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Hailstorm cancels Vuelta stage as riders seek safety

On Monday, stage 3 of La Vuelta a España, the cycling race, was cancelled after a hailstorm forced riders to take cover and left hail covering the road. Let’s take a look at what happened! www.youtube.com/watch?v=ddn7... 1/14

youtube.com

YouTube video by SBS Sport

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Tim Raupach @timraupach.com · 28/08/2026

Devastating scenes from the terrible flood in Nepal. There will be lots of complex causes for this individual event but it does raise the question of whether mountain destabilisation is accelerating. www.nytimes.com/2026/08/27/c...

nytimes.com

Climate Change Raises Risk of Disasters Like Nepal Floods (Gift Article)

Glaciers and permafrost in the Himalayas are melting faster as temperatures rise, though scientists are still studying the exact causes of this week’s landslide.

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These kinds of events highlight the damage and disruption that hail can cause, and put more focus on our ongoing work to better understand how these complex events may change as the climate warms. 14/14

And Zhang et al. (www.nature.com/articles/s41...) projected increasing hail damage potential in general, but a locally varying signal in southwest Europe with both increases and decreases across the Pyrenees region. 13/14

Rising global hail damage potential in a warming world - Nature

Hailstone trajectory simulations conducted under historical and future scenarios show a shift towards larger hailstones, resulting in global hailstorm-induced damage potential increasing by around 40%...

Future hail projections remain highly uncertain. For hail frequency changes with global warming, our recent work showed a general poleward shift in hail conditions, but no significant projected changes over the Pyrenees (adapted from www.nature.com/articles/s41..., CC-BY-4.0). 12/14

For example, for frequency of very large hail (over 5 cm), Battaglioli et al reported an increasing trend in Europe from 1950—2023 (www.nature.com/articles/s41..., CC-BY-4.0). 11/14

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What about climate change? This is a hail-prone region so storms like this are not unusual in summer. We also can’t say any one storm was “caused” by climate change. But we can test whether storm environments are changing over time, and if storms are getting more or less frequent or severe. 10/14

It’s important to keep in mind that actual hail is usually highly localised within larger hail-prone regions, and hail-prone environments often do not produce any hail at all! That's because even the most hail-prone environment requires a storm to be triggered before you can get hail. 9/14

The European Severe Storms Laboratory’s more sophisticated forecast also showed probabilities of up to 60% for large hail, in regions around where the hail occurred (www.stormforecast.eu). 8/14

So was there instability and wind shear in this case? Yes, at least in the vicinity, in a model forecast (adapted from charts.ecmwf.int, CC-BY-4.0). 7/14

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We often consider the atmospheric “ingredients” for hail. Two common ones are instability (propensity for updrafts to form) and wind shear (difference in wind by height). If you have lots of instability and wind shear together, hail is more likely and the environment is “hail-prone”. 6/14

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Hailstorms are small in scale, so it’s hard to forecast or model exactly where and when hail will happen. But we can consider whether the atmosphere is more or less likely to produce hail. 5/14

Some protruding clouds appear in satellite imagery at that time, likely developed by strong updrafts that can support hail growth (MTG GeoColour RGB with MSG IR10.8 in the background, view.eumetsat.int). 4/14

The hailstorm hit when the riders were 15 km from the stage finish, cycling through Mont-Louis, at about 17:30 CEST (15:30 UTC). Radar data at that time show high reflectivities (over 50 dBZ) indicating the presence of large particles and lots of rain (zoom.earth/maps/radar/#...). 3/14

The storm was in the eastern French Pyrenees. This region is no stranger to hail — the Pyrenees is a well-known hail hotspot. This map shows where we get the most frequent hail environments in Europe (www.nature.com/articles/s41... CC-BY-4.0). 2/14

Hailstorm cancels Vuelta stage as riders seek safety

youtube.com

YouTube video by SBS Sport

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Tim Raupach @timraupach.com · 07/08/2026

Differences between hail/no-hail cases are explained by entrainment theory. Hail cases had more shear to produce wider updrafts, and more humid surroundings. Together this led to less updraft buoyancy dilution and more realisation of instability into vertical motion, supporting large hailstones. 3/4

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Tim Raupach @timraupach.com · 07/08/2026

Hail in the tropics has high uncertainty. It occurs, but rarely, and observations are sparse. Satellite data often indicate hail signatures in the tropics, but these can be ice aloft that melts before it reaches the ground. So we tested how often this happens using simulations. 2/4

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Tim Raupach @timraupach.com · 07/08/2026

In this new paper with Sarah Bang and John Allen, we used simulations to examine satellite hail detections in the Australian tropics. Roughly 1/4 of the simulations produced damaging hail at the surface. 1/4 rmets.onlinelibrary.wiley.com/doi/10.1002/...

Tim Raupach @timraupach.com · 04/08/2026

It’s great to be in Fukuoka for #AOGS2026. For this Sydneysider, experiencing WBGT over 34C also really puts heat-stress projections into perspective.

