August in Northern California
 

I will be traveling to Northern California visiting family. We will be spending the first four days with family in Lake Tahoe and Sacramento. We have 5 more days and would like to go to Carmel, Monterey, San Simeon, Santa Barbara. Any suggestions on itinerary or if we have enough time to visit all these areas? We would like to travel the coast and are open to any other sites as well! We are flying into SF but are flexible on a city to fly out of if it makes sense to travel south and leave from there.

Thanks!

It,s possible to get to all these areas in 5 days but you will be driving at least half the day between each place. I would suggest booking two nights in the Monterey or Carmel area, and drive down Hwy 1, Big Sur, and stay one night in the town near Hearst Castle, then two nights in Santa Barbara. That way you would have some time to actually see sights. You could fly out of LA in the later afternoon, perhaps. Once you have a plan, make motel or hotel or airbnb resevations right away, because this is high season, and the nicest places are booked quickly. You could be better off if you can time your hotel/motel stays between Monday and Thursday nights.
It will be a bit of a rushed 5 days, but still enjoyable.

I agree with all of NoCaliGal's suggestions. You also might want to look into flying out of Santa Barbara airport. By doing so you could avoid the irritation and stress of driving LA freeways. Also the smaller airport would be less stressful than the massive and crowded LAX.

Some highlights not to miss: Point Lobos, coastal walking and bike trail in Pacific Grove, and the Monterey Bay Aquarium.

One more thing: at times in August, the CA coast can be windy and chilly due to frequent ocean fog. So bring sweatshirts and jackets.

Will you be renting a car? If so, flying out of a different airport may incur rather large drop-off fees.

Santa Barbara is really not Northern California. The hotel rooms are quite expensive. With only 5 days, I wouldn't go any farther south than Big Sur.
Plan on returning the rental car where you rented it.
Flying to San Jose, Oakland or Sacramento may be a cheaper option since you are headed for Tahoe first.