I am thinking about traveling south from San Fran on Hwy 1 - what about traffic in the summer on a weekend?

I am up in Pleasant Hill and want to see some sights on my way back to San Diego. Was thinking about spending the day in San Francisco and then traveling down Hwy 1 to see the coast. Thinking of sticking on the 1 to Monterey, Morro Bay and all the way to Santa Barbara. Is this a good idea, or awful because it is summer and there are a million other people thinking of this too? THANKS FOR INPUT