July 2019 European heat wave, GEOS model. Air temperature map of Europe, the Mediterranean and North Africa on 27 June 2019, colour-coded from 25 degrees Celsius (yellow) through 35 degrees Celsius (orange) to 45 degrees Celsius (red). Several countries in Europe saw record-breaking temperatures during this heatwave (which lasted into July), which was caused by a large area of high pressure (a heat dome) over the region. The resulting disruption of the jet stream drew hot air north from the Sahara Desert. An increase in the number and severity of regional heatwaves has been linked with global warming. This image was produced using data from the Goddard Earth Observing System-5 (GEOS-5) model.