Weather warnings in Switzerland: understanding the danger levels
MeteoSwiss rates weather hazards on a scale of 1 to 5 and only issues a warning from level 2 upwards. Here is what each level means, the thresholds that trigger it, and why the word « vigilance » belongs to a different system.
The five danger levels
| 1 | No or minor danger | The weather is developing normally for the season, with no particular danger. Significant phenomena may still occur locally, even when no warning has been issued. |
| 2 | Moderate danger | A weather event is expected which, while potentially dangerous, is not unusual for the season. |
| 3 | Considerable danger | A weather event is expected whose intensity, at the edge of the seasonal norm, should be taken seriously. |
| 4 | High danger | A dangerous weather event of an intensity unusual for the season is expected. |
| 5 | Very high danger | A very dangerous weather event of exceptional intensity is expected. |
Not every phenomenon uses all five levels. Severe thunderstorms are graded only at levels 3 and 4: their strength, timing and exact location remain too uncertain hours in advance for a full scale to mean anything. Ground frost, slippery roads and storm advisories on lakes use level 2 only.
Wind thresholds
Gust speed at which each level is reached, by region and altitude.
| Region | 2 | 3 | 4 | 5 |
|---|---|---|---|---|
| Plateau / Jura, < 1000 m | 70 km/h | 90 km/h | 110 km/h | 140 km/h |
| Plateau / Jura, ≥ 1000 m | 100 km/h | 130 km/h | 160 km/h | 200 km/h |
| Préalpes, Alpes et sud des Alpes, < 1600 m | 70 km/h | 90 km/h | 110 km/h | 140 km/h |
| Préalpes, Alpes et sud des Alpes, ≥ 1600 m | 100 km/h | 130 km/h | 160 km/h | 200 km/h |
Rain thresholds, north of the Alps
Accumulated precipitation over the stated period. South of the Alps the thresholds are markedly higher — 70 mm in 24 hours for level 2 against 30 mm in the north — because such amounts are far less rare there.
| Period | 2 | 3 | 4 | 5 |
|---|---|---|---|---|
| 12 h | 20 mm | 35 mm | 60 mm | 100 mm |
| 24 h | 30 mm | 50 mm | 80 mm | 120 mm |
| 48 h | 50 mm | 80 mm | 110 mm | 150 mm |
| 72 h | 60 mm | 100 mm | 130 mm | 170 mm |
Snow thresholds, lowlands
Fresh snow depth on the German-speaking Plateau and in the canton of Fribourg below 800 m.
| Period | 2 | 3 | 4 | 5 |
|---|---|---|---|---|
| 12 h | 5 cm | 10 cm | 20 cm | 35 cm |
| 24 h | 10 cm | 15 cm | 30 cm | 50 cm |
| 48 h | 20 cm | 35 cm | 50 cm | 70 cm |
| 72 h | 30 cm | 50 cm | 70 cm | 90 cm |
« Vigilance » or « danger level »?
If you searched for « vigilance modérée », you are using Météo-France's vocabulary, which grades its alerts green, yellow, orange and red. Switzerland uses a numbered scale from 1 to 5 and speaks of danger levels. The two systems do not map term for term: the French vigilance has four levels, the Swiss scale five. Swiss level 2, « moderate danger », is the first that produces a warning, and it is the closest equivalent to a yellow vigilance.
How this site's alerts work
The alerts shown on our pages are not the official MeteoSwiss warnings and do not replace them. We flag a notable instantaneous condition in the model forecast: thunderstorm, heavy rain or snow, or wind of at least 70 km/h — the level 2 threshold in the lowlands. Official warnings rest instead on regional accumulations assessed by forecasters, which we do not reproduce.
For any decision affecting your safety, always consult the official source: the MeteoSwiss hazard map. Consequences on the ground — floods, landslides, avalanches — fall to other federal offices and are published on the joint natural hazards portal.
MeteoSwiss hazard map · Swiss natural hazards portal
Check the weather in a canton
From which level does MeteoSwiss issue a warning?
From level 2, « moderate danger ». Level 1 means the weather is developing normally for the season; no warning is published, which does not rule out significant phenomena locally.
What does an orange warning mean in Switzerland?
Orange corresponds to level 3, « considerable danger »: an event is expected whose intensity, at the edge of the seasonal norm, should be taken seriously.
What wind speed triggers a warning?
On the Plateau and in the Jura below 1000 m: 70 km/h for level 2, 90 km/h for level 3, 110 km/h for level 4 and 140 km/h for level 5. Above 1000 m the thresholds rise to 100, 130, 160 and 200 km/h.
How much rain is needed for a warning?
North of the Alps, 30 mm in 24 hours is enough for level 2, 50 mm for level 3, 80 mm for level 4 and 120 mm for level 5. South of the Alps, level 2 only begins at 70 mm.
Why do thunderstorms have only two levels?
Because a thunderstorm's strength, timing and exact location remain unpredictable hours in advance. MeteoSwiss therefore grades severe thunderstorms only at levels 3 and 4, and damage usually stays highly localised.
Levels and thresholds: « Description des différents degrés de danger », MeteoSwiss, May 2021.