Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from San Diego to Mahé as you normally would.
In terms of precipitation, rainfall in Mahé ranges from 2.8 - 15.0 inches per month. January is typically the wettest month, when rainfall can reach 15.0 in. August is typically the driest time to visit Mahé when rainfall is around 2.8 in.
If weather is an important factor for your trip to Mahé, use this chart to help with planning. For those seeking warmer temperatures, March is the ideal time of year to visit, when temperatures reach an average of 82.4 F. Travelers looking to avoid the cold should look outside of July, when temperatures are typically at their lowest (around 78.8 F).