Record-shattering March temperatures in Western North America virtually impossible without climate change

The #heatwave poses a significant public health threat, particularly given its timing early in the season. The persistent #HeatDome is creating stable atmospheric conditions, suppressing cloud formation and precipitation, while allowing temperatures to climb, thus expected to cause persistent #heat. #ExtremeHeat is the leading cause of weather-related fatalities in the US. Limited overnight cooling and the lack of air-conditioning is expected to add to the heat stress, particularly for vulnerable populations in these parts who are not acclimatised to the heat, including tourists from cooler countries (CNN, 17 March 2026). This heat dome is breaking records for this time of the year, and is in some ways comparable to the persistent system that caused the 2021 Pacific Northwest (PNW) Heatwave. The PNW event occurred later in the year, in June, with temperatures of up to 48.9℃ (120℉) causing hundreds of fatalities (BBC, 17 March 2026).

https://www.worldweatherattribution.org/record-shattering-march-temperatures-in-western-north-america-virtually-impossible-without-climate-change/

#ClimateScience
#WeatherAttribution
#ClimateCrisis

Increasingly severe rainstorms put people and structures built on floodplains at risk

Since 16 January, nine named storms have battered the western #Mediterranean, with #Spain, #Portugal and #Morocco hardest hit.

In Spain, #flooding and infrastructure damage from heavy winds forced over 12,400 evacuations, affected 115,000 people in 19 villages in the Sierra de Cádiz, and led the Spanish Government to commit more than €7 billion in aid, with an additional €1.78 billion from the #Andalusian regional government.

Portugal recorded six fatalities during #Storm Kristin, with winds up to 202 km/h leaving one million people without electricity and causing widespread structural damage, and the Portuguese Government has already committed to supporting the reconstruction with a package of €3.5 billion.

In northern Morocco, flooding caused 43 deaths, displaced 300,000 people and inundated 110,000 homes, prompting a €280 million recovery plan.

While the high winds were exceptional and caused part of the damages, the most severe impacts are due to the heavy rain accompanying each storm that led to flooding in various regions. Later in the season the increasingly saturated soils also contributed to the flooding.

https://www.worldweatherattribution.org/increasingly-severe-rainstorms-pose-growing-risk-for-people-and-structures-build-in-the-floodplains/

#ClimateCrisis
#ClimateScience
#WeatherAttribution
#ExtremeWeather

Intense two-week heatwave in Fennoscandia hotter and more likely due to climate change

In #Namsskogan and #Gartland, #Norway, temperatures reached 30°C and more for 13 days in a row, while in #Ylitornio, #Finland maximum temperatures stayed above 25°C for 26 days in a row, something hitherto unknown this far north in #Europe. While many heat records in the three countries were set in 2018, the last time a similarly strong #heatwave affected #Fennoscania, the duration of this 2025 event put enormous strain on the #healthcare system, with many more hospital admissions, and hospitals struggling to cool buildings (NRK, 2025; TV2, 2025). At least 28 people in Finland (YLE News, 2025), 31 in Sweden (GP, 2025) and 8 in Norway (NTB, 2025) died in July due to drowning.

https://www.worldweatherattribution.org/intense-two-week-heatwave-in-fennoscandia-hotter-andmore-likely-due-to-climate-change/

#ExtremeWeather
#WeatherAttribution

Climate change drives record-breaking heat in Iceland and Greenland challenging cold adapted ecosystems and societies

On May 15, #Egilsstaðir Airport recorded 26.6°C, breaking the previous record for #Iceland’s highest May temperature, while regions of the country saw temperatures more than 10°C above average (Icelandic Met Office, 2025). The #Ittoqqortoormiit station in #Greenland saw temperatures reach 14.3°C on May 19, which is more than 13°C above the May average daily maximum temperature of 0.8°C (#DMI, 2025).

These high temperatures were caused by a steady flow of warm air from the south, caused by a high-pressure system near the #Faroe Islands and a low-pressure system south of #CapeFarewell. This #weather setup lasted for about nine days, bringing unusually warm weather to the area. While similar patterns have happened before, this #heatwave stood out because it came so early in the year and lasted for so long.

