Heat

Hottest day in Sydney since 1939

Temperatures reached 47.3°C in Penrith, Sydney on Sunday 7th January – the hottest temperature in the region in 79 years, when the mercury previously reached 47.8°C.

Severe fire warnings were issued for the greater Sydney area and thousands of properties across New South Wales were left without electricity, partly because of the heat. England's batsmen also struggled on the hottest day on what was also record heat for a Test match in Australia.

World Weather Review: June 2017

In Arizona, USA, an ongoing heat wave has seen some of the highest temperatures ever recorded. Temperatures in Death Valley reached 54°C and flights to Phoenix were cancelled when airport temperatures reached 48°C. The heat wave has led to wild fires.

High temperatures across southern Europe have also caused problems – Portugal and Spain in particular have been tackling forest fires to which they were vulnerable after a dry winter and spring.

Heat Stress

Heat stress occurs when the body’s means of controlling its internal temperature starts to fail. Some cultures have adapted to avoid heat stress – the Mediterranean siesta signals a work break during the hottest part of the day, or in the tropics where work begins earlier, ends later and is carried out at a slower pace. Heat stress is not something we experience very often in the UK, especially after recent summers, but if we do experience a heatwave – a prolonged spell when daytime and overnight temperatures are elevated and humidity is high - we need to be prepared.