While this past winter has offered quite a few cold mornings, the trend over the past 100-plus years has been a warming winter story. The graph below shows how we having been warming from December to February since 1880. In fact, 2008 was the last winter average where temperatures were considered below average.
In the second graph below, we focused on morning low temperatures. You can see the trend is also warming over the past several decades with just a few dips below average. The last time morning temps ranked below average was 2013.
The trend of warmer winter temperatures is also what we are seeing over the Sierra. This means more rain for the mountains and less snow. All of this is contributing to a lower snowpack, which is vital to California’s water supply.
You can find out more about how the Bay Area climate is changing in a series of stories the Microclimate Weather Team worked on.