While few impacts have been reported, numerous studies demonstrate that unusually high temperatures early in the year can have significant impacts on local ecosystems. These #ecosystems, adapted to very cold climates, are sensitive to temperature shifts, and disruptions to their delicate balance can lead to consequences not only for the ecosystems themselves, but also for the communities that depend on them.

https://www.worldweatherattribution.org/climate-change-drives-record-breaking-heat-in-iceland-and-greenland-challenging-cold-adapted-ecosystems-and-societies/

#WeatherAttribution
#ClimateScience

Climate change turns warm summer days in England into health threat

As the week progresses, southerly winds are drawing in warmer air, pushing temperatures in the South of #England toward #heatwave conditions by the weekend of the 21st and 22nd of June (Met Office, 2025). In the #UK, a heatwave is officially declared when a location experiences temperatures at or above a specific threshold for at least three consecutive days. These thresholds vary by region based on the local #climate. In cooler areas, such as much of northern and western Britain, the threshold is 25°C. In warmer regions, including Greater #London and the surrounding southeastern areas, the threshold is higher at 28°C.

https://www.worldweatherattribution.org/climate-change-turns-warm-summer-days-in-england-into-health-threat/

#WeatherAttribution
#ClimateCrisis
#Health

Effective emergency management prevented larger catastrophe after climate change fueled heavy rains in Central Mississippi river valley

The #floods inundated large rural areas including agricultural fields, especially in #Arkansas which has resulted in an estimated 78 Million USD of damage due to losses in fields that were already planted. Larger losses were avoided due to the timing of the floods before other #crops like #peanuts and #cotton were planted, and since there is still a window to replant crops like #corn and #soybeans.

Based on gridded data products, we find that the extreme #rainfall event over the study region is relatively rare, expected to occur in today’s #climate only once every 90-240 years across different observational and reanalysis datasets. However, in a 1.3°C cooler climate, extreme rainfall such as observed would be even rarer. The best estimates for the increase in likelihood for the 2025 event associated with this warming is between a factor 2 to 5, and the increase in intensity for an event of equivalent rarity as observed is 13-26%.

To quantify the role of human-induced #ClimateChange in this increased likelihood and intensity we also analyse climate model data over the study region for the historical period. The best estimate of the synthesised result, combining observations with climate models, is about a 40% increase in likelihood and about a 9% increase in intensity. These estimates are smaller than the observed trends due to large discrepancies between the climate model results. While some models show increases similar to or larger than the observed trends, others show weaker or even decreasing trends.

In contrast, #ClimateModels consistently project that extreme precipitation events such as the one observed in April 2025 will become more frequent and intense in the future as global temperatures rise. Under current climate policies – which will lead to warming of approximately 2.6°C by 2100 – such extremes are expected to approximately double in likelihood again, and increase in intensity by about a further 7%.

As the moisture that fuelled the rainfall event was partly coming from the #GulfOfMexico we also assessed the role of climate change in the sea surface temperatures. We found that these waters were heated by approximately 1.2 °C (2.2 °F) due to human-caused climate change, and such #ocean conditions are now about 14 times more likely than in a cooler pre-industrial world. This contributed to higher #evaporation rates, increasing the availability of moisture in the rainfall event.

The strong observed trends in precipitation extremes in this region are also found in other studies using different methods, across different regions, including the Central #Mississippi river valley and are assessed as being attributable to climate change by the #IPCC AR6 report.

In conclusion, due to (1) the observed trends that are (2) in line with IPCC assessments and other literature in the region, and (3) the clear emergence of a climate change signal with further #warming in all climate models as well as (4) the availability of more moisture due to higher SSTs, we state that climate change amplified the heavy rainfall leading to the floods and that the estimate from observations and models combined of a 9% increase in intensity and 40% increase in likelihood is conservative and the role of climate change could be as large as the observations alone suggest

Despite being an extremely complex event, with tornadoes, flash floods, riverine floods and landslides overlapping, the US National Weather Service made a tremendous effort to provide early warnings for the floods, in some cases up to a week in advance of river crests. These early warnings allowed state and local emergency departments to prepare, inform the public, and evacuate those at highest risk. While any loss of life is devastating, the outcomes of this event point to the effectiveness of decades-long investments made in forecasting, #EarlyWarningSystems, and #forecast-based action.

