HANOI, March 23 (Xinhua) -- Major cities across Vietnam are being hit by the first summer heat wave of the year with levels of ultraviolet (UV) radiation soaring off the charts, Vietnam News Agency reported on Thursday.
According to experts, levels of UV radiation are forecast to hit up to 10.4 on a scale that level 10.5 and above is regarded as "extreme," with people cautioned to avoid exposure to the sun as just 15 minutes of unprotected exposure could burn human skin and eyes.
Vietnam's National Centre for Hydro-Meteorological Forecasting said the most dangerous levels of UV radiation hit between 10 a.m. and 1 p.m. local time, warning of very high risk of harm in the capital of Hanoi with UV Index levels rising to 9, Ha Long city in the northern province of Quang Ninh at 9.1, the central city of Da Nang hitting 9.9, Ho Chi Minh City, Can Tho city and Nha Trang city in the south-central Khanh Hoa province soaring up to 10.4.
UV levels are higher in southern Vietnam due to local weather conditions. They appear mostly during clear skies, in the middle of the dry season and in conjunction between dry and rainy seasons in southern Vietnam.
Doctors recommend people to consider not going out when the UV Index is above 7. If it reaches 10, the radiation can be extremely harmful, and people should stay inside to avoid direct exposure to sunlight.
State weather forecaster also warned of searing summer heat waves across the country, especially the central coastal cities of Da Nang and Quy Nhon, with temperatures in many parts of Vietnam expected to hover over 37 degrees Celsius.