Lightning and thunderstorms
Portugal 2024 review
Read our weather, climate and electrical analysis of thunderstorms in Portugal in 2024.
2024 at a glance
Joris Royet, Chef de projet Météo, METEORAGE
With more than 24,000 cloud-to-ground (CG) lightning strikes detected, 2024 was the fifth year with the most lightning activity in Portugal since METEORAGE records began. This electrical activity was mainly concentrated in the month of June, which recorded more than half of the year’s detections. Cold drops, localised off the coast or directly over the country, were the main triggers for the worsening of storm episodes. The month of June 2024 thus stands out as the fourth June with the highest lightning activity in the country’s recorded history.
However, storm activity varied considerably throughout the year. While June was particularly active, August saw a virtual absence of thunderstorm episodes, with only 70 cloud-to-ground lightning strikes recorded. This stability can be explained by the high position of the anticyclonic belt, which favours hot, dry conditions in southern Europe. After this period of summer calm, activity increased again in October and November, associated with more extensive disturbed systems extending as far as North Africa.
In general, electrical activity in Portugal in 2024 followed an irregular pattern, mainly influenced by the presence of cold drops. The relatively mild waters of the Atlantic Ocean played a key role in fuelling storm episodes, particularly during the winter and autumn seasons.
Joris Royet, Weather Project Manager, METEORAGE.
Our European Lightning Detection Network (ELDN) detected in Portugal, in 2024
Key facts
The day most struck by lightning
29 July 2024
The month most struck by lightning
June 2024
The town most struck by lightning
Bragança
Focus on
Thunderstorm episodes crossing the country on 29 July 2024
by Joris Royet, Weather Project Manager, METEORAGE.
Under the influence of an isolated cold drop positioned over the near Atlantic, a marked instability developed over south-west Europe, affecting Portugal and Spain in particular. At the same time, France saw the advance of a dry and very warm southerly flow. This meteorological context favoured the appearance of several waves of thunderstorms that spread from south to north, fuelled by a strong thermal contrast.
While temperatures often reached 35°C to 40°C in the interior of Spain and Portugal, cold air from the south-west amplified the convective dynamics.
This episode was marked by two distinct waves of storms.
The first affected southern Portugal in the morning with fairly weak intensity, while the second, linked to convergence at low levels, developed in the north in the evening after a particularly hot day.
These nocturnal storm episodes gradually strengthened and migrated towards the Atlantic, increasing in intensity.
In total, almost 3,000 cloud-to-ground (CG) lightning strikes were recorded during this rainfall event, with electrical activity evenly distributed throughout the country.
Lightning activity (CG cloud-to-ground lightning) on 29 July 2024
Lightning strikes in Portugal in 2024
For 2024, the density of CG cloud-to-ground lightning for Portugal is 0.2716 CG cloud-to-ground lightning per km².
Seasonality of thunderstorms
Seasonal distribution of CG cloud-to-ground lightning flashes
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 districts 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. COIMBRA | 0.513 |
| 02. CASTELO BRANCO | 0.401 |
| 03. VIANA DO CASTELO | 0.356 |
| 04. GUARDA | 0.342 |
| 05. BRAGANÇA | 0.311 |
| 06. FARO | 0.286 |
| 07. LEIRA | 0.283 |
| 08. SANTARÉM | 0.281 |
| 09. BEJA | 0.250 |
| 10. VISEU | 0.248 |
Top 10 municipalities 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. PAMPILHOSA DA SERRA | 1.279 |
| 02. ARGANIL | 0.968 |
| 03. GÓIS | 0.887 |
| 04. SEIA | 0.725 |
| 05. OLEIROS | 0.716 |
| 06. OLIVEIRA DO HOSPITAL | 0.709 |
| 07. VILA REAL DE SANTO ANTÓNIO | 0.702 |
| 08. ENTRONCAMENTO | 0.656 |
| 09. PEDRÓGÃO GRANDE | 0.651 |
| 10. CASTANHEIRA DE PÊRA | 0.638 |
The lightning strike in Portugal in recent years
Since 2007, the lightning strike density for Portugal has been 0.0933 cloud-to-ground (CG) lightning strikes per square kilometre per year.
The average number of storm days is 42 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 strike activities in Portugal
Number of cloud-to-ground (CG) lightning strikes detected annually.
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 Portugal. The data, densities, rankings and thunder days in this report are dated from 1 January 2024 to 31 December 2024.
