Hydroclimate Report Water Year 2020

Water Year (WY) 2020 continued to demonstrate the climate change narrative of greater variability and more extremes.
In both precipitation and temperature, there were new extremes with a very dry February and very hot end to the water
year. Late fall precipitation onset continued with the first significant storm of the year arriving in late November. The
WY ended with 67 percent of average precipitation statewide and 62 percent of average in the Northern Sierra. For runoff,
the Sacramento Basin had 66 percent of average April-July streamflow while the San Joaquin Basin had 58 percent of average. Peak statewide snowpack was 62 percent of average reaching that point in early April with a late season storm providing some offset to the winter’s dryness. February was one of the big stories of WY 2020 with record low precipitation. In a year of extremes, August and September also contributed record warmth for the month including a 130-degree Fahrenheit reading at Death Valley on August 16, 2020. This observation, if verified by the World Meteorological Organization, would be one of the hottest daily temperature maximums recorded on Earth. Several cities set new records for days above 90 degrees as well.