School and university holidays make the peak summer months the most popular time to visit Berlin, and the city always puts on a good show with plenty of outdoor events to enjoy. The good weather also lets Berlin open its doors, spill onto sidewalks and cram the beer gardens of its wonderful parks, although things can be wearingly hot. Highs can easily hit a of high 90ºF (32ºC). Thankfully evenings cool off considerably and summer is also the rainiest time in Berlin, so it’s certainly worth packing something warm for after dark and some light rainwear for sightseeing. Summer crowds can also get a bit wearing, particularly at key sights such as the Reichstag, where you can wait well over an hour to enter. Summer is also the most expensive time to plan a Berlin vacation—around 30% higher than in winter, and room availability can be an issue, particularly during major events, although the city’s large stock of accommodations means you shouldn’t have any problem finding something suitable, even if it’s not your first choice. For this, you’d probably have to book at least a month in advance.
To avoid Berlin’s hottest days and greatest visitor crowds, the shoulder season is ideal, and you may find small discounts on hotels and airline seats. Almost all of the summer possibilities are available, too, though unpredictable weather can temporarily cast a shadow over some plans. You can expect highs of around 77ºF (25ºC), with the occasional frosty morning, and sunshine some 6 hours per day. You’ll need to pack for this with a range of layers more or less for every eventuality. September is perhaps the perfect time, away from the sweaty excesses of summer and the bustle of visiting German school groups, yet with superb and reliable weather.