A heat wave that never ends. For almost a week, France has been experiencing extreme temperatures for the season, with monthly records broken from Brittany to the South-West. The mercury is particularly panicking this Thursday, May 28, which could become the hottest May day ever observed since data has been recorded.
Since the dawn of time, people have been interested in the weather. During Antiquity and the Middle Ages, the observation of the weather oscillated between scientific and divine explanations. Popular sayings relating to the weather are multiplying, as evidenced in 1491 by the Shepherds’ Calendar almanac. Fifty years later, Le Miroir du temps by Antoine Mizauld is the first work to invite, in French, to observe nature to predict climate change.
However, it was not until the 17th century that scientific meteorology was born, with the development of the thermometer and the siphon barometer. In the 1770s, the Royal Society of Medicine of France launched a vast investigation, involving around 150 doctors and pharmacists across the territory, as well as in Italy, Austria, Germany, the United States and Madagascar. Pressure, temperature, sky conditions, precipitation, wind and humidity… The monthly averages recorded are thus standardized and published in the institution’s History and Memoirs magazine.
The telegraph, an ally of forecasts
From the second half of the 18th to the 19th century, the exploration of the atmosphere developed thanks to hot air balloons. In 1855, the first French network of meteorological stations dedicated to weather forecasting was created. Precipitation and minimum and maximum temperature readings are taken there once a day.
The same year, Urbain Le Verrier, French astronomer and mathematician, highlighted the role of a new invention, the telegraph, in weather forecasting. He thus demonstrated to Napoleon III that the existence of a telegraphic meteorological network would have enabled him to avoid the loss of a large part of the French fleet during the storm off the coast of Sevastopol. The following year, an international meteorological service with telegraphic transmission was established, to warn sailors of the arrival of storms.
In September 1863, the meteorological bulletin of the Paris Observatory was published for the first time, an innovation in Europe. Out of caution, he prefers to provide an “advice for the next day” and communicates probabilities, rather than using the word “forecasts”. In 1878, the Central Meteorological Bureau, ancestor of Météo France, opened its doors on rue de l’Université in Paris.
Sending a weather satellite into space
The two world conflicts and the development of aviation allowed major advances in the field. In 1948, a French automatic station was tested in Trappes (Yvelines). The first weather radar was installed there a year later.
In the 1960s, a meteorological satellite was sent into space, marking a turning point in the history of meteorology. At the same time, a center dedicated to the collection and processing of spatial data for meteorological purposes was opened in Lannion. An experimental network of automatic stations was later set up in mainland France as well as on certain overseas sites.
In 1996, Météo France launched the Radome project, a reorganization of its ground observation network. In 2001, a new meteorological vigilance procedure came into force in the event of a dangerous meteorological phenomenon. Since 2004, it covers heatwaves and severe cold weather. Since 2017, Météo France has also asked citizens to share real-time information on the weather where they are, in order to complement conventional networks.
