2013: Strong offshore winds peaked at 86 mph at Fremont Canyon.
2007: A snow storm on 12.8 and on this day was nothing unusual except in the San Jacinto Mountains 17" fell in Pine Cove.
1998: Santa Ana winds started on this day and ended on 12.10.
Gusts reached 101 mph at Modjeska Canyon, 93 mph at Fremont Canyon, 52 mph in Santa Ana, and 83 mph in Ontario.
Trees and power lines were downed, vehicles overturned, and damage was done to property.
1995: A powerful storm system moved through the Bay Area with widespread winds over 40 mph with a max wind gust to 135 mph.
These strong winds caused major damage to the Arboretum and many trees in Golden Gate Park.
1985: Strong storm winds of at least 35 mph hit the San Diego County coast.
Several boats in Mission Bay were capsized.
Numerous trees were downed causing power outages, one on a car on Hwy. 163, another on a parked car in Coronado.
1982: Heavy rain in eastern San Diego County that started 12.8 ended on this day.
Flooding resulted, and it was disastrous in Ocotillo.
1978: Highest barometric pressure ever at Fresno tied, 30.64" (also set on February 1, 1916 and December 25, 1932).
1972: The morning low at Portola was -28° F and at Truckee it was -22° F.
The morning low of –16° F at Reno, NV, remains the record low for the month of December at Reno, NV.
1972: Lowest ever in December, Lodgepole (Sequoia NP) had -16° F, and Grant Grove, -4° F.
1963: Heavy snow fell in the mountains.
Five were killed and six were injured.
Highways were blocked.
1960: It was -14° F in Big Bear Lake, the lowest temperature on record for December.
1938: It was 92° F in Escondido, the highest temperature on record for December.
1918: 12" of snow fell at Tahoe City (west shore Lake Tahoe).
1898: A waterspout was observed off Mt. Soledad – La Jolla and Pt. Loma for 10 minutes.
This was considered the first such thing in history on this stretch of coast.
Heavy rain caused the railroad to be washed out and a half mile of it was covered in mud in Rose Canyon, near Pacific Beach.
A trestle in Chollas valley was washed out, causing "several hundred dollars" in damage.
Source: NWS San Francisco/Monterey, Hanford, Reno, Las Vegas, & San Diego