Intense rainfall with minimal thunderstorms, substantially reduced lightning occurrence
In the summer months of 2025, Germany experienced a significant decrease in lightning strikes, marking a historic low compared to the past 15 years. From June 1 to July 31, only about 394,000 lightning strikes were detected, according to data from the German Weather Service [1].
This phenomenon appears to be linked to a "summer monsoon"-like weather situation, where a stationary disturbance over Germany caused continuous heavy rainfall and fewer thunderstorm events that typically generate lightning [3]. While the weather included frequent rainfall and cooler conditions interrupting sunny days, the thunderstorms that did occur were concentrated in southern regions, limiting overall lightning activity across the country [3].
Meteorologist Nikolas Zimmermann from the weather service UBIMET stated that this summer has had fewer large-scale thunderstorm systems generating many lightning strikes in Germany's latitudes [4]. Each lightning strike is counted only once, even if it has multiple discharges and flickers [5].
Climate variability and stationary weather disturbances played important roles in suppressing typical lightning-generating thunderstorms [3][2]. While the exact reasons for this unusual weather pattern are not yet fully understood, climate factors such as the complex interactions of air pollution, convection, and cloud physics might also influence lightning patterns [2].
Despite the low number of lightning strikes this summer, the thunderstorm season in Germany usually lasts from May to August. Interestingly, the German Weather Service reported an average of 114 liters of rain per square meter in July 2021, indicating that the country has experienced considerable rainfall during the summer months [6].
Despite the low lightning activity this summer, the total number of lightning strikes recorded by Aldis/Blids in July 2021 was 23,986, which is a decrease of approximately 43% compared to the same month in 2020 (41,129) [7]. As of now, the total number of lightning strikes recorded by Nowcast for the year 2025 stands at 563,000, indicating that the current year is on track to potentially surpass the previous record of 813,000 from 2020 [8].
In conclusion, the 2025 summer experienced frequent rain and storm disturbances that limited thunderstorm activity producing lightning strikes in Germany [1][3]. This resulted in a historic low number of lightning strikes compared to the previous 15 years [1]. Climate variability and stationary weather disturbances played important roles in suppressing typical lightning-generating thunderstorms [3][2]. The thunderstorm season in Germany usually lasts from May to August, and while the current year has seen relatively few lightning strikes, it remains to be seen whether the total number for the year will surpass the record set in 2020.
[1] German Weather Service (DWD) data [2] National Oceanic and Atmospheric Administration (NOAA) [3] European Centre for Medium-Range Weather Forecasts (ECMWF) [4] UBIMET meteorologist Nikolas Zimmermann [5] Aldis/Blids only counts ground lightning, not discharges between clouds [6] German Weather Service report on July 2021 rainfall [7] Aldis/Blids data on total lightning strikes in July 2021 and 2020 [8] Nowcast data on total lightning strikes in 2025 so far
Weather-forecasting models for the following summer months could potentially help anticipate similar weather patterns, as climate variability and stationary weather disturbances played a significant role in suppressing lightning-generating thunderstorms in the summer of 2025 [2]. By understanding the complex interactions of air pollution, convection, and cloud physics, weather-forecasting teams might be able to predict future counterparts of the "summer monsoon"-like weather situation [2].
