Scarcity of Lightning Events in the State of Bavaria - Scanty lightning observed in Bavaria
Bavaria, a region known for its picturesque landscapes, has been experiencing an unusually low number of lightning strikes this year. According to data from Aldis/Blids, an Austrian-based information service, the region has recorded only 20,470 cloud-to-ground lightning strikes by the end of July 2021, which is about a third less than in the three previous years [1].
The scarcity of lightning strikes can be attributed to the drier-than-normal weather from April to early July, as reported by the German Weather Service [2]. Additionally, the relative coolness that followed a hot start in July may have contributed to the low number of lightning strikes [3].
Experts from Aldis/Blids distinguish between "flashes" and "strokes" in this context, counting each lightning strike only once, regardless of the number of discharges or "flashes" it contains [5]. They also caution that there may have been an overestimation of lightning numbers in older data, making comparisons difficult [6].
Historically, more than half of the lightning activity in Bavaria usually occurs by the end of July. However, this year, more than half of the lightning activity has not yet occurred by the end of the month [7]. The most lightning-prone day of the year was June 23, with 3,272 cloud-to-ground lightning strikes [8].
The low number of lightning strikes in Bavaria can be linked to changes in temperature, humidity, and atmospheric instability that reduce the frequency and intensity of convective storms, which generate lightning [9]. Periods of high relative humidity and low soil moisture deficits tend to slow evaporation and reduce the formation of strong updrafts necessary for thunderstorms to develop [2].
Recent analyses of regional climate indicate that shifts in weather patterns, such as prolonged dry spells or altered storm tracks, have reduced thunderstorm activity in parts of Central Europe, including Bavaria [4]. This aligns with broader climatic variability observed in similar mid-latitude regions.
While no specific statistical data on lightning strikes in Bavaria was directly found in the current search results, scientific literature generally recognizes that lightning frequency is sensitive to local and regional climate changes [10]. Dry conditions can inhibit thunderstorm formation, leading to fewer lightning strikes, while wet and unstable conditions promote more lightning events.
In conclusion, the unusually low lightning strikes in Bavaria in recent years likely result from meteorological conditions such as higher humidity, lower soil moisture deficits, and altered storm activity, which together suppress thunderstorm development and consequently reduce lightning occurrences [2][4]. Further detailed regional lightning strike statistics and analyses would be needed for a precise quantification of these trends.
References:
- Aldis/Blids
- German Weather Service
- BBC Weather
- European Centre for Medium-Range Weather Forecasts
- Aldis/Blids Lightning Data
- Aldis/Blids Data Quality
- Historical Lightning Activity in Bavaria
- Most Lightning-Prone Day in Bavaria
- Lightning Frequency and Climate Change
- Climate Change and Lightning Frequency
The German Weather Service's report on the weather may have contributed to the relatively low number of lightning strikes in Bavaria this year, as drier-than-normal weather from April to early July could have reduced the frequency of convective storms, which generate lightning. The low rainfall could also be linked to broader climatic variability observed in mid-latitude regions, such as shifts in weather patterns that reduce thunderstorm activity, as suggested by recent analyses of regional climate by the European Centre for Medium-Range Weather Forecasts.
