The UN agency explained that an Atlantic low-pressure system between the Azores and Madeira is fuelling the warm front, pushing it towards western Europe.
10 degrees above normal
And although it’s only mid-June, temperatures in some parts of Spain and France, temperatures are - on average - more than 10 degrees Celsius (or 50 degrees Fahrenheit) higher than the average for this time of year.
In France, the heat spike follows the country’s warmest and driest May on record, and the country’s national weather agency said that it is the earliest heatwave since 1947.
In Spain, temperatures topped 40 degrees Celsius – 104 Fahrenheit - in parts of the country’s interior on consecutive days this week, and it’s been hotter still in Toledo province in recent days.
To make matters worse, Spaniards are also enduring a Saharan dust cloud, which has compounded health and environmental stress, WMO said, noting that Portugal recorded its warmest May since 1931.
In Switzerland, where maximum temperatures have been well above 30 degrees Celsius (86 Fahrenheit), the national weather service issued findings showing that the temperature difference between towns and the countryside, was as much as six degrees Celsius.
Drought warnings are an added concern in much of western Europe, as no significant rainfall is forecast in Europe in the coming days, apart from isolated thunderstorms.
Large areas from southeastern Central Europe to the northwestern Black Sea are also suffering from drought, WMO said, adding that in the US, much of the west of the country is facing its second or third drought year in a row, with fears of growing water stress heading into the summer season.
The two largest reservoirs in the US, Lake Mead and Lake Powell, in Arizona, are currently at the lowest levels since they were filled: both are at just below 30 per cent of capacity, according to the US Drought Monitor
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