A low shelf cloud sweeps over buildings at Brock University in Ontario.

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Preparing the 3D view

Preparing lighting and the first complete frame…

Model scale

Vertical dimensions ×20. cold slope 1:50. warm slope 1:150.

Section spans 600 km. Surface warm sector 120 km wide.

How to read these results

Play or scrub Process to follow the faster cold front. Slopes and speeds are prescribed; clouds are illustrative. A surface weather-chart line is the ground trace of a sloping boundary.

Fronts as wedges

Compare warm, cold and occluded fronts, and explain how the movement of contrasting air masses produces cloud and rain.

Drag to rotate. Hold Ctrl and scroll to zoom, or pinch on a touch screen.

Why it happens

A weather front separates air masses with different temperature and density. A colder air mass can undercut warmer air, while a warm front rises more gradually over cold air ahead.

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A cold front passes Brock University, St. Catharines, Canada. The cloud edge makes uplift visible; the front itself is a zone of contrasting air.

Try a comparison

Scrub Process to 0.70, where the surface warm sector closes. Continue and locate warm air above the meeting point.

Reading the result

The chosen front slopes and speeds illustrate their geometry; cloud shapes do not calculate rainfall totals.

A common misunderstanding

A front is a solid wall that keeps two air masses completely separate.

A front is a transition zone across which properties such as temperature and humidity change. Its slope and movement affect how air is lifted, with cloud and precipitation depending on moisture and stability. Mixing occurs, and real fronts have more complex shapes than a single dividing line.

Cases

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