The heavy rainfall storm that affected Catalonia on October 3rd and 4th could have been much more than an episode of strong storms. An analysis published on the official blog of the State Meteorological Agency (Aemet) points out that the powerful mesoscale convective system that developed off the Catalan coast showed signs compatible with an attempted formation of a tropical cyclone, a process that "had not been documented until now in the Mediterranean," as highlighted in the same work. In fact, the storm forecasts already indicated the possibility of the formation of a medicane —a Mediterranean mini-hurricane—, although it ultimately did not happen.

"I woke up because it was raining so hard that water was entering our house through the windows, to the point that an inch of water had accumulated in the dining room. And I'm talking about a third floor." Sergi Morell, a resident of Oliva, will not easily forget the DANAAdam, which has left historic records in the Valencian regions of La Safor and La Marina Alta: up to 720 liters per square meter in nearly 36 hours. The episode also caused rivers to overflow, flooded six municipalities, and left hundreds of people trapped in their homes. A count to which the most tragic of balances must be added: as of now, there are three fatalities, a woman and a man from Oliva and another from Sagunto, who had disappeared on Sunday afternoon at the beach where she had been swimming, even though an orange alert for rain and coastal phenomena had been active all day.

After many days of calm and weather that is too warm for the time of year, the weather will become complicated this weekend. The anticyclone will move to northern Europe and, at the same time, a storm will form in the Mediterranean. All this will open the doors to the arrival of a pocket of cold air at high altitude coming from central Europe towards the Iberian Peninsula, as well as humid and warm maritime winds towards the Catalan coast. This will clearly increase instability, with the return of rain and a sudden, full autumn atmosphere. The sea water remains warmer than it should be, which can cause the rainfall to be more intense, just as it has been in recent weeks.

Raymond T. Pierrehumbert (United States, 1954) studies the most extreme climates in the Universe, those of distant planets where it rains glass or that of gaseous worlds where the daytime temperature is so high that the molecules of the atmosphere break down into atoms. Also that of Earth, both the current one and the one from 4.5 billion years ago. This perspective allows him to put into context to what extent the pale blue dot on which we are lucky to live is exceptional – and at the same time fragile. Professor of planetary physics at the University of Oxford and the Massachusetts Institute of Technology (MIT), he is one of the most recognized specialists in climate crisis. He has visited the CosmoCaixa Science Museum in Barcelona to convince us that we must reduce CO₂ emissions to zero. Because there is no other option.

Although there are more satellites orbiting the planet continuously sending high-resolution images and atmospheric data, radars that detect precipitation in real time, meteorological stations, rain gauges, radiosondes, and supercomputers capable of performing calculations on a scale unthinkable just a decade ago, it is still difficult to know exactly if a strong storm will unleash, where and when it will do so, and how much rain it will leave.

The rains that have fallen during the few days we have had in the month of October have been exceptional in some regions, with records of more than 200 or 300 l/m² in some cases and torrential downpours that have caused serious consequences, such as floods. Some exceptional figures that might make one think that we have the reservoirs well filled again. But it is not exactly like that.

It has rained a lot these days, and guess which service went down this morning: Rodalies. Obviously, when I say that Rodalies is not working, I mean that even what usually functions is not working. The rains caused a slope to collapse, and the train drivers' union refused to work today for safety reasons. And since the Government, Renfe, and Adif fail every day to inform passengers, this morning thousands of users found themselves without trains and, in many cases, without a reinforcement bus service. All the screens at Sants said was that there was no service "due to external causes" (which were the train drivers).

The rain gives no respite. Catalonia is experiencing its fourth consecutive day of downpours and floods across a large part of the country this Tuesday. Once again, Es-Alerts have sounded on the mobile phones of many Catalans from the Terres de l'Ebre to the Gironès. Once again, several roads have been rendered impassable due to accumulated water, and images of firefighters rescuing people trapped by water inside cars have been repeated. The forecast is for the storm to last until after midnight and for the downpours to continue this Wednesday, especially in the coastal, pre-coastal, Pyrenees, and western Pre-Pyrenees regions with varying intensity.

