The extreme heat poses a significant risk to residents in the Santa Ana Mountains and surrounding foothills. Prolonged exposure to high temperatures can lead to heat-related illnesses such as heat exhaustion and heat stroke. Vulnerable populations, including the elderly, children, and those with pre-existing health conditions, are particularly at risk. Outdoor workers and individuals engaging in physical activities outdoors should exercise caution. The warm nighttime temperatures may also limit recovery from daytime heat, increasing overall health risks.