Other facts from our historical weather data: When is summer in Hagerman?The hottest season / summer takes place in June, July, August and September. Does Hagerman have a dry season? Yes, the months of February, May, June, July, August and September are very dry. Which is the warmest month in Hagerman? July has an average maximum temperature of 35°C (95°F) and is the warmest month of the year. Which is the coldest month in Hagerman? The coldest month is December with an average maximum temperature of 3°C (37°F). Which is the wettest month in Hagerman? December tops the wettest month list with 42mm (1.7 in) of rainfall. Which is the driest month in Hagerman? July is the driest month with 3mm (0.1 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.