The alert due to the risk of torrential rain and a "Mediterranean mini-hurricane" has forced theaters, cinemas, concert halls, and festivals in about twenty regions to cancel the activities scheduled for this Saturday starting at eight in the evening, in accordance with the resolution published by the Interior Department. The affected regions are Alt Empordà, Alt Penedès, Baix Empordà, Baix Llobregat, Barcelonès, Garraf, Garrotxa, Gironès, Maresme, Pla de l'Estany, Selva, Vallès Occidental, Vallès Oriental, Alt Camp, Baix Camp, Baix Penedès, Osona, Ripollès, Tarragonès, and Moianès.

In Santa Bàrbara, Victòria street is known by the popular name "el barranquet" (the little ravine). And popular names never lie. Because no matter how much the urban layout tries to hide it, it is the natural path of the Pelós ravine through the center of town. It crosses the municipality from west to east and, if 290 l/m² fall in 24 hours, as happened this Friday, the water does not remember that there are houses. "The level of the flash flood has risen more than half a meter and even though, preventively, we had installed protective wooden boards in front of the garage door, the force of the current broke them and flooded the ground floor," explained Amaya Pla this noon, from in front of her parents' house.

Yesterday it rained very hard and there were floods in ground floors, basements and the whole works. In Barcelona too, and that is despite the luck we have with the fifteen tanks that collect rainwater, six of which filled up almost to the top. The metro was hit hard, so that in the afternoon, hours later, there were still sections without service.

The effect of the torrential rains this Wednesday night has once again highlighted the weaknesses of the railway network. A circulation stoppage has affected the R2, R2 North, and R11 lines almost all day between Barcelona (Sant Andreu) and Granollers Centre. The reason? The rain caused two new holes to appear in the ground of the tracks, very close to the point where last July a large sinkhole swallowed a crane from the Rodalies construction works, at the height of Vallbona. Circulation resumed this afternoon shortly before 5:30 PM, and trains will progressively recover their usual schedules, as reported by Renfe. For now, the alternative bus service is being maintained.

Almost two years after the tragic DANA of 2024, the Generalitat Valenciana has once again been late, and last night it sent an ES-Alert when the rains that affected the province of Valencia had already been torrential for more than an hour. Specifically, at 10:08 p.m., it broadcast a message to all mobile phones in the area informing about the risk of flooding and asking to limit travel, in addition to moving to higher floors if an increase in water level was detected.

The storms this Thursday afternoon across Catalonia have caused havoc in the territory. According to the Meteorological Service of Catalonia (Meteocat), the downpours have locally discharged with torrential character. One of the most notable records occurred in Montsec, where 78.6 mm accumulated in three hours. The intensity of the storm has caused mobility problems. The first Rodalies line affected was the R3, interrupted between Vic and Ripoll due to a tree falling on the tracks. Lines R1, R2 nord, R11, RG1, R13, and R14 also stopped working, which led to traffic jams at various points on the road network. Around nine o'clock this Thursday night, however, some trains gradually resumed their usual frequency.

We've just left behind an exceptionally rainy winter. It had been thirty years since we'd had such a wet winter, and it even ranks among the four wettest winters on record. This situation has filled reservoirs to capacity – the inland basins are at 92% – and saturated forests and rivers across the country. After this historic period, the astronomical spring is now upon us. The spring equinox will occur this Friday at 3:46 PM. We must remember that this is one of the rainiest seasons of the year in our country. Therefore, the question arises: after the abundant rainfall during the winter, will it continue to rain so much this spring?

Throughout March, the start of pollination in trees like the plane tree, willow, and elm typically heralds the arrival of spring. However, this also marks a critical time for allergy sufferers, who must begin taking precautions to minimize pollen-induced symptoms. This year, the low temperatures that have characterized the beginning of the year have meant that winter pollens—from cypress, ash, and hazel—didn't release pollen until the end of February—somewhat later than usual—but, conversely, historical averages have been exceeded since the beginning of the year. Combined with a forecast of warm and rainy weather for March, it seemed that allergy sufferers would have an easier time coping with spring this year, as rainfall causes much of the tree pollen to fall to the ground, thus concentrating it in the air. However, the rainfall has fueled the plants, causing them to bloom more intensely, and the pollen levels released by herbaceous plants and olive trees will last longer than usual, complicating daily life for allergy sufferers. This is the spring pollen forecast from the Aerobiological Network of Catalonia (XAC), published this Tuesday by the Institute of Environmental Science and Technology of the Autonomous University of Barcelona (ICTA-UAB). Its aim is to provide preventative care for people with pollen-related conditions. "Although all this rain may have washed a lot of pollen onto the ground, it has also resulted in very strong trees that will produce abundant flowers because they will be well-watered," explained botanist and head of the XAC, Jordina Belmonte. Therefore, they recommend that allergy sufferers protect themselves, even with masks and goggles. This forecast may change depending on the weather.

