High pressure is firmly in place across The West but its grip is slipping.
I think the interior faces 2 more days around 100. Currently the National Weather Service has a heat advisory thru Sunday at 9pm for the interior of both SLO and Santa Barbara counties but Monday looks similarly warm. Tuesday more significant cooling takes place.
The reason for the heat is that ridge of high pressure, it has slowed the onshore flow and also compressed the marine layer significantly. This means only a few places right near the ocean are seeing 60 degree highs, even the near coastal valleys are in the 70s and 80s.
We'll see more night and morning clouds at the beaches and those near coastal valleys but not inland over the next several days.
More cooling takes place Tuesday thru the balance of the work-week when a trough digs into the Pac NW increasing the onshore flow and lifting the marine depth back into the interior valleys.
Interestingly there is a tropical system likely impacting the Baja Tuesday and Wednesday this week. This will stream clouds and allow for some thunderstorms in far Southern and Eastern California, but I think we are too far away and SW steering flow should keep all of that away from us here on the Central Coast.