This is proving to be the coldest December in San Luis Obispo County, California, since 1971, says local weather expert John Lindsey. And December 1971 was the coldest December on record.
The average high temperature for the month based on record-keeping that started in 1948 is 64.5 degrees, Lindsey said. So far this month, the average high has been 61.5 degrees.
The average low this month has been 37.4 degrees, well below the historical average of 42.1 degrees. If the highs and lows are put together and averaged, this month has had a temperature of 48.5 degrees, far off the historical average of 53.3.
Thanks to Randall Tillotson for this link