Weather

The science is pretty settled. But while we should all prepare for more weather fluctuations as a result, I still think your best bet is to look at one of the various weather sites and compare the past 2-3 years.

The science may be settled on the fact that temperatures are rising, and on the fact that rise is caused primarily by an increase in CO2 emissions in the atmosphere especially due to human activities, in particularly since the Industrial Revolution. The climate however has not changed in drastic ways yet. In the last 50 years the average temperatures in Rome have increased only about 1.5 degrees Celsius. That means that the average high temperature at the end of May is now about 25 degrees Celsius (77 F) instead of maybe 23.5 degrees C (74 F), 50 years ago. Rain precipitation has not registered a significant change since 1950, but end of May/June is generally drier than autumn or spring, so you don’t have to worry too much about rain, but have a pocket umbrella just in case for the occasional thunderstorm.
There is no way to know now what the weather will be at your destination in 6 weeks, but weather forecasts tend to be reliable about 7 to 10 days forward, so check any weather app just before you depart, and you should have a better idea of what to expect. One thing I could safely bet on, even now, is that in none of the cities you are visiting there will be snow.

I like to look at actual, day-by-day weather statistics in recent years to get an idea of the range of conditions I may run into. There are quite a few websites where you can find that information displayed in different ways. I've gotten used to using timeanddate.com.

Weather in Florence -- May 2025

Weather varies a lot from year to year, so it's important to look back over multiple years. I usually go with five years. Use the pull-down box at the right, just above the graph, to change the month and year displayed. (You'll want to do that so you can see June as well as May.)

Use the Search box at the upper right to change the city for which data is displayed.

I wouldn't trust the history of the past few years. At the end of May 2019 it was cold and rainy in Florence. In May 2018 it was unusually hot. If in May 2019 I had based my prediction (and clothes packing) on the previous year or two, I would have frozen. And by the way that unseasonably cold May 2019 was followed by a June with temperatures in the 100s F just a week or so later.

So the general expectation should be that high daily temperatures at the end of May or early June should be in the high 70s/low 80s, but be ready for unusually odd weather, therefore checking the forecast just before going is the best strategy.

I like to know how bad it could be. The chart for Florence's weather in May last year shows high temperatures of 86, 88 and 90 F on the last three days of the month. And it was 84 and 86 on May 1 and 2, respectively.

I'd call the situation in June 2025 "grim".

Florence weather -- June 2025

I should perhaps mention that I take very long trips. As I'm preparing my packing list, the weather forecast is reliable for only a small percentage of the entire trip. Therefore, I need to look at what has been happening in recent years.