Zagreb in December

April through October gives you the best of Zagreb without the coastal crowds. Spring (April-May) brings perfect walking weather and outdoor café season - temperatures hover around 18°C. Summer (June-August) can hit 30°C, but the city doesn't empty out like coastal towns. This is when outdoor festivals like INmusic happen in June. Fall (September-October) might be ideal - warm days, cool evenings, and the city's cultural season kicks into high gear. Winter isn't terrible if you're into Christmas markets and cozy indoor scenes, but expect grey skies and 2°C temperatures. The Advent Market runs December through January and transforms Jelačić Square into something magical. Avoid late November - it's cold but not festive yet.