Other facts from our historical weather data: Which is the warmest month in Holt? July has an average maximum temperature of 13°C (55°F) and is the warmest month of the year. Which is the coldest month in Holt? The coldest month is December with an average maximum temperature of 4°C (39°F). Which is the wettest month in Holt? February tops the wettest month list with 277mm (10.9 in) of rainfall. Which is the driest month in Holt? June is the driest month with 117mm (4.6 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.