Warm fronts move slowly and often bring long periods of steady gentle rain.

The longer version

Along a warm front, the advancing warm air is lighter than the cold air ahead of it, so it cannot push underneath. Instead it rides up over the colder mass along a very gentle slope, rising gradually across hundreds of kilometres over the course of a day or more.

That slow, widespread lifting produces a broad shield of cloud that thickens and lowers as the front approaches, giving long periods of steady, gentle rain rather than sharp downpours. Since the slope is so shallow, the whole change takes many hours, and temperatures rise noticeably once the front has finally passed.

Where this entry sits

Clouds, wind, rain, and storms shape daily life in ways that most people barely notice. This collection explains snow, lightning, rainbows, the turning seasons, temperature, the instruments forecasters rely on, and scraps of old weather lore. The full list sits on the Weather and Climate page, where every entry is listed in order.