Heat Warning – Orange Alert Level announced from Friday, 19 June

Due to the heat warning (orange alert level) that will be issued by MeteoLux for the period from Friday, 19 June until at least Monday, 22 June 2026, the Weather- Flood Risk Assessment Cell (CERI) met today to assess the situation.

According to current forecasts, tropical nights are expected from Friday night into Saturday, with temperatures remaining above 20 °C. From Monday onwards, the perceived temperature could locally reach up to 39 °C.

This meeting also took place in the context of National Day celebrations and the festivities scheduled over the coming days and next week, which require particular attention, especially during gatherings and outdoor events.

The orange alert level is triggered when high perceived temperatures (average Universal Thermal Climate Index (UTCI) equal to or greater than 24 °C) are forecast for at least two consecutive days, indicating a significant level of heat stress. The perceived temperature combines all relevant factors contributing to heat stress: air temperature, humidity, wind speed and solar radiation intensity.

Public authorities remind the population of the possible health impacts and the precautions that should be taken to limit the effects of heat.

Possible consequences:

• Risk of health problems, especially for older persons, young children, people suffering from chronic illnesses or mental health disorders, people taking certain medications, and socially isolated individuals.

• Dehydration or heat stroke (symptoms: body temperature above 40 °C, hot, red and dry skin, headaches, nausea, drowsiness, intense thirst, confusion, convulsions and loss of consciousness).

Recommended precautions:

• Drink plenty of water regularly throughout the day (at least 1.5 litres per day).

• Avoid going outdoors (prolonged and direct exposure to the sun) during the hottest hours of the day (11 a.m. to 9 p.m.).

• Keep your home cool by closing shutters, curtains and windows during the day and ventilating at night.

• Choose light meals with a high water content (fruit, vegetables, etc.).

• Wear a hat or other head covering when outdoors.

• Wear light, loose-fitting and light-coloured clothing.

• Limit physical activity.

• Stay in cool and air-conditioned places whenever possible.

• Keep in contact with vulnerable and at-risk people around you and help them stay in a cool environment.

Some professions are particularly exposed, and specific workplace recommendations are available.

Athletes should also avoid intense physical exertion during the hottest periods of the day.

In the event of heat stroke (high body temperature, headaches, nausea, confusion, etc.), it is recommended to contact a healthcare professional or call 112 in an emergency.

Together, for our protection

The Corps grand-ducal d'incendie et de secours (CGDIS) draws attention to the increased risk of vegetation fires and accidents related to outdoor activities and calls on the public to act responsibly.

Throughout the period, the authorities will closely monitor developments. CERI will meet again on Saturday, 20 June, to review the situation and will provide further information depending on how the situation evolves.

Further information: www.infocrise.lu; www.lu-alert.lu; http://santesecu.lu/canicule; www.itm.public.lu

Participants in CERI: Haut-Commissariat à la protection nationale (HCPN), MeteoLux, Direction de la santé, Corps grand-ducal d'incendie et de secours (CGDIS), Police grand-ducale, Armée luxembourgeoise, ministère de l'Education nationale, de l'Enfance et de la Jeunesse

Issued by: Weather- Flood Risk Assessment Cell (CERI)