Norwegian Cyclone Model

The Norwegian cyclone model, so named to honor the Norwegian meteorologists who first conceptualized the typical life cycle of cyclones in the 1910s and 1920s, presents the evolution of a cyclone. In this model, there will initially be a boundary, or front, separating warm air to the south from cold air to the north. The front is often stationary. (Left - Overhead view; Right - 3D view)

Norwegian cyclone model initial stage - overhead view Norwegian cyclone model initial stage - 3D view

A wave on the front will form as an upper level disturbance embedded in the jet stream moves over the front. The front develops a "kink" where the wave is developing. Precipitation will begin to develop with the heaviest occurrence along the front (dark green).

Wave forms on front - overhead view Wave forms on front - 3D view

As the wave intensifies, both cold and warm fronts become better organized.

Wave intensifies - overhead view Wave intensifies - 3D view

The wave becomes a mature low pressure system, while the cold front, moving faster than the warm front, "catches up" with the warm front. As the cold front overtakes the warm front, an occluded front forms.

A mature low pressure system - overhead view A mature low pressure system - 3D view

As the cold front continues advancing on the warm front, the occlusion increases and eventually cuts off the supply of warm moist air, causing the low pressure system to gradually dissipate.

Dissipating stage of cyclone - overhead view Dissipating stage of cyclone - 3D view

Next: Precipitation