Explanation of the danger levels

Enlargement:

The hazard categories numbered 1 to 5 have been determined by the specialist government bodies for natural hazards. Prevailing circumstances are outlined in terms of their potential dangers and their impact on society for each individual category within the various natural hazard types. Whilst the definitions have been made as similar as possible for the same hazard category numbers across the different natural hazards, it is, of course, not possible to make direct comparisons between them. Detailed explanations of the hazard categories for each natural hazard can be found in the menu on the left-hand side of this page.

Frost

Ground frost occurs when the temperature close to the ground (measured 5 cm above the natural ground level) falls to the freezing point or below....

Heat wave

Our perception of heat is affected by the following meteorological parameters: air temperature, radiation from the sun, relative air humidity, and...

Rain

Rain is the most common form of liquid precipitation from clouds, and develops as a result of small, suspended cloud droplets growing into larger...

Slippery roads

Ice on the roads develops as a result of cold and wet conditions.

Snow

Snow is the most common form of solid precipitation and consists of many very small ice crystals. These form at temperatures below -4 °C, and fall...

Thunderstorms

A thunderstorm is a complex meteorological event, characterised by the presence of electrical discharges (lightning) followed by thunder. The...

Wind

Wind is the movement of air in the atmosphere, generally in a horizontal direction. Wind is created as a result of differences in air pressure...