will depart on 27th december morning from LA and want to reach SFO on 30th morning.

i want to see big sur and yosemite.

Should i fly to monterey and visit big sur and next day proceed to yosemite and then to SFO- or fly to fresno, visit yosemite and next day drive to monterey and then on to SFO.

I can drive from LA also.

Since it will get dark early should we stay inside the park or stay at el portal or groveland.

I will have to take snow chain from mariposa or groveland before i get into the park.

I would do the lovely drive up the coast, it only takes a few hours (or you can stop and enjoy Santa Barbara or Paso Robles). The 27th will be a hellish day at the airports so it won't really take you much longer just to drive it. As for your rental car, you'll have to find one that allows you to put chains on the car, I'm not sure how lenient they are about that.

Good point about the airports being a mess on the 27th, but so will the freeways-- maybe worse. Plus, depending on the weather, the 1 could be a rough go.

I think I would fly to Fresno, visit Yosemite, then head to the coast to see Big Sur, finally head to SF on the 30th on Hwy 1 if weather permits or 101 if the weather is bad.

If I were to make this trip at the end of December (which I wouldn't), I would start by driving as far as San Luis Obispo on Highway 101, and then drive as far as Monterey on Highway 1. This is a beautiful trip and there is much to see and do along the way.

From Monterey I would drive to Yosemite and I would definitely stay at Yosemite Lodge at the Falls (a great base for seeing the park).

Then I would drive to San Francisco.

Under normal conditions, the drive from LA to Monterey is about 325 miles (6 1/2 hours without stops), Monterey to Yosemite is about 200 miles (4 1/2 hours), and Yosemite to San Francisco is about 200 miles (4 hours).

HTTY

I don't think the freeways will be worse on the 27th and in fact might be lighter. Many people take the week off between Christmas and New Years plus schools are not in session. If people have to be back to work on Dec 27, they will be driving home on the 26th.

Your time is short but driving is the best way to see the coast. I would definitely check with the rental car companies about chains. Another consideration is what the drop-off fee will be for your car. I have found that some smaller airports don't have one way rental. The problem with flying into either Fresno or Monterey is that the fare can be very expensive although right now they have one way tickets from LAX for $130. If you decide to fly I would book it right away becasue I have seen flights from LAX to Fresno being as much as $400.

You will have to keep an eye on the weather. About 5 years ago, my DD, her boyfriend and I drove from So. Cal to SF, spent a few days there and then were going to drive home via Big Sur. It had been raining and Highway 1 was closed due to a mudslide.

Christmas falls on Saturday this year, so most people will have Monday the 27th off returning from their holidays. And the New Year's crowd will be heading to their vacation destinations.
We were looking into our preferred vacation rental over the holidays in Cambria and they are booked. And so were other rentals I would have settled for. Last year, in November they weren't. That's not even a 'go to' place like Lake Tahoe. I think there are going to be a lot of cars on the road this year but the airport probably won't be any better on the 27th.
OP start booking!

When Christmas falls on a Saturday, the friday is a holiday for most people, not the Monday. I don't know anybody who's employer is giving Monday the 27th as a holiday. I could be wrong.

I would either drive the coast all the way or see Yosemite, not both. I'd stay in Yosemite, not outside the park, but I'd probably pick the coast in late December.

When Christmas falls on a Saturday, the friday is a holiday for most people, not the Monday. I don't know anybody who's employer is giving Monday the 27th as a holiday. I could be wrong.
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Friday is Christmas Eve, businesses close early. I don't know of any 'professional business' that works on a Saturday or Sunday. I know that's our paid day- that's all I care about.
Still, as I thought about the last several years visiting NO.Cal family/vacationing over those holidays- it doesn't really matter what days you travel, so is everyone else. Lots of people use the season holiday for a lot of different reasons. In general, people try to arrive before Christmas for that week or they're doing after Christmas for New Year's.
Just from my inquiry- I think road travel is the ticket instead of international.
Of course, I could be absolutely wrong like anyone else.