How is weather caused?

Weather processes such as wind, clouds, and precipitation are all the result of the atmosphere responding to uneven heating of the Earth by the Sun. The uneven heating causes temperature differences, which in turn cause air currents (wind) to develop, which then move heat from where there is more heat (higher temperatures) to where there is less heat (lower temperatures). read more

Weather systems in the mid-latitudes, such as extratropical cyclones, are caused by instabilities of the jet stream flow. Because the Earth's axis is tilted relative to its orbital plane, sunlight is incident at different angles at different times of the year. read more