It seems like as soon as the summer season officially ended, the Bay Area immediately started to heat up. That is certainly the case this year and this week. Fall started last Thursday and ever since we've been having a heat wave.
The wave hit its peak Monday with record-breaking heat. Although not officially, thermometers in San Francisco hit 100 in many places.
We expect another hot day Tuesday before we see some relief in the form of our ocean a/c sea breeze that should be kicking in by sunset. But before then, expect highs inland mainly in the 90s to as hot as 105 near Livermore and Morgan Hill.
The intense sunshine and lack of winds is also stirring up ground level ozone. That has prompted a fifth Spare The Air day for Tuesday - with the heaviest concentrations of ground level ozone for the East Bay, Tri-Valley and Santa Clara Valley.
As the sea breeze returns and low clouds build back on the coast, we'll see gradual and noticeable inland cooling into Wednesday and Thursday with temperatures dropping to near seasonal averages by the weekend.
The entire state of California has been in the grip of a heat wave since high pressure built over the West late last week.
Southern California has it even worse. Downtown LA recorded an all-time record high of 113 degrees Monday. The old record was 112 degrees on June 26, 1990.
It was hot enough in the North Bay Monday for a cooling center to open in Petaluma.
Fire danger is also a concern. Two fires broke out in the Napa and Marin area Monday. Both were contained quickly thanks to quick-acting firefighters.