Features on the surface weather chart indicate likely rainfall patterns as well as temperature distribution and wind strength. While cloud can exist without rain, the opposite is not the case.
Clouds form by the condensation of water vapour through cooling.
Convection , which may be caused through air mass instability. It may be initiated by warming of low-level air, forced ascent over mountainous country, or dynamic causes associated with severe weather systems. Cumulus clouds often form as a result of convection. The most exceptional forms are often associated with severe thunderstorms and occasionally, tornadoes. Cumulonimbus, for instance, may reach altitudes above 15,000 metres.