The weather in October in Bologna is much like the weather in the northeast of the US at that time of year, except it's more likely to rain. Bologna is actually on the Po plain, which is both hotter in summer and colder in winter than where we live, near the Adriatic. However, spring and autumn at sea level are much the same in all the temperate zones of the world. (In the mountains, which we can see from our house, there is often snow already in October.)

Wow! I've always wanted to see the birthplace of the ocarina!

I had checked the timetables for the Certosa di Pavia yesterday and didn't see any connections that were much less than two hours, and even those were a bit later in the morning than I would want to set out on a day trip. I just rechecked and don't see any connections anywhere near as convenient as what Frencharmoire indicates. All of them go to Milano Rogoredo, either directly or with a change at Milano Centrale. Catching a Frecciarossa from Bologna directly to Rogoredo, the fastest connection is 1 hr 49 min.

I just looked. Are you using the Trenitalia website? I see Bologna/Rogoredo/Pavia as a bit more than 90 minutes, then you would need a taxi of course if the Certosa was the target. Taking an 11.30am train, you'd get to Pavia in good time for lunch, and could see the Certosa after lunch. I don't recommend this, especially if one has an opportunity to go from Milan, but I don't find it more daunting than going to Ravenna from Bologna (although Ravenna is much more rewarding -- almost too rewarding for just a day trip).

Buses from Pavia are the best way by public transit to the Certosa -there is a train station but about a mile or so away.

Thank you for all the great info on Bologna and Certosa and Marradi and the weather. "Voi" have talked me into Certosa, I will go there while in Milano. Grazie mille!

One of favorite places in Italy is Sicily. The antiquities are spectacular as is the scenery. The food is wonderful and there are many influences over the centuries.