Madrid - A heatwave led Spain's national weather office on Wednesday to put seven provinces in the centre and south of the country on orange alert, the second-highest level of its four-alert scale.

Ciudad Real, Cordoba, Granada, Jaen, Madrid, Seville and Toledo will see temperatures soar to up to 40 degrees Celsius, national weather office Aemet said on its web site.

Despite the alert, the weather office stressed that temperatures were not unusual for this time of the year and were expected to drop slightly at the weekend.

An orange alert warns that weather conditions pose an "important risk" to human health.

Wildfires ravaged large amounts of forest and scrubland in Spain in 2005 and 2006 amid scorching temperatures but the country has so far this year escaped major fire damage due to a relatively wet spring which eased the effects of a drought in many parts of the country.