Spa rain threat could expose biggest unanswered question in F1 2026

Several Formula 1 drivers have voiced their concerns around the potential for wet conditions this season and, with the Belgian Grand Prix weather forecast predicting rain, representative wet running may take place for the first time in this era.

The early forecast for the Belgian Grand Prix places a high possibility of rain on qualifying Saturday, with a chance of rain in Free Practice through Friday as well, while it is currently forecast for a cooler, drier day on grand prix Sunday.

Belgian Grand Prix weather could trigger Formula 1’s first major wet test of 2026

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While there has been the threat of rain at more than one event so far this season, bar an erroneous placing of intermediate tyres at the beginning of the British Grand Prix Sprint, the drivers are yet to undertake proper wet running in a representative session so far in 2026.

That appears set to change at the weekend’s Belgian Grand Prix, with Friday and Saturday looking set for wet weather – meaning the possibility of having to lap Spa in anger in the rain in qualifying.

While the drivers have risen through the ranks racing in all conditions, there is a fear of the unknown amongst them this season.

With narrower tyres coming into play, Pirelli undertook extensive testing for two seasons before finalising its new-for-2026 compounds – albeit on mule cars from the previous era – meaning there has been very little running from any driver in wet conditions on this new generation of cars.

Ahead of the Miami Grand Prix, the FIA announced it has increased tyre blanket temperatures for intermediate tyres on safety grounds, understood to be up to 70°C. While the all-new full wet tyres had been initially slated to run without tyre blankets, teams can heat those tyres to a maximum of 40°C before heading out on track.

One of the few to drive current machinery in representative conditions is Lewis Hamilton, who took part in a wet-weather test at Ferrari’s private Fiorano circuit back in April as Pirelli continues its testing programme.

He revealed he called upon the governing body to raise wet tyre temperatures to aid the drivers, but he feels the 2026 rubber is not as good as what came before it.

“Ultimately, the wet tyres aren’t spectacular in terms of the way that they’ve moved to having no blankets to having low blanket temperatures, and then ultimately they’ve had to build a tyre that works with those low blankets, and the tyres don’t work, so we’re constantly battling the tyres that don’t work,” said the seven-time world champion.

“From my test, I pushed the FIA to raise the blankets. They did it, and from the test, I pushed them to add the blankets onto the extreme tyres, which they have, but that’s still not enough. They’re still a lot worse.”

Pierre Gasly has also driven on the new rubber, undertaking a wet shakedown with Alpine at Silverstone in January, before a wet-weather test with Pirelli for its 2027 tyres at Magny-Cours in May.

Speaking of the experience with a knowing smile in Canada, he turned to the drivers next to him and said with a big laugh: “You guys are gonna be shocked.

“I’m glad I’ve done these two days, yes. It’s gonna be interesting for you guys.

“I mean, I’ve had Silverstone, 20th of January, which was memorable and I think will stay with me forever, but Magny-Cours was also… something.”

Asked what made the experience so challenging, the Alpine driver quipped: “You don’t want me to answer that question.”

He went on to predict later that weekend that, with rain having been forecast in Montréal, the Canadian Grand Prix would be something of an “elimination game” in wet conditions, and that he would “let the others try the inters” on track.

Carlos Sainz was able to elaborate further, and despite having not yet driven in wet conditions this season, he is aware of the complaints from Gasly.

“Never put an inter on on this set of regulations or wet,” he said of his own situation, “so it will be definitely a struggle for the first few laps for us as a team, and understanding what’s going on.

“Many drivers, including Pierre, which did the testing at Magny-Cours, was complaining a lot about the inters and the wets not getting into a range [and] aquaplaning.”

F1 2026 power units also a ‘big problem’ in the wet

Tyres are unlikely to be the only factor in play, though. McLaren’s Oscar Piastri explained the nature of the F1 2026 power units may yet play their part in how drivers respond in the wet.

With the changes in energy deployment over the course of a lap, drivers will have to manage their cars in a different way – which presents another challenge.

Piastri reasoned: “These power units don’t like it when you’re inconsistent, and it’s basically impossible to be consistent in the rain, so there’s going to be a few issues with that, most likely up and down the grid.”

Asked on what exactly will be the main difficulty to navigate in the rain, he added: “Everything. I think the tyres, I don’t know, but not heard amazing things, and the power units, I mean, they’re tricky enough in the dry and consistent conditions, let alone in the rain, so both will be a big problem.

“Obviously, I think the power unit will just be a lap time loss – could be quite big – but obviously getting the tyres into the window or not, the risk factor of that is significantly higher.”

Fernando Alonso agreed, adding in Montréal of future wet conditions: “It’s gonna be a challenge, obviously.

“We don’t have much information, we are one of the teams that never run on wet conditions with this regulation, so for us it’s everything to discover.

“These cars, we know that the deployment is a little bit random, the gearbox is harsh for everybody, so under wet conditions, [it’s] going to be a challenge for everyone to finish the race.”

How might the Belgian Grand Prix unfold this weekend?

Belgian Grand Prix weather: What is the risk of rain this weekend?

Honda confirms timeline for Aston Martin power unit update

How has Pirelli responded?

Pirelli had long stated its mission for the 2026 regulations that, with the full wet tyres having been used decreasingly frequently over time, the brand wanted to “reduce the crossover time” between full wets and intermediates, to make the extreme tyre a more viable strategic option.

While its tread pattern is the same as last season, the smaller diameter and width of the tyres presented the need to adjust ahead of 2026 – likewise, the initial plans to run full wet tyres without the benefit of being warmed up by blankets.

Pirelli motorsport director, Dario Marrafuschi, has previously mentioned the drivers will still be able to make a difference behind the wheel and, in the event of wet sessions, the tyre manufacturer will respond as necessary.

“We’ll collect all the feedback, and then we will make some evaluations,” he said in May of future wet running.

“We can comment that all development work for the wet tyres has been done in the same way as the dry tyres, and obviously the development work last year was done on the [previous] cars and not on the current cars, so there is a bit of unknown, but that’s why once we have raced these tyres, we will draw the conclusions and react if needed, as we always did.”

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