Or they ignore the past. There was a 2 year drought in Ca. in the late 1800's where it did not rain for two seasons. The Yuba River dried up, and most of the cattle in the state died because of it.
Somewhat related because my favorite band recorded a song about it:
Charles Hatfield studied pluviculture and began to develop his own methods for producing rain. By 1902 he had created a secret mixture of 23 chemicals in large galvanized evaporating tanks that, he claimed, attracted rain. Hatfield called himself a "moisture accelerator".
In 1904, promoter Fred Binney began a public relations campaign for Hatfield. A number of Los Angeles ranchers saw his ads in newspapers and promised Hatfield $50 to produce rain.[citation needed] In February, Hatfield and his brother Paul built an evaporating tower at La Crescenta where Hatfield released his mixture into the air. Hatfield's attempt was apparently successful, so the ranchers paid him $100. Contemporary weather bureau reports described the rain as a small part of a storm that was already coming but Hatfield's supporters disregarded this.
Hatfield began to receive more job offers. He promised Los Angeles 18 inches (46 cm) of rain, apparently succeeded, and collected a fee of $1000. For this effort, Hatfield had built his tower on the grounds of the Esperanza Sanitarium in Altadena, near Rubio Canyon.
In 1906 Hatfield was invited to the Yukon Territory, where he agreed to create rain for the water-dependent mines of the Klondike goldfields. The Klondike contract was for $10,000, but after unsuccessful efforts, Hatfield slipped away, collecting only $1,100 for expenses. This failure did not deter his supporters.
In 1915 the San Diego city council, pressured by the San Diego Wide Awake Improvement Club, approached Hatfield to produce rain to fill the Morena Dam reservoir. Hatfield offered to produce rain for free, then charge $1,000 per inch ($393.7 per centimetre) for between forty and fifty inches (1.02 to 1.27 m) and free again over fifty inches (1.27 m). The council voted four to one for a $10,000 fee, payable when the reservoir was filled. A formal agreement was never drawn up, though Hatfield continued based on verbal understanding. Hatfield, with his brother, built a tower beside Lake Morena and was ready early in the New Year.
On January 5, 1916 heavy rain began—and grew gradually heavier day by day. Dry riverbeds filled to the point of flooding. Worsening floods destroyed bridges, marooned trains and cut phone cables - not to mention flooding homes and farms. Two dams, Sweetwater Dam and one at Lower Otay Lake, overflowed. Rain stopped on 20 January but resumed two days later. On January 27 Lower Otay Dam broke, increasing the devastation and reportedly causing about 20 deaths (accounts vary on the exact number).
Charles Hatfield and the 1916 flooding at Lake Morena is the subject of the song "Hatfield" by the band Widespread Panic.
https://en.wikipedia.org/wiki/Charles_Hatfield