We’re planning on the BOE21 in 2024 but can’t decide on April or October. I’d prefer the latter but think that packing will be less or a challenge with the thinner/lighter clothes for spring, but I think we’d prefer fall. This will be our first RS tour so we welcome any and all advice and/or suggestions.
For me, the difference in wardrobe between a spring trip and one in the fall amounts to one Patagonia Nanopuff jacket and an extra long-sleeve merino shirt/sweater for October. Otherwise, I take the same pants, tops, lightweight fleece or cardigan, and rain jacket for both trips.
The nanopuff packs into a gallon ziplock which I compress down to less than an inch if thickness, and I slide it into the back panel pocket of my roller bag. I hardly know it is there but it is available if needed.
If you look at the weather charts under “what to expect” for that trip, you will see only 1-2 degrees of difference in average highs and lows for the months of April and October, and a slightly greater numbers of rain in October (20 vs 18 for April. Note that day are. Bit shorter in April.
The days will be a great deal longer in April, especially if you aren't heading out at the very beginning of the month. That matters tremendously to me, but perhaps not at all to you.
Time of the month would be a significant factor for me. I don't like chilly weather, and I like chilly, wet weather even less. I don't take trips north of the Alps in April or early May. By the time October rolls around it's getting dark early enough that I'm ready to come home.
The rain pattern varies. Some areas get more in the spring; others, in the fall. The climate-summary charts in Wikipedia's entries for major cities usually include some monthly-average precipitation statistics. I find those helpful. The temperature data is not adequate for me since it's just average highs and lows. In many cases those averages (this applies to precipitation as well) are for a period ending in either 2000 or 2010, so they are not really up to date.
I like to look at the actual, day-by-day, historical weather statistics available on the website timeanddate.com. The thought in the back of my mind is "How bad could it be?" and averages do not answer that question. I'd check out the April weather in Amsterdam and the October (or November if the tour ends then) weather in Paris for the most recent five years. Both of those cities can be chilly and damp.
I took a winter trip to Rome and points south this year. I was very lucky to have days with high temperatures mostly in the upper 50sF or 60sF. But it often didn't get up to 40F until 11 AM or later.
There are some tradeoffs to consider:
-Possibly better temperatures on the Italy portion of the trip. How heat tolerant are you?
-The ability to go a day or two early (which you should do anyway, lol) and visit Keukenhof Gardens which are spectacular
-The possibility that hiking in the Lauterbrunnen area may be curtailed due to trails still being snow-covered
-How heat tolerant are you? Last Fall I did Best of Italy in October and it was still in the 80's in Rome which is too hot for me. I did this tour starting the last week of August in 2014 and roasted in Rome but managed OK.
-Hiking will probably still be good in Switzerland.
Paris is good any time and deserves extra days at the end if you can manage it.
No matter when, you'd want a waterPROOF rain jacket with hood. You'll put it on and keep going, lol!! Here is a link to my old TR. This tour remains one of my favorites! Blockbuster sights every day!!