Weather experts in Portugal have revealed exactly when they believe a plume of heat from Africa will arrive in the UK.
The Portuguese Institute for Sea and Atmosphere has predicted when the next 'heat wave' will reach the UK.
In the next seven days hot weather is set to hit Portugal, bring temperatures of 35C to 40C by Friday, August 13.
Forecasters say it will then spread north, reaching the UK by August 20.
According to Portuguese newspaper Correio da Manha the forecasters say "The heat wave raises the alert in Northern Europe towards the possibility of temperatures exceeding 30C from August 20 in the United Kingdom and also in Norway. "
It is a possibility that heat records will be broken as the hot weather spreads across northern Europe - including France and Germany.
Experts say the hot weather will remain for the remainder of August.
The Met Office says it cannot yet forecast a heat wave for the end of August, but its long-term forecast for August 21 to September 4 reads: "Temperatures are likely to be above average, with the potential for hotter weather later in the month."
But the UK forecasters also say that before this there will be heavy showers and strong winds.
