Union City, New Jersey is under an extreme UV Index alert due to high levels of ultraviolet (UV) radiation, which poses significant health risks. The UV index, measuring the strength of sunburn-producing UV radiation, has reached alarming levels, requiring immediate attention and protective actions. High UV exposure can lead to sunburn, premature skin aging, eye damage (like cataracts), and an increased risk of skin cancer. Residents are advised to take precautions, especially during peak sunlight hours between 10 a.m. and 4 p.m.