What will happen if it does not rain for a long period of time?

A lack of rain over a long period could result is a drought. If a drought continues for a very long time (especially in hot countries) food crops could shrivel in the fields, no seeds could be sown to produce a future crop, wild and farm animals could die, the top soil could dry enough to become dusty and prone to be blown away by a wind. People and animals could be forced to migrate to find water.