San Francisco is still a month away from their normal hottest day of the year! Conversely, most other cities around California and the nation are well past their normal hottest day, which typically occurs about a month after the Summer Solstice. But a few locations, especially along the West Coast, wait until August and even September to peak. And San Francisco is certainly the latest of any major United States city by not reaching its normal highest maximum temperature of 70.4 until September 24t. Source: http://ggweather.com/normals/daily.htm