock, which includes severe headache, loss of concentration, and skin inflammation.</li></ol>