After a period of cool weather last week, hotter-than-normal weather has returned to Southern California through Thursday.
Offshore flow and high pressure at the surface and aloft will bring well-above-normal temperatures through Thursday. Normal high temperatures are in the upper 70s and low 80s.
Through Thursday, expect high temperatures of 10 to 15 degrees above normal inland from the coast through the valleys.
Wednesday and Thursday will be the hottest when the offshore flow is strongest. Highs will range from the upper 80s and low 90s along the coastal plain, including downtown, to the high 90s in the valleys.
Some record high temperatures will be challenged Thursday.
It is likely to cool down noticeably Friday and over the weekend.
Dry and sunny conditions will continue in San Francisco for the official start to winter and the Christmas holiday.
Sunshine will return in full force for the weekend, the official start to winter, and Christmas in Los Angeles.
Big changes are on the way for parts of the Western and Central states late this week and into this weekend.
Similar to the days prior to Thanksgiving, the worst weather will focus on the days prior to Christmas as millions of travelers take to the roads and skies in the U.S. and southern Canada.
Warm air is forecast to surge into much of the eastern half of the nation by the weekend and will be accompanied by heavy rain and flooding risk in some locations.
Thunderstorms in parts of the South this weekend may become strong enough to threaten lives and property.
Galena, AK (2001)
A cold outbreak sent the temperature plummeting to 3 degrees below zero at Nantucket, MA and to 11 degrees below zero at Boston, MA
Central Illinois (1836)
Famous "Sudden Change" in central Illinois. Cold front at noon caused quick drop from 40 degrees to zero.