Ahead of the Canadian Grand Prix, the FIA's official weather system indicates a more than 40% chance of rain for Sunday. As a result, Race Director Marques has now declared a 'Rain Hazard'.

According to Article B1.5.11, it is mandatory this year for race control to declare a so-called 'Rain Hazard' as soon as the probability exceeds forty percent that it will rain during the race. This must be done at least two hours before the start of qualifying. The warning remains in effect from the moment it is announced until the signal is given for the end of the race session.

The 'Rain Hazard' therefore says nothing about how much rain is expected or what impact this might have on the race. It is a way for race control to let the teams know that they should be prepared for rain. If this warning is issued less than two hours before qualifying, the teams are permitted to make certain adjustments to the car, even if it is already in Parc Ferme.

In previous years, there was no similar provision in the regulations. In 2025, there was only a provision relating to heat, under which a so-called 'Heat Hazard' could be declared. This comes into effect as soon as the temperature rises above 31 degrees Celsius. In such cases, the cooling system must be connected to the drivers to prevent them from overheating during the race.

Following the FIA's declaration of a 'Rain Hazard' in Montreal, the latest weather forecasts at the Circuit Gilles Villeneuve have since been updated.

According to Weather.com, rain is currently falling down rather lightly at the Circuit Gilles Villeneuve at the time of writing, but things should clear up by the race start at 16:00 local time. Weather.com has the chance of rain at lights out currently at 13% with only a two percent rise predicated at any point during the race. Humidity should be at 71%, while cloud cover is set at 99% for the start. Southeasterly winds should also reach up to 9mph during the Grand Prix.

Things could still change prior to the race start at 21:00 UK time, with drivers and pundits wary of not having done much wet weather running in the 2026 machinery powered 50:50 by electrical power and internal combustion, and with emphasis on energy management and deployment.

So far, only the Barcelona pre-season shakedown and testing during F1's April break have seen the 2026 cars in the wet. Such limited experience in the wet has led Sky F1 pundit Martin Brundle to suggest that drivers are a "little bit scared" of the prospect in the new cars.

Prior to the Miami GP earlier in May, the FIA banned Boost Mode under wet weather conditions, which goes alongside their previous introduction of a 'partial' active aero mode, where only the front wing opens in specific circuit zones in the rain as opposed to both front and rear wings on a dry track.