Météo-France places again the Yvelines (78) under red heatwave alert starting from Saturday, July 11, 2026 at 12:00. Temperatures could reach up to 37 °C from Saturday through Tuesday, July 14, posing a serious health risk for everyone, regardless of age or health status.
To prepare for this latest phase, the prefect brought together state services and the department’s mayors, and activated the departmental operations center. A number of orders are being issued to tightly regulate life across the territory for the duration of the alert.
In light of a severe fire risk and conditions favorable to rapid fire spread, the prefect has issued an order banning the display of fireworks and festive fires across Yvelines from July 11 to 15, 2026. Exemptions may be granted on a case-by-case basis, where safety conditions permit and after a favorable recommendation from the Departmental Fire and Rescue Service (SDIS 78).
This ban lands right in the middle of the July 14, 2026 celebrations. Before you head out, we recommend checking with your local municipality whether the planned fireworks display will go ahead, be adjusted, or be cancelled altogether.
A prefectural order also bans, until further notice, sporting events, competitions, gatherings, and collective training in the department. Exemptions may still be possible for aquatic or nautical activities, as well as for facilities with capable installations ensuring participants' safety. For example, the Versailles Ironman has been cancelled.
Other measures signed on July 10, 2026 round out the package: a temporary halt to outdoor construction work and tighter controls on the sale and consumption of alcohol in public spaces. The goal remains the same: curb heat exposure and protect the public.
Swimming is only allowed at designated and supervised sites (recreational bases, pools, and aquatic centers). It remains prohibited in the Seine, which is extremely dangerous due to strong currents, a risk worsened by the thermal shock from the temperature difference between water and air.
The Seine zone, in the northern part of the department, is in drought alert since Monday, July 6, while other zones remain on alert. In the affected municipalities, water-use restrictions are being implemented to preserve the resource, which you can follow on a commune-by-commune basis at VigiEau:
Another priority to watch—illegally opening fire hydrants (the so-called "street pooling") is strictly prohibited. It deprives firefighters of a vital resource, weakens the drinking-water network, and can delay emergency responses. This offense carries up to five years in prison and a fine of €75,000.
Older adults, people with disabilities, those living with chronic illnesses, pregnant women, infants, and individuals who are isolated are the most vulnerable. They can sign up on the municipality’s registry of vulnerable people so the town hall can check in on them regularly. Newly refurbished reception centers are open, and to direct a homeless person to shelter, simply call 115 (free of charge).
To get through this heat episode, drink regularly—don’t wait to feel thirsty—spend several hours each day in a cool place, limit your outings to the hottest parts of the day, and avoid any outdoor physical exertion. A free information line, 0 800 06 66 66, is available from 9 a.m. to 7 p.m. until the end of the episode, and you can find all the government’s official advice on staying safe in the heat at the following link: official government tips. In an emergency, call 15 (SAMU), 18 (fire department), or 112 (European number).
Dates and Opening Time
From July 11, 2026 to July 15, 2026
Location
Yvelines
yvelines
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