Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from San Luis Obispo to Hong Kong as you normally would.
In terms of precipitation, rainfall in Hong Kong ranges from 0.8 - 15.4 inches per month. June is typically the wettest month, when rainfall can reach 15.4 in. January is typically the driest time to visit Hong Kong when rainfall is around 0.8 in.
If weather is an important factor for your trip to Hong Kong, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 84.2 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 60.8 F).