Cold wave

The term «cold wave» describes an unusual fall in temperature that is triggered by the transport of cold air masses into a specific area.

How does a cold wave develop?

A cold wave develops when cold air masses over large areas are brought in. In middle Europe this occurs mainly during winter months when cold air masses are transported from the polar region or from the East. In those northern areas cold air develops to a large reservoir due to low or even missing solar radiation during short autumn and winter days. Particular weather conditions can transport these air masses as far as Central Europe. The fall of temperature is of the order of 10°C within a few hours. Cold air masses are only slowly moving, therefore, a cold wave will normally last for several days.

Cold waves can also develop on other continents. During a cold wave on Rhode Island (USA) temperatures as low as -45°C were measured in January 1994. The cold air masses transport only little moisture. Precipitation occurs as snow or sleet due to temperatures below freezing point. Cold waves can also be accompanied by strong wind. Such a phenomenon is called winter storm.

What type of damage can occur?

Nowadays cold waves directly harm only persons that are poorly protected, for instance homeless people.

Mainly the secondary consequences are responsible for damage: Strong snowfall can trigger traffic jams with road accidents. Sleet causes the breaking of trees and of electric or telephone wires.

Modern weather forecast predicts cold waves early and issues warnings to prevent traffic accidents.