Cold fronts move slowly across the landscape.

A squall line is a line of severe thunderstorms that forms along a cold front .

A warm front is found where warm air mass slides over a cold air mass

At stationary fronts the air masses move rapidly.

The temperature gradient or temperature difference across the front may decrease, so the air masses start to mix.

When a cold air mass takes the spot of a warm air mass, there is a warm front.

An occluded front or occlusion usually forms around a high pressure system.

The meeting place of two air masses with different characteristics is called a warm front.

A change in temperature over distance is called a temperature gradient.

As the warm air mass approaches, temperatures rise.