Webseasonal rainfall charts for the main site. Historical cumulative and daily rainfall totals back to the 1997/1998 season when the automated rain gauge was. Webcalifornia’s new water year began oct. 1, 2024 and ends sept. Webcalifornia water watch, hydrology update and drought status. Precipitation % of average for full water year through september 30th: Webas shown in figure 1, for the october 2023 to august 2024 period, nearly all areas of the state have had near average precipitation accumulation except for areas in.