The current heat wave becomes the second longest ever recorded in France

If the episode of extreme heat seems endless to you, that's normal. The current heat wave is already the second longest ever recorded in France, Météo-France announced on Wednesday August 19. “With a definitive ITN [national thermal indicator] at 24.5°C for the day of Tuesday August 18, we are 22 days into a heat wave, 2nd provisional rank since 1947”, the start date of the measurements, the national forecaster informed AFP.

This wave exceeds in duration that of July 2006 and its 21 days. It already surpassed that of 2003, Météo-France reported. The record for the longest heat wave remains held by the summer of 1983, during which France was suffocated for 23 days.

More than 50 days of heat wave in 2026

Since Tuesday, there is also no longer any department concerned by an orange "heat wave" vigilance in the country, after its lifting in six departments in the South-East. But the heat wave, which began on July 28, with two peaks of intensity marked on July 29 and then from August 12 to 14, is still not over. Because Météo-France distinguishes between heat waves and heat waves.

This second phenomenon begins when the ITN reaches or exceeds 25.3°C for one day and the national average temperature remains greater than or equal to 23.4°C for at least three consecutive days. It ends when the ITN drops below 23.4°C for at least three days in a row, or “occasionally” below 22.4°C. The heat wave differs from heatwave alerts, whether yellow, orange or red, established according to the intensity of the expected weather phenomena and its possible health impacts.

In terms of intensity, that is to say concerning the level of maximum temperatures reached, the heat wave at the end of June 2026 remains the strongest ever experienced in France. On the other hand, if we talk about the most severe heat wave, a criterion combining both the length and the intensity of the wave, August 2003 remains the record.

Another figure is dizzying: mainland France has experienced 52 days of heat waves since mid-June, a record even though the summer is not over, ahead of the 33 days in 2022 or the 22 days of the deadly summer of 2003, according to AFP's analysis of Météo-France data. Since June 17, only three, then eight days of calm have intervened between these scorching temperatures.