In another alarming measure of California’s historic drought, the summer months this year were the state’s driest on record since 1895, when data-gathering for the government’s standard drought index began.

The monthly average dryness for July, August and September 2021 was -6.8 on the Palmer Drought Severity Index, which indicates extreme drought. Anything below -4.0 on the Palmer scale is considered “extreme drought.” A year with normal precipitation would fall between -0.49 and 0.49 on the scale, and an “extremely wet” year would land above 4.0.