Other facts from our historical weather data: Which is the warmest month in Cerritos? February has an average maximum temperature of 26°C (79°F) and is the warmest month of the year. Which is the coldest month in Cerritos? The coldest month is September with an average maximum temperature of 25°C (77°F). Which is the wettest month in Cerritos? July tops the wettest month list with 1187mm (46.7 in) of rainfall. Which is the driest month in Cerritos? January is the driest month with 626mm (24.6 in) of precipitation. No idea where to travel to this year? We have a tool that recommends destinations based on your ideal conditions. Find out where to go with our weather planner.