Nearly half of NWS field offices are facing vacancy rates of 20% or more, double the short-staffing levels of a decade ago. Former NWS leaders have recently warned that layoffs could impact the ability of NWS offices to respond to extreme weather events and keep people safe.

https://www.worldweatherattribution.org/effective-emergency-management-prevented-larger-catastrophe-after-climate-change-fueled-heavy-rains-in-central-mississippi-river-valley/

#ExtremeWeather
#WeatherAttribution

Extraordinary March heatwave in Central Asia up to 10 °C hotter in a warming climate

In March 2025, Central #Asia experienced an unusually intense #heatwave, with temperatures reaching record highs across the region, reaching maxima of 30.8°C #Jalalabad in #Kyrgyzstan, 29.4°C #Namangan, 29.1°C #Fergana, in #Uzbekistan and minimum temperatures of 18.3°C in #Shahdara, making it the hottest March night in Kazakhstan’s history.

https://www.worldweatherattribution.org/extraordinary-march-heatwave-in-central-asia-up-to-10-c-hotter-in-a-warming-climate/

#ExtremeWeather
#WeatherAttribution

#ClimateChange increased the likelihood of wildfire disaster in highly exposed Los Angeles area

Coastal Southern #California is an environment highly prone to catastrophic #wildfires. The destructiveness of a fire thus also strongly depends not only on the #weather conditions but also on whether land use and fire management strategies take these characteristics into account. The #PalisadesFire occurred in an officially designated Very High Fire Hazard Severity Zone, while the #EatonFire was only partly within such an area. This means fire risk has always been very high and building regulations require at least 200 ft of vegetation management around structures within the designated Very High Fire Hazard Severity Zones. Post-fire assessments will check compliance with these requirements.
Looking at weather observations, in today’s climate with 1.3°C #GlobalWarming relative to preindustrial, the extreme Fire Weather Index (#FWI) conditions that drove the #LA fires are expected to occur on average once in 17 years. Compared to a 1.3°C cooler climate this is an increase in likelihood of about 35% and an increase in the intensity of the FWI of about 6%. This trend is however not linear, with high FWI conditions increasing faster in recent decades.

https://www.worldweatherattribution.org/climate-change-increased-the-likelihood-of-wildfire-disaster-in-highly-exposed-los-angeles-area/

#WeatherAttribution

Conflict, poverty and water management issues exposing vulnerable communities in #Africa

The rainy season from July to Sept. 2024 was marked by extremely heavy and sometimes unprecedented rainfall in large parts of the #Sahel region, leading to catastrophic #flooding in #Sudan in Aug. and in #Nigeria, #Niger, #Chad and #Cameroon in Sept. In total more than 2000 people lost their lives and millions were displaced.

https://www.worldweatherattribution.org/conflict-poverty-and-water-management-issues-exposing-vulnerable-communities-in-africa-to-extreme-floods-that-are-now-common-events-because-of-climate-change/

#WeatherAttribution
#Extremweather
#ClimateCrisis

World Weather Attribution

#ClimateChange and high exposure increased costs and disruption to lives and livelihoods from #flooding associated with exceptionally heavy rainfall in Central #Europe

"As the event is by far the heaviest ever recorded, the exact return time is difficult to estimate based on only about 100 years of observed data. We use a 100 year return-time for the rest of the analysis..."

https://www.worldweatherattribution.org/climate-change-and-high-exposure-increased-costs-and-disruption-to-lives-and-livelihoods-from-flooding-associated-with-exceptionally-heavy-rainfall-in-central-europe/

#WeatherAttribution
#ExtremeWeather
#ClimateCatastrophe