Droughts can occur at any time during the year. A drought is usually determined by the lack of precipitation that falls during a period of time, but it can take a long time for its effects to be noticed.
Droughts are usually noticed the most during periods when a region receives the majority of its precipitation. This varies from place to place. One region may get most of its rainfall in the spring, while another receives most of its during the winter. A drought can take weeks, months, years or even decades to notice.
A drought is a period of drier-than-normal conditions that results in water-related problems, such as a lack of drinking water, crop failure and lower water levels in rivers and streams. The term drought is very subjective and can mean different things to different people. To a farmer, a lack of water during the cultivation of crops is a drought, even if it only lasts a couple of weeks. Meteorologists define a drought as less than average precipitation during a given period of time, regardless of the season. Droughts are very common. They can be brief or long-lasting, such as a drought in California that spanned from 1928 to 1937.