With record high temperatures seen in some areas over the last few days, the Ministry of Health has issued an advisory for people, urging them to drink water frequently and take measures against heatstroke. At the same time, the Fisheries Department has released an ‘extreme heat’ warning for fish farmers, urging them to be on the alert to prevent any losses arising from the soaring temperatures. The high temperature, which has persisted for weeks, poses a risk to aged people and children in the country. We are in the middle of the hottest period of the year. Heat waves are common in Myanmar during the months of March, April, and May, in the daytime as well as at night. With mercury levels rising to a record 41.5 degrees centigrade, the highest in 12 years, on 22 April in Pathein, there is a need to take precautions against heat waves. Extreme heat can lead to heatstroke and exhaustion, which can result in increased mortality rates. It can also exacerbate existing health conditions. Heat stress occurs when the body absorbs more heat than is tolerable. In southern Asia, mortality is likely to rise with the temperature. Researchers have established a direct link between global warming and deaths from killer heat waves. A slight increase of 0.5°C in mean summer temperatures in India, or another comparable tropical developing nation, could result in a 146-per-cent rise in the death toll. Heat in the summer months can be fatal. In 2016, the world experienced its hottest year since the 1880s, when modern records began to be kept. 2016 also marked the third consecutive year of record-high temperatures. Less than four months into 2017, parts of Myanmar, India, and Australia were already in the throes of heat waves. It is estimated that between 15,000 and 19,000 people died during the 2003 heat wave in France, while according to the United States’ Centers for Disease Control and Prevention (CDC), around 600 Americans have died every year from exposure to extreme heat between 1999 and 2010. Therefore, it is important that people pay attention to the daily weather forecasts released by the Meteorology and Hydrology Department. They must also be alerted about adverse weather conditions.