According to Belmonte, the risk of allergies could decrease if the heavy rainfall that has been occurring since the beginning of the year continues. "This would help clear the air and allow pollen to fall as it has been," noted the ICTA-UAB researcher. Meteorologists predict that March will be rainier than usual, she added, a situation that could also lead to higher than normal temperatures and shorten the pollination period for herbaceous plants. More episodes of strong winds from pollen-free areas would spread the high concentrations expected in Catalonia. Regarding the types of pollen that are increasing most significantly, cypress, plane tree, olive, and ash pollen stand out. However, Belmonte emphasized that this varies depending on the location, since "not all pollens behave the same way everywhere." "We need to debunk the myth that there is more and more pollen in the air, since there are places where there is less and less," he explains.

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The extraordinary rainfall of recent months has filled most of Catalonia's reservoirs to their maximum capacity. The latest to reach full capacity is the Guiamets reservoir in the Priorat region. This is newsworthy because it's only the second time it has reached 100% capacity since 1978, when official records began. The first time was in May 2004, 22 years ago. This is confirmed by data from the Ebro River Basin Authority (CHE) provided to ARA by the Baix Priorat irrigation community. It's worth noting that at the beginning of December, this reservoir was only at 4% capacity, and for much of the autumn it remained at 1%. Therefore, it has gone from being empty to overflowing in just three months.

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Last week's anticyclone was a mirage. After an exceptionally rainy winter, this first week of March, and of meteorological spring, has brought another turn for the worse, and a severe one at that. A pocket of cold air located between the south of the Iberian Peninsula and North Africa has generated a new low-pressure system, named... Regina by the Portuguese meteorological agency. Initially, it will affect the Canary Islands and the Gulf of Cádiz area, and in our region, for the time being, it will bring clouds, a lot of suspended dust, some showers or drizzles accompanied by mud, maritime winds, and rough seas.

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The rainfall in the western Mediterranean during the first two months of this year has been a third more torrential compared to the period before the planet warmed by 1.3°C. This is the conclusion of a report published this Thursday by the international group of scientists from World Weather Attribution (WWA), which analyzed the exceptional rainfall at the beginning of 2026 in northwest and southeast Spain, southern and northern Portugal, and northern Morocco. Specifically, the report concludes that in the southern regions, the increase in rainfall intensity has been 36%, while in the northern regions it has been 29%. Experts highlight the "unusual number" of storms and low-pressure systems that have affected the entire Iberian Peninsula and northern Morocco during January and February, winter months that are typically dry in Spain. In this period alone, nine major storms have already hit, an extraordinary number. The study attributes this increase in extreme weather events to human activity, specifically carbon dioxide emissions. Experts combined observed increases with climate model simulations, and the results demonstrate that human activity is the direct cause of at least an 11% increase in rainfall intensity in the northwest of the Iberian Peninsula. "Weather patterns that were once more adaptable are now becoming more dangerous disasters, and that is exactly what climate change means, with increasingly intense and severe rainfall," explains David García García, one of the study's authors and a professor in the Department of Applied Mathematics and Aerospace Engineering. The epicenter of the extraordinary rainfall of 2026 was the municipality of Grazalema, in Cádiz, where in just a few days the amount of rain that usually accumulates over an entire year fell, exceeding 2,000 liters per square meter and causing widespread damage. In addition to the exceptional and intense rainfall, the report also highlights the episodes of hurricane-force winds that the Iberian Peninsula has experienced in recent weeks. This highly unstable weather pattern, according to the same study, has resulted from several factors. One of them has been the presence of high pressure systems—anticyclones—over northern Europe, causing an atmospheric blocking pattern that has diverted the jet stream and the usual circulation of storms towards lower latitudes. But it's noteworthy that this series of storms has been "supercharged" by atmospheric currents that have brought significant moisture from a major marine heatwave in the western Atlantic. This combination, a consequence of global warming, has intensified rainfall events in our country.

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