Germany Heatwave 2025: Up to 39°C Forecast — How to Stay Safe

Introduction

Another intense heatwave is moving across Germany, and this one looks serious. The German Weather Service (DWD) has issued forecasts showing temperatures rising sharply from Thursday, with Friday expected to bring the peak — and the DWD has explicitly stated that 39°C "cannot be ruled out." For expats living in Germany, particularly those from cooler climates or those living in older, poorly ventilated apartments, this kind of heat can be genuinely dangerous. This guide covers what to expect, how to protect yourself, and where to get help if you need it.

What the Forecast Says

According to the DWD (Deutscher Wetterdienst), Germany's official national meteorological service, the incoming heatwave will follow a familiar pattern:

• Thursday: Temperatures begin climbing significantly above seasonal averages across most of Germany.
• Friday: The peak arrives. DWD forecasts suggest highs well above 35°C in many regions, with 39°C possible in the hottest spots — typically in western and south-western Germany (Rhine Valley, Baden-Württemberg, parts of Bavaria).
• Weekend: Gradual easing expected, though nights are likely to remain warm and uncomfortable.

These are not just uncomfortable temperatures — at this level, heat becomes a medical risk, particularly for older people, young children, outdoor workers, and anyone with pre-existing health conditions.

Why German Heatwaves Hit Expats Hard

Germany's housing stock was largely built in an era when extreme summer heat was rare. The consequences are very real for residents today:

• No air conditioning in most homes: The majority of German apartments and houses — particularly older buildings — have no air conditioning. Residents rely on ventilation strategies that become less effective as outside temperatures climb.
• Poor nighttime recovery: When overnight temperatures stay above 20–25°C, the human body cannot cool down properly during sleep. After several consecutive hot nights, the cumulative health risk increases significantly.
• Urban heat islands: Cities like Frankfurt, Berlin, Cologne, and Munich retain heat longer than rural areas, making urban apartments particularly uncomfortable and potentially dangerous.
• Unfamiliarity with German heat protocols: Expats new to Germany may not know where public cooling spaces are, or how the local healthcare system handles heat-related emergencies.

Practical Steps to Stay Safe

Here is what you can do right now to protect yourself and your household:

At home:

• Close shutters (Rolläden) and curtains during the day to block direct sunlight — this is the single most effective heat-reduction method in German apartments.
• Open windows only at night and in the early morning, when outside temperatures are lower than inside.
• Place a wet sheet or towel in front of an open window to cool incoming air.
• Use a fan to create airflow, but know that fans do not cool air — they help sweat evaporate from your skin, which is only effective if you stay hydrated.

Hydration and health:

• Drink water consistently throughout the day — do not wait until you feel thirsty.
• Avoid alcohol and heavy caffeine during peak heat hours.
• Cool your wrists, neck, and temples with cold water for rapid body temperature reduction.
• Watch for signs of heat exhaustion: heavy sweating, dizziness, nausea, rapid heartbeat, or confusion. These require immediate rest, hydration, and cooling.
• Heat stroke (no sweating, very high body temperature, confusion) is a medical emergency — call 112 immediately.

Public cooling spaces:

• Many German cities open libraries, museums, and community centres as informal cooling refuges during extreme heat. Check your local city or municipality website.
• Supermarkets and shopping centres are typically air-conditioned and freely accessible.
• Public swimming pools (Freibäder) are an excellent option but expect large crowds on peak days.

Outdoor workers:

• German law requires employers to provide protective measures during extreme heat (shading, breaks, water). If your employer is not doing this, you can contact your local Gewerbeaufsichtsamt (occupational health authority).

Frequently Asked Questions

Is there an official heat warning system in Germany?

Yes. The DWD operates a heat warning system (Hitzewarnung) with two levels: "strong heat load" (starke Wärmebelastung) and "extreme heat load" (extreme Wärmebelastung). You can check current warnings on the DWD website (dwd.de) or via the free DWD WarnWetter app, which is available in German and English.

What should I do if I or someone I know shows signs of heat stroke?

Call the emergency number 112 immediately. While waiting for help: move the person to a cool, shaded place, remove excess clothing, apply cool (not ice-cold) wet cloths to the body, and do not give water if the person is unconscious or confused. Heat stroke is life-threatening and requires emergency medical care.

Are there any official recommendations for vulnerable people?

Germany's Federal Centre for Health Education (BZgA) and the Robert Koch Institut both publish heat health advice. People over 65, pregnant women, young children, and people with cardiovascular or respiratory conditions are in the highest-risk group and should take extra precautions or arrange for someone to check on them regularly during peak heat days.

Conclusion and Next Steps

This heatwave is real, it is imminent, and it requires practical preparation — not panic. Take steps today: prepare your apartment, stock up on water, download the DWD WarnWetter app, and check in on elderly neighbours or vulnerable people in your building. If you are working outdoors, know your rights and talk to your employer. The heat will pass, but staying safe through it requires action now.

Source: iamexpat / German Weather Service (DWD)