Temperatures soared above 40 degrees (104 degrees Fahrenheit) in Spain and Portugal on Monday prompting health concerns and the scorching heat was expected to move north to France and Britain later in the week.

The soaring temperatures prompted Spain's national weather office to put the region of Cordoba on red alert, the highest level on the scale, meaning the weather posed an "extreme risk" to health.

Temperatures in the countryside of Cordoba, a region of whitewashed houses in Andalusia, were expected to climb to 44 degrees Celsius.

Spaniards flocked to the beach with officials urging them to avoid alcohol and consume plenty of water as 43 of the country's 50 provinces were on orange alert -- the second highest warning -- due to the heatwave.

The cities of Castelo Branco and Portalegre in Portugal's interior also sizzled with temperatures hitting 41 degrees Celsius.

France is meanwhile bracing for the thermometer to hit 39 degrees Celsius by the middle of the week, while Britain will have to contend with temperatures in the mid-30s.

"These are not usual meteorological phenomena, (they are) of an exceptional intensity and with a very high level of risk for the population," a spokesman for Spain's national weather office said.

In the Andalusian capital of Seville, where temperatures shot up to 42 degrees Celsius, children and adults soaked their feet in city fountains for relief from the heat while others jumped from bridges into the Guadalquivir river.

Beaches across Spain's southern coast were packed as the heatwave coincided with the start of the high season for tourism.

Authorities in Spain and Portugal warned that the scorching temperatures posed a high risk of forest fires.

Nearly all of Spain faced an "extreme", "very high" or high" risk of forest blazes on Monday, according to the nation's weather office.

Madrid city hall was advising everyone to remain hydrated throughout the day by drinking at least three litres of water per day and avoid drinking alcohol.

The expected jump in temperatures in Britain prompted one newspaper to breathlessly predict that the nation would be sweating in 36 degrees Celsius heat on Wednesday.

If the mercury goes that high it would be the hottest ever recorded at the Wimbledon tennis championships which got underway Monday in south London.

The forecast has prompted concern in France where a European-wide heatwave in 2003 led to nearly 20,000 deaths above the normal rate, mainly among elderly people.

France has already called on air-conditioned public spaces to allow the public in for respite from the heat.

"I don't think this heatwave will have the same consequences as the one in 2003 because we weren't as prepared at that time," said Ecology Minister Segolene Royal.

The fiery temperatures are expected to last through the end of the week.