Tim Raupach @timraupach.com · 03/08/2026

Still amused at atmospheric science journal proofs coming back with "reanalyses" - as in the plural of reanalysis - changed to "reanalyzes".

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Tim Raupach @timraupach.com · 19/07/2026

Just spent a wonderful week visiting Uluṟu and Kata Tjuṯa on Anangu land. Peaceful and magical places.

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Tim Raupach @timraupach.com · 10/07/2026

Wow, @egu.eu really badly wants candidates for treasurer and ECR union rep. To their credit I normally skim-read these emails but after the 30th identical email I did read it properly.

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Tim Raupach @timraupach.com · 10/06/2026

How much is climate change already costing us? New work by Timothy Neal and Ben Newell shows that in New South Wales, Australia, that number is on average about $20k in lost income per person per year. Climate change is already a quality-of-life issue. theconversation.com/climate-chan...

theconversation.com

Climate change has already made Australians in one state much poorer, and more’s to come

It’s time to recognise climate change for what it is. A new study shows it’s a current and ongoing threat to our standard of living.

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Tim Raupach @timraupach.com · 09/06/2026

Interesting example of a compounding event - March 2025 in Türkiye was so warm that fruit trees flowered early. Then hailstorms and cold temperatures came in April. Fruit crops were ruined and prices doubled for months. From this paper by @regclimo.bsky.social et al: www.nature.com/articles/s43...

Compound weather and climate events in 2025

Nature Reviews Earth & Environment - Compound weather and climate events in 2025

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Tim Raupach @timraupach.com · 09/06/2026

This is an excellent recap of compound weather and climate events in 2025. It is also a great explainer of the different types of compounding that can occur, with strong examples. www.nature.com/articles/s43...

ARC 21st Century Weather @21stcenturyweather.bsky.social · 04/06/2026

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Reposted by Tim Raupach

New research led by Tim Raupach and Steven Sherwood and published in Nature Climate Change suggests the atmospheric conditions that favour hail formation are shifting towards cooler regions and cooler times of the year. For more: 21centuryweather.org.au/hail-conditi...

21centuryweather.org.au

Climate change shifting hail risk towards winter crops

Hail conditions on the move as winter crops face rising risk New research led by UNSW suggests that as the climate warms, the conditions that produce hailstorms are drifting towards the poles, leaving...

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Reposted by Tim Raupach

UNSW Climate Change Research Centre @ccrc.bsky.social · 04/06/2026

Where will hail risk increase in a warmer world? A new Nature Climate Change study by CCRC & ICRR researchers finds hail-prone conditions are shifting poleward, with winter hail risk projected to increase in some agricultural regions.

Shifting hail hazard under global warming and effects on crop hail risk - Nature Climate Change

How hailstorms change with warming is not well understood. Here the authors use global projections with different hail proxies to show that hail-prone conditions shift polewards under warming, also sh...

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Tim Raupach @timraupach.com · 03/06/2026

Coauthors on the paper are Raphael Portmann, @christiansiderius.bsky.social, and Steven Sherwood.

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Tim Raupach @timraupach.com · 03/06/2026

In our new paper in Nature Climate Change, we show that hail conditions are projected to shift poleward with climate change, and that summer decreases and winter increases in hail hazard mean that winter crops may face rising risks from hail. www.nature.com/articles/s41...

Shifting hail hazard under global warming and effects on crop hail risk - Nature Climate Change

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Tim Raupach @timraupach.com · 29/05/2026

It's a good day when there's a new @boardsofcanada.bsky.social album out.

Tim Raupach @timraupach.com · 28/05/2026

Important new hail work by Zhang et al., in @nature.com today. Under warming scenarios globally, large hailstones become more frequent and smaller hailstones decline (with regional variation). Another reminder that reducing greenhouse gas emissions is imperative for a safer future. rdcu.be/fk8Fd

rdcu.be

Rising global hail damage potential in a warming world

Nature - Hailstone trajectory simulations conducted under historical and future scenarios show a shift towards larger hailstones, resulting in global hailstorm-induced damage potential increasing...

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Our poster session for #EGU26 ITS4.4 is very active with lots of great discussion - interdisciplinary science from flooding rain, hail, to heat stress and financial risk.

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Finishing up the talks for ITS4.4 at #EGU26, Jung-Ching Kan talks about heat impact forecasts for Sweden using machine learning.

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Nicolò Ardenghi now tells us about decision-making for managing important climate risks in Venice, in ITS4.4 at #EGU26.

Staying in finance at ITS4.4, Marco Maneta now joins us online to talk about climate risk financial modeling. #EGU26

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Moving to the financial sector in ITS4.4 at #EGU26, we now have Chiara Cagnazzo talking about the @ecmwf.int C3S climate services for assessing physical climate risk.

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Till Sterzel now presents work on urban-planning adaptation under climate change, in ITS4.4 at #EGU26.