Taking the local weather in Undheim into account is an important factor for planning your visit, especially if you plan to spend your trip by the pool. The hottest months are usually August and July, with an average temperature of 14°C, while the coldest months are February and January, with an average of 4°C. The rainiest months in Undheim are October, November, December and September, with each month seeing an average of 222 mm of rainfall.