Fans, refreshing plants… The French are already preparing to face episodes of heat wave during the summer of 2023. Indeed, the previous summer was marked by long-lasting high heat and four episodes of heat wave. Moreover, the summer of 2022 is considered the second hottest since 1900. So what do meteorologists predict for this season?
“Contrary to last year, and while this first month of summer could rank second among the hottest months of June after 2003, France has not yet experienced a heat wave”, begins by explaining the editor of La Chaîne Météo. For good reason, we are not in the same weather situation as last year. But does this really mean that we are spared from scorching heat? What is the difference with the previous year?
“We remember that last summer was marked by puffs of hot air coming from North Africa and Spain”, recalls the editorial staff of the Weather Channel. Indeed, the depression off Portugal brought the air masses up from the South towards France by rotating movements. This scheme is more commonly referred to as the “heat pump” principle. Spreading from June to August, this phenomenon caused major forest fires in Aquitaine, following a severe drought. More so, it also had an impact on mortality in France.
On June 23, 2023, Public Health France published a report estimating the impact of heat on mortality in France during the summer. Between 1,000 and 7,000 deaths are attributable to the heat each year. “Apart from heat waves, hot temperatures, which are often perceived as not presenting a health challenge, nevertheless also lead to significant risks”, specifies the study. Thus, for the summer of 2022, there are 2,816 excess deaths. To avoid a similar situation, Météo-France and La Chaîne Météo are therefore already establishing a first forecast for this summer.
“The current month of June, the first month of the meteorological summer, is characterized by long lasting heat, and could moreover surpass, on average, that of last year which is, to date, the 2nd hottest recorded”, announces the editorial staff of the Weather Channel. But at the same time in 2022, France was already experiencing a first heat wave with temperatures above 40°C. This is not the case this year.
For the moment, the summer of 2023 depends on an anticyclone coming from northwestern Europe. The latter is responsible for the dry and hot weather in the northern half of France. On the contrary, the showers are more important in the south of France. This north/south divide was not as present in 2022. Meteorologists then predict weather conditions close to those of June 2023. But what are the expected temperatures for July and August?
Like the month of June, the summer could be marked by a north/south divide with dry weather in the northern regions of France and stormy showers in the south of the country. Indeed, “for the month of July, the high pressures could remain positioned in the vicinity of the British islands with the predominance of dry weather, while low pressures would bring a stormy tendency on the Mediterranean rim”, specifies the editorial staff of The Weather Channel.
Temperatures could then be 1.5 to 2°C higher than normal for the season. “In this context, the heat would be lasting and marked, but the storms should shorten the hot periods, limiting the risk of heat waves”, informs the editorial staff.
For the month of August, the most probable scenario would be a stabilization of temperatures with more frequent showers which would prevent the risk of a heat wave. Indeed, they “will act as an” anti-heat wave barrier “by shortening the episodes of strong heat before they degenerate into a heat wave”, ends up concluding the forecast site. Nevertheless, the margin of error of the forecasts does not make it possible to exclude a heat wave episode during the summer of 2023.