There seems to have been some strange climate change at work across San Francisco since 2000. Daily minimum temperature records are very difficult to achieve at the airport in this the 21st century but still quite common in downtown San Francisco over the past 15 years.
Number of Daily Temperature Records since 2000 in San Francisco using 70-year period of record from 1945-2015:
# Min Records # Max Records
Downtown 104 102
Airport 9 108
