Lightning and thunderstorms​
Belgium 2024 review
Read our weather, climate and electrical analysis of thunderstorms in Belgium in 2024.
2024 at a glance
Joris Royet, Chef de projet Météo, METEORAGE
With almost 20,000 cloud-to-ground (CG) lightning strikes, 2024 was the fourth most lightning-struck year, in stark contrast to a very calm 2023.
Electrical activity was mainly concentrated in July, August and September.
- August was particularly active, accounting for more than a quarter of annual activity with 5,700 cloud-to-ground lightning flashes, due to a succession of storm fronts.
- July and September were also very active, in a context favourable to thunderstorm instability.
October marked a clear lull, with only a few cloud-to-ground lightning flashes detected. This trend continued in November and December, when instability was almost non-existent.
Joris Royet, Meteo Project Manager, METEORAGE.
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In 2024, our European Lightning Detection Network (ELDN) detected in Belgium
Key facts
The day most struck by lightning
13 August 2024
The month most struck by lightning
August 2024
The County most struck by lightning
Tournai
Focus on
Atypical thunderstorm sequence on 5 September
by Joris Royet, Weather Project Manager, METEORAGE.
Between the afternoon of September 5 and the following night, several intense thunderstorms swept across the regions in an unusual east-west flow.
The warm air was to the north and east of Belgium, while a cooler air mass occupied France. An area of low pressure between two anticyclones (over Scandinavia and the Atlantic) was reinforced by a cold drop aloft, blocked off the French coast.
An undulating front initially moved towards France before returning to the south of Belgium in the evening. The arrival of warm air from the east led to increasing instability as the afternoon progressed, with temperatures exceeding 25°C in the north-east of the country, as in Liège for example. A line of low-level convergence triggered the first thunderstorms over the Ardennes massif in the late afternoon.
Another sequence of thunderstorms set in during the evening, sweeping across the south-east of Belgium. These storms dumped up to 47.5 mm of rain in 24 hours at Tremelo (Flemish Brabant), causing local disturbances. Electrical activity is high under these systems, with some 5,000 cloud-to-ground lightning flashes detected in Belgium on 5 September.
Map of cloud-to-ground (CG) lightning flashes of 5 September 2024
On 5 September 2024, 3,098 CG flashes were detected, including :
+ positive CG flashes: 208,
– negative CG flashes: 2,890.
Belgium's lightning strike in 2024
For 2024, the cloud-to-ground lightning density (lightning strikes) for Belgium is 0.6413 cloud-to-ground lightning strikes per km².
Seasonality of thunderstorms
Seasonal distribution of cloud-to-ground lightning
The frequency, geographical distribution and intensity of thunderstorms vary with the seasons, depending on temperature, humidity and atmospheric dynamics.
In spring, thermal contrasts between cold and warm air set in and encourage the first convective thunderstorms, often accompanied by intense rain and sometimes hail or tornadoes, with electrical activity increasing as the season progresses.
In summer, they are more frequent and violent, fuelled by high temperatures and strong contrasts when cold drops pass through, generating thunderstorms that are sometimes supercellular, hence a peak in activity during this season.
Autumn sees a gradual reduction in electrical activity, but lows can still produce thunderstorms linked to transitions between air masses, particularly near waters that are still relatively warm.
In winter, although less frequent, thunderstorms can occur, often near the oceans or in regions where cold fronts meet warmer, more humid air.
Top 10 regions most struck by lightning
by number of cloud-to-ground (CG) lightning flashes​
by lightning density of cloud-to-ground (CG) lightning flashes per km²/year​
| 01. Walloon Region | 0.72 |
| 02. Brussels Region | 0.61 |
| 03. Flemish Region | 0.54 |
Top 10 Provinces most struck by lightning
by number of cloud-to-ground (CG) lightning flashes​
by lightning density of cloud-to-ground (CG) lightning flashes per km²/year​
| 01. Liège | 1.052 |
| 02. Antwerpen | 0.735 |
| 03. Luxembourg | 0.718 |
| 04. Vlaams Brabant | 0.715 |
| 05. Hainaut | 0.695 |
| 06. Limburg | 0.674 |
| 07. Brussel | 0.615 |
| 08. Namur | 0.484 |
| 09. Brabant Wallon | 0.450 |
| 10. Oost-Vlaanderen | 0.406 |
Top 10 des communes les plus foudroyées
by number of cloud-to-ground (CG) lightning flashes​
by lightning density of cloud-to-ground (CG) lightning flashes per km²/year​
| 01. Limbourg | 3.232 |
| 02. Rumes | 2.898 |
| 03. Theux | 2.643 |
| 04. Brunehaut | 2.444 |
| 05. Neupré | 2.332 |
| 06. Juprelle | 2.315 |
| 07. Modave | 2.230 |
| 08. Herstal | 2.170 |
| 09. Comblain-au-Pont | 2.121 |
| 10. Esneux | 2.079 |
The lightning strike on Belgium in recent years​
Since 2007, the cloud-to-ground lightning density (lightning strikes) for Belgium has been 0.2918 cloud-to-ground lightning strikes/km² per year.Â
The number of thunder days averages 45 per year.
Over the last 3 years​
Monthly distribution of lightning strikes​
Number of cloud-to-ground (CG) lightning flashes detected each month
Over the last 10 years​
Annual distribution of lightning strikes​
Number of cloud-to-ground (CG) lightning flashes detected each year
Annual distribution of thunder days
Number of thunder days detected annually
Terminology​
To help you better understand the information in this report, here are the definitions for some of the most frequently used terms.
Cloud-to-ground (CG) lightning flash​
Discharge of current of a certain intensity circulating between the cloud and the ground. Abbreviated to CG (Cloud-to-Ground).
Lightning density
The best current representation of thunderstorm activity is lightning density, which is the number of cloud-to-ground (CG) lightning flashes per km² per year.
Lightning flash​
All current discharges and electrical impulses from a lightning event. A lightning flash can occur within the same cloud (IC), between a cloud and the ground (CG) or between two clouds (CC). A lightning flash can be composed of one stroke or many strokes, which are current discharges and electrical impulses.
Thunder day​
Each day that lightning was detected in a given area.
About this lightning report​
The lightning report is based on data provided by METEORAGE’s lightning detection network (ELDN) in Europe.
The information we provide concerns cloud-to-ground (CG) lightning flashes and lightning density.
To be able to compare these data with the data collected, METEORAGE counts the main current pulse circulating between the cloud and the ground, defined in this report by the term “Cloud-to-ground (CG) lightning flash”.
Our expertise draws on more than ten years of analysis, observation and data collected in Europe, and more broadly worldwide. We have over 37 years’ expertise in France.
The performance of our network has been validated scientifically and delivers the best possible results with:
- > 98% lightning flash detection,
- a median detection accuracy of 100 meters,
- > 90% distinction made between cloud-to-ground (CG) lightning flashes and intra-cloud lightning flashes.
The METEORAGE network consists of more than 100 lightning sensors, calculators and a processing system that manages the databases. Our lightning sensors are based on the Vaisala technology, currently considered one of the best in the world. Our network achieves levels of performance validated by numerous scientific studies and publications.
This 2024 report is based on the most comprehensive source of information in Belgium. The data, densities, rankings and thunder days in this report are dated from 1 January 2024 to 31 December 2024.Â
