Northbound
Advantages: Some drivers experience a greater sense of safety here on the inside lane of the highway with the inland cliff rising on your right and a lane between you and the drop-off to the ocean.
Disadvantages: The majority of pull-outs are on the ocean side of the road, so you'll need to cross over against traffic.

Southbound
Advantages: You'll have spectacular views and easy pull-outs.
Disadvantages: Ever see Hitchcock's movie Vertigo? There'll be nothing between you and that 500 foot high view except thin air.

This region of California has a Mediterranean climate: mild, but wet winters and dry, mild-to-hot summers.

Rainy Season
The rainy season lasts from November to April.

Advantages: Much less traffic allows you to frequently feel like you have the road to yourself. There’s also less fog. On a clear day, you'll swear you can make out Hawaii on the horizon.
Disadvantages: Washouts are frequent during this time, meaning you may need to make detours or abandon the trip entirely. Check with CalTrans on road conditions.

Dry Season
Advantages: Little fear of washouts and predictably dry weather.
Disadvantages: Heavy traffic, especially on weekends. The coast is more likely to be covered in fog, obscuring views.