Hello. I'm considering a trip to Europe in September or October. Right now I'm thinking of visiting one of the following: Rome, Vienna, Norway, or Poland. Would any of these destinations be ruled out that time of year due to weather or some other factor?

Thanks.

Norway IMO - days getting short - cool - Rome would have the best weather if liking to sit at outdoor caffes, etc. Europe above Alps can always be wet and cool but in cities tolerable. Norway is also very expensive compared to others.

Thanks, PalenQ. Any other thoughts?

Well hard to say unless we know your interests - why have you chosen those places and all are great - but too general a question. How much time do you have?

I have a long mental list of places I'd like to visit. I've been thinking that instead of worrying about what order to visit I'll just start visiting. For this trip I'll have five or six days. Vienna is where I wanted to go since I've never been. But, then, I've never been to Ravenna and I think I'd like to see it. Norway and Poland are just two other places on my mental list.

Norway is a big country. Where were you thinking of in Norway? It is also an expensive country of course.
Poland is a bigger country. Where where you thinking of in Poland?
If you really want to go to Vienna then go to Vienna. Five to six days is not enough to even scratch the surface of Norway or Poland.

I'd suggest Rome because of the weather and it has so much to do for several days - can take day trips to many neat places but if Ravenna maybe fly into Milan and take train to Ravenna and then train to Rome for 3-4 days. Trains are great everywhere you go and easy to use base cities like Vienna and visit also some neat places. For lots on trains and where to go by them from base cities, check www.seat61.com; BETS-European Rail Experts and www.ricksteves.com. But, no one can say which place is best - I am recommending Rome because of weather - but you still are all over the map.

The weather in Vienna is nice in September and decent in October. Lots to see in Vienna but maybe add Salzburg to your itinerary. Rome weather in the fall is generally fantastic. and there are many day trips from there, Ostia Antica, Orvieto, Tivoli, for example. Sounds like you’ve been to Rome before, so you might consider some spots a little further away. You you can reach Tuscany, Umbria, and even Naples, Pompeii and the Amalfi coast easily from Rome.

Save Norway for a visit in the summer. Rome is nice in mid to late October as is Sicily.

Any large city is tolerable even in the worst of weather and if Vienna is your goal great. It may be cool and rainy never know - anyway what do you (OP) think

I think Poland, especially Krakow, is a great idea for September or October. We visited Krakow at the end of October and really enjoyed it. The sidewalk cafes use heaters, so we were able to sit outside sometimes for drinks. We did a lot of outdoor sightseeing in addition to seeing indoor sites, such as museums, churches, etc. We had nice weather, sunny and cool, perfect for sightseeing. it rained one day, the day we visited Auschwitz, so that was appropriate for such a depressing place. We also visited the salt mines, which are amazing. I prefer cool, crisp weather for sightseeing. I think we wore winter coats but I am not 100% sure about that. It was late October.

You might want to go to your local library and browse some guidebooks, most of which will have a section on "when to go."

Or even better, save the trip to the library and simply google "best time to visit Norway", for example. You will get very detailed information on crowds, weather, events, etc.

Vienna is generally lovely in September for a number of reasons, including more reliable weather. The large tourists crowds have also dwindled, so I will venture beck into the Inner Stadt to catch up on any exhibits that opened during the summer. The vineyards around the city are bursting with grapes that make the vineyard wandering weekend particularly pleasant (Wien Weinwandertag 2018 is 29 and 30 September this year); and the cafes and heurigers almost always have an empty table. If you're a morning person there is excellent lighting in the early hours for photographs, too.

This photo was taken early on a mid-September morning.

To each his / her own! I never consider a trip to a library wasted, and I far prefer guidebooks to googling when choosing destinations. JMO

I used to go to library and photocopy sections of places I was going to from several guides to take with me and then have benefits of a guidebook but no heft and several different angles.