Guide
Yellow, orange and red: how weather warnings work
Warning levels describe consequences, not just numbers. Here's what they mean and how you should act on them.
Since 2021, SMHI has used a consequence-based warning system with three levels. What matters is no longer simply how many metres per second the wind is blowing, but the consequences the weather is expected to have where it occurs. The same wind strength can therefore trigger a yellow warning in a mountain municipality and an orange one in a densely built coastal area.
The three levels
| Level | Means | Typical consequences |
|---|---|---|
| Yellow | Certain risks to society and the public | Wet roads, loose objects on the move, occasional traffic disruption. |
| Orange | Serious consequences | Fallen trees, power cuts, cancelled departures, damage to buildings. |
| Red | Very serious consequences | Widespread damage, danger to life, breakdown of key societal functions. |
In addition to the warnings there's a *notice of difficult weather* – a lighter heads-up about weather that doesn't reach warning level but can still cause disruption, such as icy patches in the morning or heavy showers.
Land and sea are warned differently
At sea, separate levels are used because a wind strength barely noticeable on land can be decisive on the water. Gale means a mean wind of at least 14 m/s, storm at least 25 m/s and hurricane at least 33 m/s. A gale warning effectively means leisure boats should stay in harbour, regardless of whether any warning is in force on land at all.
Also remember that warnings are based on mean wind. Gusts are typically 1.3–1.6 times higher, and it's the gusts that bring down trees and rip off roofs. Read more in the wind guide.
What to do at each level
At yellow level it's usually enough to bring in loose items, secure parasols and trampolines, and allow a little extra travel time. At orange you should avoid unnecessary journeys, stay away from forests and harbour piers, charge your phone and prepare for power cuts. At red warning level you should stay indoors, follow the authorities' information, and avoid all time outdoors where trees, building parts or water could pose a danger.
Warnings are forecasts, not promises
A warning is issued when the probability of a given consequence is high enough – not when it's certain. An orange warning passing without anything happening doesn't mean it was wrong; it means the outcome landed at the milder end of an uncertain range. The opposite is also true: local damage can occur even at yellow level.
See what the warned wind strength actually looks like in the visualiser before you decide whether to head out.
Visualise wind