In early August 2017 Southern Europe experienced a severe heat wave that the media referred to as ‘Lucifer’: in many parts of Southern Europe air temperatures exceeded 40°C.

In Slovenia this was the fourth heat wave in recorded history with air temperatures above 40°C (three of them occurred in the last 15 years). For Lucifer, the LSA SAF land surface temperature product (LSA-001) proved to be particularly well suited to monitor ground conditions and to locate the hottest areas. Although satellite-retrieved land surface temperature (LST) is not identical to air temperature measured 2 meters above ground, the areas where both quantities reach their maximum are usually identical.

The animation shows daytime LSA SAF LST for 3 - 4 Aug 2017 in 30-minute intervals over Slovenia. There is no information over cloud-contaminated regions (shown in white), which is important for maximum temperature interpretation by forecasters. Additionally, observations of maximum daily air temperatures in degree Celsius are superimposed on the animation.