Front Cold — free printable diagram

What a cold front diagram shows

A front is the boundary between two air masses at different temperatures. At a cold front, advancing cold air meets warmer air and, being denser, pushes underneath and lifts it sharply. That steep lifting is what produces the tall clouds and the short burst of heavy rain a cold front is known for, and it is why the diagram is always drawn in cross-section.

What it is

The boundary where advancing cold air meets warmer air

What the cold air does

Undercuts the warm air and forces it to rise steeply

Cloud produced

Tall cumulonimbus

Weather

Heavy showers or thunderstorms over a narrow band

As it passes

Temperature falls, pressure rises, skies clear behind it

Map symbol

A line with triangles pointing the way it is moving

• Cold air is denser than warm air, so it cannot ride over the top. It pushes in underneath, and the warm air has nowhere to go but up — the mechanism the whole diagram exists to show.
• Steep lifting means tall clouds. Air forced up quickly cools quickly, so the water vapour condenses into towering cumulonimbus rather than flat layers.
• A warm front is the mirror image: there the warm air slides gently up over the cold air ahead, giving layered cloud and several hours of steady, lighter rain.
• So the rain belt at a cold front is narrower and heavier, and at a warm front wider and gentler. Comparing the two cross-sections side by side is the standard way to teach both.
• An occluded front forms when a cold front travels faster than the warm front ahead of it and catches up, lifting the warm air clear of the ground altogether.
• In a depression the fronts usually arrive in order: the warm front first, then the milder warm sector, then the cold front with its heavy shower and the clearance behind it.