Authorities imposed speed limits on some autobahns due to concerns the high heat would cause expressway surfaces to buckle. Some French schools stayed closed as a precaution due to worrying hot weather.
German weather agency Deutscher Wetterdienst said a preliminary reading showed the mercury reached 38.6 degrees Celsius (101.5 F) in Coschen, near the Polish border. That's a tenth of a degree higher than the previous national record for June, set in 1947 in southwestern Germany.
The Czech Hydro-Meteorological Institute said the temperature reached 38.5 Celsius (101.3 F) in Doksany — a Czech Republic high for the month. New daily records were set at some 80% of local measuring stations.
And it's about to get even hotter. Authorities have warned that temperatures could top 40 degrees Celsius (104 F) in parts of continental Europe in the coming days as a plume of dry, hot air moves north from Africa.
The transport ministry in Germany's eastern Saxony-Anhalt state said it has imposed speed limits of 100 kph or 120 kph (62 mph or 75 mph) on several short stretches of highway until further notice. (same as autobahn above?)
Those stretches usually don't have speed limits, but officials worry they could crack in the heat and endanger drivers. Professor Hannah Cloke, a natural hazards researcher at Britain's University of Reading, said the heat along with a build-up of humidity was a "potentially lethal combination."
"Children, the elderly and people with underlying health conditions are particularly at risk," she said. Precautionary measures also were taken in France, where temperatures up to 39 degrees Celsius (102 Fahrenheit) are forecast for the Paris area later in the week.
Similarly baking conditions are expected in much of the country, from the Pyrenees in the southwest to the German border in the northeast. Because such high temperatures are rare in France, most homes and many buildings do not have air conditioning.
In Paris on Wednesday authorities banned older cars from the city for the day as the heat aggravates pollution problems. Regional authorities estimated the measure, targeting vehicles including gasoline cars from 2005 or older and diesel cars from 2010 or older, affects nearly 60% of vehicles circulating in the Paris region. Violators face fines.
French charities and local officials were providing extra help for the elderly, the homeless and the sick this week, remembering that some 15,000 people, many of them elderly, died in France during a 2003 heat wave.
Prime Minister Edouard Philippe cited the heat wave as evidence of climate destabilization and vowed to step up the government's fight against climate change. The scorching heat was felt on the streets of Vienna, too.
"We're slightly below 35 degrees (Celsius) right now," said Wolfgang Fasching, driver of one of the city's traditional horse-drawn carriages. "At 35 degrees we go home because then the horses in Vienna get time off due to excessive heat."
With temperatures in Milan forecast to hit 40 C, an aid group said it was preparing to distribute 10,000 bottles of free water to the homeless and other needy people. The Civil Protection service in Rome also planned to distribute water to people at risk during the hottest hours of the day.
About half of Spain's provinces are on alert for high temperatures, which are expected to rise as the weekend approaches. The northeastern city of Zaragoza was forecast to be the hottest on Wednesday at 39 C, building to 44 C on Saturday, according to the government weather agency AEMET.
Some tourists sought relief in Madrid's green spaces. "It is pretty hot right now, we are dealing with it by trying to stay in the shade here in the park," said Victoria Poliak from San Diego, California.