GAS tour

I did the Berlin, Prague & Vienna tour with additional days in Salzburg and Munich. Not exactly the same but similar. I went in June last year and the weather was perfect, mostly mid-70s during the day and only two rainy days out of 25.

We did it in mid September, which meant the tour was in Munich during Oktoberfest time which was a real treat. For us the key point, however, was the weather in the mountains (i.e., Switzerland) which was nice and warm in September that time. It's always a gamble in the mountains.

June is not a bad time to go. We took that tour in August and the weather was very nice. Of course, in the mountains the weather can be iffy any time of the year.

I’m glad to hear that the weather was good for each of you, which gives me a few months to pick from. It looks like an interesting tour, so I’ll give it some more thought.
Thank you!

We also took this tour in Sep (17-30, 2022), for the same reasons Stan referenced. September is the calendar month with fewest number of days with rain, statistically, in Berner Oberland; and we wanted to increase our odds for favorable hiking conditions. It worked, local conditions were stunning; however the RS group ahead of us had their entire Mürren stay under inclement weather (acc to hotel staff)... so you never know. This timeline syncs with opportunity to enjoy Oktoberfest during the festival's second week, if that's something which appeals to you. Vienna, where the tour ended, was absolutely beautiful in early-Autumn (still shirt-sleeve) weather. Such a schedule is considered 'off-season', if there is still such a thing, with fewer crowds than June/July when kids are out of school. Even Hallstatt was less than full, a relief after seeing some of the videos on YouTube.

This is a wonderful tour! I'd vote also with either June or mid-late September. I went the last week of August and hit a heat wave which was miserable in several places including where I started, which was Paris. I took this tour mainly for the 3 nights in Muerren which were fabulous. Oh my...even as a person that lives where I can see mountains, the Lauterbrunnen Valley is exceptional.

Here is my TR from 2016 although the tour itinerary has changed slightly. Mine started in Trier, yours starts in Cologne so just ignore my Trier comments and it's about the same. The clothing and weather sections still would work for informational purposes.

https://community.ricksteves.com/travel-forum/tours/trip-report-8-27-16-gas-tour

I was in Austria last year end of September and it was much warmer than I thought, almost uncomfortably so.

Damn that Al Gore!

I took a GAS tour several years ago (not with RS) and I went in September and it was perfect - most days were warm and sunny but not hot and evenings were cool. Only had one day of rain in 2 weeks and that was in Switzerland.

Thanks everyone. This will all be very helpful when I get ready to plan that tour. Fall is a nice time to travel, and I’ll definitely take all your suggestions into consideration.
Many thanks. I’ll probably be back with more questions at some point!